Recent Discoveries in Human Evolution: H. Sapiens 300,000 years old?

Welcome back to our discussion of recent exciting advances in our knowledge of human evolution:

  • Ancient hominins in the US?
  • Homo naledi
  • Homo flores
  • Humans evolved in Europe?
  • In two days, first H Sap was pushed back to 260,000 years,
  • then to 300,000 years!
  • Bell beaker paper

As we’ve been discussing for the past couple of weeks, the exact dividing line between “human” and “non-human” isn’t always hard and fast. The very first Homo species, such as Homo habilis, undoubtedly had more in common with its immediate Australopithecine ancestors than with today’s modern humans, 3 million years later, but that doesn’t mean these dividing lines are meaningless. Homo sapiens and Homo neandethalensis, while considered different species, interbred and produced fertile offspring (most non-Africans have 3-5% Neanderthal DNA as a result of these pairings;) by contrast, humans and chimps cannot produce fertile offspring, because humans and chimps have a different number of chromosomes. The genetic distance between the two groups is just too far.

Oldowan tool

The grouping of ancient individuals into Homo or not-Homo, Erectus or Habilis, Sapiens or not, is partly based on physical morphology–what they looked like, how they moved–and partly based on culture, such as the ability to make tools or control fire. While australopithecines made some stone tools (and chimps can make tools out of twigs to retrieve tasty termites from nests,) Homo habilis (“handy man”) was the first to master the art and produce large numbers of more sophisticated tools for different purposes, such as this Oldowan chopper.

But we also group species based on moral or political beliefs–scientists generally believe it would be immoral to say that different modern human groups belong to different species, and so the date when Homo ergaster transforms into Homo sapiens is dependent on the date when the most divergent human groups alive today split apart–no one wants to come up with a finding that will get trumpeted in media as “Scientists Prove Pygmies aren’t Human!” (Pygmies already have enough problems, what with their immediate neighbors actually thinking they aren’t human and using their organs for magic rituals.)

(Of course they would still be Human even if they part of an ancient lineage.)

But if an ecologically-minded space alien arrived on earth back in 1490 and was charged with documenting terrestrial species, it might easily decide–based on morphology, culture, and physical distribution–that there were several different Homo “species” which all deserve to be preserved.

But we are not space aliens, and we have the concerns of our own day.

So when a paper was published last year on archaic admixture in Pygmies and the Pygmy/Bushmen/everyone else split, West Hunter noted the authors used a fast–but discredited–estimate of mutation rate to avoid the claim that Pygmies split off 300,000 years ago, 100,000 years before the emergence of Homo sapiens:

There are a couple of recent papers on introgression from some quite divergent archaic population into Pygmies ( this also looks to be the case with Bushmen). Among other things, one of those papers discussed the time of the split between African farmers (Bantu) and Pygmies, as determined from whole-genome analysis and the mutation rate. They preferred to use the once-fashionable rate of 2.5 x 10-8 per-site per-generation (based on nothing), instead of the new pedigree-based estimate of about 1.2 x 10-8 (based on sequencing parents and child: new stuff in the kid is mutation). The old fast rate indicates that the split between Neanderthals and modern humans is much more recent than the age of early Neanderthal-looking skeletons, while the new slow rate fits the fossil record – so what’s to like about the fast rate? Thing is, using the slow rate, the split time between Pygmies and Bantu is ~300k years ago – long before any archaeological sign of behavioral modernity (however you define it) and well before the first known fossils of AMH (although that shouldn’t bother anyone, considering the raggedness of the fossil record).

This was a good catch. (Here is the relevant Dienekes article, plus Model-based analyses of whole-genome data reveal a complex evolutionary history involving archaic introgression in Central African Pygmies, and Whole-genome sequence analyses of Western Central African Pygmy hunter-gatherers reveal a complex demographic history and identify candidate genes under positive natural selection.) If the slow mutation rate matches the fossil record better than the fast, why use the fast–except if the fast gives you inconvenient results?

But now we have another finding, based on the Bushmen, which also pushes the Bushmen/everyone else split back further than 200,000 years–from BioRxiv, “Ancient genomes from southern Africa pushes modern human divergence beyond 260,000 years ago“:

Southern Africa is consistently placed as one of the potential regions for the evolution of Homo sapiens. To examine the region’s human prehistory prior to the arrival of migrants from East and West Africa or Eurasia in the last 1,700 years, we generated and analyzed genome sequence data from seven ancient individuals from KwaZulu-Natal, South Africa. Three Stone Age hunter-gatherers date to ~2,000 years ago, and we show that they were related to current-day southern San groups such as the Karretjie People. Four Iron Age farmers (300-500 years old) have genetic signatures similar to present day Bantu-speakers. The genome sequence (13x coverage) of a juvenile boy from Ballito Bay, who lived ~2,000 years ago, demonstrates that southern African Stone Age hunter-gatherers were not impacted by recent admixture; however, we estimate that all modern-day Khoekhoe and San groups have been influenced by 9-22% genetic admixture from East African/Eurasian pastoralist groups arriving >1,000 years ago, including the Ju|’hoansi San, previously thought to have very low levels of admixture. Using traditional and new approaches, we estimate the population divergence time between the Ballito Bay boy and other groups to beyond 260,000 years ago.

260,000 years! Looks like West Hunter was correct, and we should be looking at the earlier Pygmy divergence date, too.

Two days later, a paper from the opposite end of Africa appeared in Nature which–potentially–pushes H sapiens’s emergence to 300,000 years ago, “New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens“:

Fossil evidence points to an African origin of Homo sapiens from a group called either H. heidelbergensis or H. rhodesiensis. However, the exact place and time of emergence of H. sapiens remain obscure … In particular, it is unclear whether the present day ‘modern’ morphology rapidly emerged approximately 200 thousand years ago (ka) among earlier representatives of H. sapiens1 or evolved gradually over the last 400 thousand years2. Here we report newly discovered human fossils from Jebel Irhoud, Morocco, and interpret the affinities of the hominins from this site with other archaic and recent human groups. We identified a mosaic of features including facial, mandibular and dental morphology that aligns the Jebel Irhoud material with early or recent anatomically modern humans and more primitive neurocranial and endocranial morphology. In combination with an age of 315 ± 34 thousand years (as determined by thermoluminescence dating)3, this evidence makes Jebel Irhoud the oldest and richest African Middle Stone Age hominin site that documents early stages of the H. sapiens clade in which key features of modern morphology were established.

Comparison of the skulls of a Jebel Irhoud human (left) and a modern human (right) (NHM London)

Hublin–one of the study’s coauthors–notes that between 330,000 and 300,000 years ago, the Sahara was green and animals could range freely across it.

While the Moroccan fossils do look like modern H sapiens, they also still look a lot like pre-sapiens, and the matter is still up for debate. Paleoanthropologist Chris Stringer suggests that we should consider all of our ancestors after the Neanderthals split off to be Homo sapiens, which would make our species 500,000 years old. Others would undoubtedly prefer to use a more recent date, arguing that the physical and cultural differences between 500,000 year old humans and today’s people are too large to consider them one species.

According to the Atlantic:

[The Jebel Irhoud] people had very similar faces to today’s humans, albeit with slightly more prominent brows. But the backs of their heads were very different. Our skulls are rounded globes, but theirs were lower on the top and longer at the back. If you saw them face on, they could pass for a modern human. But they turned around, you’d be looking at a skull that’s closer to extinct hominids like Homo erectus. “Today, you wouldn’t be able to find anyone with a braincase that shape,” says Gunz.

Their brains, though already as large as ours, must also have been shaped differently. It seems that the size of the human brain had already been finalized 300,000 years ago, but its structure—and perhaps its abilities—were fine-tuned over the subsequent millennia of evolution.

No matter how we split it, these are exciting days in the field!

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Recent Exciting Developments in Human Evolutionary History: Naledi and Flores

A reconstruction of Homo naledi’s head by paleoartist John Gurche, who spent some 700 hours recreating the head from bone scans. Image credit: John Gurche / Mark Thiessen / National Geographic. source:

Continuing with our series on recent exciting discoveries in human genetics/paleo anthropology:

  • Ancient hominins in the US?
  • Homo naledi
  • Homo flores
  • Humans evolved in Europe?
  • In two days, first H Sap was pushed back to 260,000 years,
  • then to 300,000 years!
  • Bell beaker paper

One of the most interesting things about our human family tree (the Homo genus and our near primate relatives, chimps, gorillas, orangs, gibbons, etc.) is that for most of our existence, “we” weren’t the only humans in town. We probably coexisted, mated with, killed, were killed by, and at times perhaps completely ignored 7 other human species–Homo erectus, floresiensis, Neanderthals, Denisovans, heidelbergensis, rhodesiensis, and now Naledi.

That said, these “species” are a bit controversial. Some scientists like to declare practically every jawbone and skull fragment they find a new species (“splitters”,) and some claim that lots of different bones actually just represent natural variation within a species (“lumpers.”)

Take the canine family: dogs and wolves can interbreed, but I doubt great danes and chihuahuas can. For practical purposes, though, the behavior of great danes and chihuahuas is similar enough to each other–and different enough from wolves’–that we class them as one species and wolves as another. Additionally, when we take a look at the complete variety of dogs in existence, it is obvious that there is actually a genetic gradient in size between the largest and smallest breeds, with few sharp breaks (maybe the basenji.) If we had a complete fossil record, and could reliably reconstruct ancient hominin behaviors and cultural patterns, then we could say with far more confidence whether we are looking at something like dogs vs. wolves or great danes vs. chihuahuas. For now, though, paleoanthropology and genetics remain exciting fields with constant new discoveries!

Homo naledi and homo Floresiensis may ultimately be small branches on the human tree, but each provides us with a little more insight into the whole.

Naledi’s story is particularly entertaining. Back in 2013, some spelunkers crawled through a tiny opening in a South African cave and found a chamber full of bones–hominin bones.

Anthropologists often have to content themselves with a handful of bones, sometimes just a fragment of a cranium or part of a jaw. (The recent claim that humans evolved in Europe is based entirely on a jaw fragment plus a few teeth.) But in the Rising Star Cave system, they found an incredible 1,500+ bones or bone fragments, the remains of at least 15 people, and they haven’t even finished excavating.

According to Wikipedia:

The physical characteristics of H. naledi are described as having traits similar to the genus Australopithecus, mixed with traits more characteristic of the genus Homo, and traits not known in other hominin species. The skeletal anatomy displays plesiomorphic (“ancestral”) features found in the australopithecines and more apomorphic (“derived,” or traits arising separately from the ancestral state) features known from later hominins.[2]

Adult males are estimated to have stood around 150 cm (5 ft) tall and weighed around 45 kg (100 lb), while females would likely have been a little shorter and weighed a little less. An analysis of H. naledi‘s skeleton suggests it stood upright and was bipedal.[2][22][23] Its hip mechanics, the flared shape of the pelvis are similar to australopithecines, but its legs, feet and ankles are more similar to the genus Homo.[2][24]

I note that the modern humans in South Africa are also kind of short–According to Time, the Bushmen average about 5 feet tall, (that’s probably supposed to be Bushmen men, not the group average,) and the men of nearby Pygmy peoples of central Africa average 4’11” or less.

The hands of H. naledi appear to have been better suited for object manipulation than those of australopithecines.[2][25] Some of the bones resemble modern human bones, but other bones are more primitive than Australopithecus, an early ancestor of humans. The thumb, wrist, and palm bones are modern-like while the fingers are curved, more australopithecine, and useful for climbing.[3] The shoulders are configured largely like those of australopithecines. The vertebrae are most similar to Pleistocene members of the genus Homo, whereas the ribcage is wide distally as is A. afarensis.[2] The arm has an Australopithecus-similar shoulder and fingers and a Homo-similar wrist and palm.[24] The structure of the upper body seems to have been more primitive than that of other members of the genus Homo, even apelike.[3] In evolutionary biology, such a mixture of features is known as an anatomical mosaic.

Four skulls were discovered in the Dinaledi chamber, thought to be two females and two males, with a cranial volume of 560 cm3 (34 cu in) for the males and 465 cm3 (28.4 cu in) for females, about 40% to 45% the volume of modern human skulls; average Homo erectus skulls are 900 cm3 (55 cu in). A fifth, male skull found in the Lesedi chamber has a larger estimated cranial volume of 610 cm3 (37 cu in) [6]. The H. naledi skulls are closer in cranial volume to australopithecine skulls.[3] Nonetheless, the cranial structure is described as more similar to those found in the genus Homo than to australopithecines, particularly in its slender features, and the presence of temporal and occipitalbossing, and the fact that the skulls do not narrow in behind the eye-sockets.[2] The brains of the species were markedly smaller than modern Homo sapiens, measuring between 450 and 610 cm3 (27–37 cu in). The teeth and mandiblemusculature are much smaller than those of most australopithecines, which suggests a diet that did not require heavy mastication.[2] The teeth are small, similar to modern humans, but the third molar is larger than the other molars, similar to australopithecines.[24] The teeth have both primitive and derived dental development.[26]

The overall anatomical structure of the species has prompted the investigating scientists to classify the species within the genus Homo, rather than within the genus Australopithecus. The H. naledi skeletons indicate that the origins of the genus Homo were complex and may be polyphyletic (hybrid), and that the species may have evolved separately in different parts of Africa.[27][28]

Because caves don’t have regular sediment layers like riverbeds or floodplains, scientists initially had trouble dating the bones. Because of their relative “primitiveness,” that is, their similarity to our older, more ape-like ancestors, they initially thought Homo naledi must have lived a long time ago–around 2 million years ago. But when they finally got the bones dated, they found they were much younger–only around 335,000 and 236,000 years old,[1][4] which means H naledi and Homo sapiens–whose age was also recently adjusted–actually lived at the same time, though not necessarily in the same place.

(On the techniques used for dating the bones:

Francis Thackeray, of the University of the Witwatersrand, suggested that H. naledi lived 2 ± 0.5 million years ago, based on the skulls’ similarities to H. rudolfensis, H. erectus, and H. habilis, species that existed around 1.5, 2.5, and 1.8 million years ago, respectively.[35][36] Early estimates derived from statistical analysis of cranial traits yielded a range of 2 million years to 912,000 years before present.[2][37][38]

Dirks et al. (2017) obtained a much more recent age range of between 335,000 and 236,000 years ago from dating fossil teeth, sediments encasing the fossils and overlying flowstone. They used a variety of dating techniques, including radiocarbon dating of teeth, optically stimulated luminescence of sediment, palaeomagnetic analysis of flowstone, and most conclusively, uranium-thorium dating of cave flowstone and teeth and electron spin resonance dating of teeth.[1][4] The latter two types of measurements of teeth were performed on blind duplicate samples by two different labs.[1])

H naledi is unlikely to be a major branch on the human family tree–much too recent to be one of our ancestors–but it still offers important information on the development of “human” traits and how human and ape-like traits can exist side-by-side in the same individual (a theme we will return to later.) (Perhaps, just as we modern Homo sapiens contain traits derived from ancestors who mated with Neanderthals, Denisovans, and others, H naledi owes some of its traits to hybridization between two very different hominins.) It’s also important because it is one more data point in favor of the recent existence of a great many different human varieties, not just a single group.

Flores Hobbit aka Homo floresiensis source

The Flores hominin, (aka the Hobbit,) tells a similar tale, but much further afield from humanity’s evolutionary cradle.

The island of Flores is part of the Indonesian archipelago, a surprisingly rich source of early hominin fossils. Homo erectus, the famous Java Man, arrived in the area around 1.7 million years ago, but to date no erectus remains have been discovered on the actual island of Flores. During the last Glacial Maximum, ocean levels were lower and most of Indonesia was connected in a single continent, called Sundaland. During one of these glacial periods, H erectus could have easily walked from China to Java, but Flores remained an island, cut off from the mainland by several miles of open ocean.

Stone tools appeared on Flores about 1 million years ago, though we don’t know yet who made them, nor how they developed the technology necessary to make the journey.

The diminutive Hobbits show up later, around 50,000 to 100,000 years ago, though stone tools recovered alongside their remains have been dated from 50,000 to 190,000 years ago. Homo erectus is generally believed to have lived between 2 million and 140,000 years ago, and Homo sapiens arrived in Indonesia around 50,000 years ago. This places Floresiensis neatly between the two–it could have interacted with either species–perhaps descended from erectus and wiped out, in turn, by sapiens. (Or perhaps floresiensis represents an altogether novel line of hominins who left Africa on a completely separate trek from erectus.)

Unlike H naledi, whose diminutive stature is still within the current human range (especially of humans in the area,) floresiensis is exceptionally small for a hominin. According to Wikipedia:

The first set of remains to have been found, LB1, was chosen as the type specimen for the proposed species. LB1 is a fairly complete skeleton, including a nearly complete cranium (skull), determined to be that of a 30-year-old female. LB1 has been nicknamed the Little Lady of Flores or “Flo”.[2]

LB1’s height has been estimated at about 1.06 m (3 ft 6 in). The height of a second skeleton, LB8, has been estimated at 1.09 m (3 ft 7 in) based on measurements of its tibia.[3] These estimates are outside the range of normal modern human height and considerably shorter than the average adult height of even the smallest modern humans, such as the Mbenga and Mbuti (< 1.5 m (4 ft 11 in)),[32] Twa, Semang (1.37 m (4 ft 6 in) for adult women) of the Malay Peninsula,[33] or the Andamanese (1.37 m (4 ft 6 in) for adult women).[34]

By body mass, differences between modern pygmies and Homo floresiensis are even greater. LB1’s body mass has been estimated at 25 kg (55 lb). This is smaller than that of not only modern H. sapiens, but also H. erectus, which Brown and colleagues have suggested is the immediate ancestor of H. floresiensis. LB1 and LB8 are also somewhat smaller than the australopithecines from three million years ago, not previously thought to have expanded beyond Africa. Thus, LB1 and LB8 may be the shortest and smallest members of the extended human family discovered thus far.[citation needed]

Aside from smaller body size, the specimens seem otherwise to resemble H. erectus, a species known to have been living in Southeast Asia at times coincident with earlier finds purported to be of H. floresiensis.[3]

There’s a lot of debate about whether floresiensis is a real species–perhaps affected by insular dwarfism–or just a hominin that had some severe problems. Interestingly, we have a find from about 700,000 years ago on Flores of another hominin, which we think was also a Hobbit, but is even smaller than Flo and her relatives.

Floresiensis, like Naledi, didn’t contribute to modern humans. Rather, it is interesting because it shows the breadth of our genus. We tend to assume that, ever since we split off from the rest of the great apes, some 7 or 8 million years ago, our path has been ever upward, more complex and successful. But these Hobbits, most likely descendants of one of the most successful human species, (Homo erectus, who mastered fire, was the first to leave Africa, spread across Asia and Indonesia, and lasted for over a million and half years, far longer than our puny 300,000 years,) went in the opposite direction from its ancestors. It became much smaller than even the smallest living human groups. Its brain shrank:

In addition to a small body size, H. floresiensis had a remarkably small brain size. The brain of the holotype LB1 is estimated to have had a volume of 380 cm3 (23 cu in), placing it at the range of chimpanzees or the extinct australopithecines.[2][40] LB1’s brain size is half that of its presumed immediate ancestor, H. erectus (980 cm3 (60 cu in)).[40] The brain-to-body mass ratio of LB1 lies between that of H. erectus and the great apes.[41]

Nevertheless, it still made tools, probably controlled fire, and hunted cooperatively.

Whatever it was, it was like us–and very much not like us.

 

More on Naledi: Another Awesome Twig on our Human Family Tree and Homo Naledi was Chipping its Teeth Amazingly Often.

Can Ice Packs Stop A Seizure? (epilepsy)

Source: WHO infographics on epilepsy

Ice packs (cold packs) applied to the lower back at the first sign of a seizure may be able to halt or significantly decrease the severity of a seizure.

(If I’m correct, then this is the most important post on this blog, so please share.)

After researching ways to stop seizures, I suggested this to a friend with epilepsy. Her previous seizure lasted for 5 minutes (absolutely terrifying); this time her husband ran to the fridge, got two ice packs on her back, and the seizure immediately began slowing.

Obviously this is only an anecdote, but if you or a loved one has seizures, I can’t imagine it would hurt to try.

Let’s run through the evidence in favor of ice packs:

Seizures can definitely be triggered by being too hot–febrile seizures are somewhat common in children with fevers. Hyperthermia (heat stroke) can also cause seizures. And, yes, you can induce seizures in rats by heating them up. In the rat experiment, note that the seizure-prone rats’s temperatures went up more than the seizure-resistant rats–seizures may be more common in people whose bodies have difficulty regulating their temperatures.

Seizures also independently increase brain temperature in rats, and preventing this temperature increase, at least during hypoxic seizures, appears to protect rats against brain damage. But these are rats, obviously, not humans.

“Status epilepticus” is a seizure that lasts for more than 5 minutes or that recurs within a 5 minute period, and is considered a life-threatening emergency. 10-30% of people with status epilepticus die within 30 days. The immediate treatment for such cases is of course with anti-seizure medications, but some seizures (refractory status epilepticus) don’t even respond to this. In these cases, hypothermia–cooling the patient–appears to stop the seizures. (At least until the patient warms up again, but this gives doctors time to work out a better treatment plan.)

That said, seizure-prone people don’t need to be cold all the time–summer weather doesn’t cause an overall uptick in seizures (and some people’s seizures are actually triggered by being cold. If you are one of these people, ice packs may not be for you.)

I encountered the ice packs trick on forums where people were talking about treating seizures in dogs. (Yes, there are dogs with epilepsy.) There are many accounts of people successfully stopping or preventing their dogs from going into a seizure by grabbing a cold pack at the first warning signs and putting it directly onto the dog’s lower back:

We have a precious little Jack Russell Terrier named Scamp. … he is one of many dogs who have epilepsy. This has broken our hearts over the last three-and-a-half years. …

Recently my husband and I did research on the Internet regarding dogs with epilepsy. What we found was amazing. Something the eight or so vets we have seen over the past years had never even mentioned to us. It’s as simple as keeping a bag of ice in your freezer.

We had never tried this until this morning at 5:00 a.m. when Scamp began seizuring. I’ve never seen anything work so fast in my life. As I write this this morning I’m still amazed and can’t believe that what ended a seziure was as simple as a bag of ice and 2 teaspoons of vanilla ice cream to elevate his blood sugar level.

Here’s how it works: all you do is fill a food storage bag (at least one quart size) with crushed ice and leave it in the freezer. When your dog starts to seizure remove the bag of ice from the freezer and place it firmly on his lower back. Scamp came out of his seizure in about 30 to 60 seconds. …

He came out of the seizure smoothly and with no post-ictal symptoms whatsoever. He began to walk and followed my husband and I right into the kitchen. I went to the freezer and took out vanilla ice cream and took two teaspoons out of the carton. … he lapped it up. He was fine. He wanted to go outside so my husband followed him out to make sure he would be OK. He went to the bathroom, roamed around the yard for a bit and came in and went back to sleep on our bed. I’m still in shock.

The ice cream is to help get the dog’s blood sugar levels back up to normal. Humans might also find this useful.

Here’s another testimonial, from one of the links above:

We have been using ice packs to help manage our girl’s seizures for over a year now. From what I have heard first hand from others is that it either doesn’t work at all or it works fabulously. With our girl it “works fabulously”. It is not the miracle cure and it does not prevent future seizures but it definitely stops her grand mal right in its tracks. It is the most amazing thing I have ever seen. I would love to get it on video but as you all know a seizure is such a highly emotionally time that grabbing the camera is the last thing on my mind. If we get the ice pack on her within the first 15 seconds or so, the grand mal just suddenly stops. Like a light switch. All motor movement comes to a halt. She continues to be incoherent for a bit but all movements stop.

“Lani” is a 65 lb. Lab with a pretty thick coat. Our first attempts did not go so well because those little blue ice packs or baggies did nothing. So I custom made her packs using large seal a meal bags with water and rubbing alcohol that I keep in the freezer. It is perfect because its super cold but pliable so you can form it over their back. Every seizure she has is treated with the ice packs. She is also on high doses of meds, supplements, etc. but my personal belief is that the ice pack treatment helps to significantly reduce the length of the seizure.

The Journal of American Holistic Veterinary Medical Association published an article on the use of ice packs to stop seizures in dogs, A Simple, Effective Technique for Arresting Canine Epileptic Seizures, back in 2004. You can read it for a mere $95, or check out the highlights on Dawg Business’s blog:

Fifty-one epileptic canine patients were successfully treated during an epileptic seizure with a technique involving the application of ice on the back (T10 to L4). This technique was found to be effective in aborting or shortening the duration of the seizure.

And of course, in a study of rat seizures, the cold rats didn’t have any while the warm rats did.

The technique doesn’t work for all dogs, but it works for enough that it really seems like there must be something there.

But I haven’t read any cases of people using ice packs to treat seizures in humans–the (small quantity of) veterinary literature doesn’t appear to have made it over to human trials. But if it works for dogs, why not try it on people? It would be simplest, cheapest, least side-effect-inducing option for millions of people whose seizures can’t be fully controlled by medication.

Why does it work?

I don’t know. The ice packs probably aren’t in contact with the dogs for long enough to significantly lower the dog’s brain temperature, although they might lower the temperature of spinal nerves.

Perhaps the sudden cold just has an overwhelming effect on the brain that interrupts whatever feedback loop is causing the seizure.

From The Hidden Genetics of Epilepsy

Why not just medicate the seizures away?

Seizures are serious, potentially life-threatening conditions (actually, a friend of the family who had epilepsy died of a seizure that occurred while taking a bath.) Seizure medications, by necessity, are also serious and can have major side effects. According to the WHO, 70% of epileptics respond well to medication and live normal lives–leaving 30% of people who don’t. For many people, especially children, treatment is about trying to find a balance between minimizing harm from seizures and minimizing harm from anti-seizure medications.

So for anyone out there with epilepsy or another seizure condition, please consider ice packs as one more tool in your arsenal. And for any doctors out there, please do some research on this; there’s got to be some medical award for anyone who can prove it.

Good luck.

Is Racism an Instinct?

Everyone is a little bit racist–Hillary Clinton

If everyone in the world exhibits a particular behavior, chances are it’s innate. But I have been informed–by Harvard-educated people, no less–that humans do not have instincts. We are so smart, you see, that we don’t need instincts anymore.

This is nonsense, of course.

One amusing and well-documented human instinct is the nesting instinct, experienced by pregnant women shortly before going into labor. (As my father put it, “When shes starts rearranging the furniture, get the ready to head to the hospital.”) Having personally experienced this sudden, overwhelming urge to CLEAN ALL THE THINGS multiple times, I can testify that it is a real phenomenon.

Humans have other instincts–babies will not only pick up and try to eat pretty much anything they run across, to every parent’s consternation, but they will also crawl right up to puddles and attempt to drink out of them.

But we’re getting ahead of ourselves: What, exactly, is an instinct? According to Wikipedia:

Instinct or innate behavior is the inherent inclination of a living organism towards a particular complex behavior. The simplest example of an instinctive behavior is a fixed action pattern (FAP), in which a very short to medium length sequence of actions, without variation, are carried out in response to a clearly defined stimulus.

Any behavior is instinctive if it is performed without being based upon prior experience (that is, in the absence of learning), and is therefore an expression of innate biological factors. …

Instincts are inborn complex patterns of behavior that exist in most members of the species, and should be distinguished from reflexes, which are simple responses of an organism to a specific stimulus, such as the contraction of the pupil in response to bright light or the spasmodic movement of the lower leg when the knee is tapped.

The go-to example of an instinct is the gosling’s imprinting instinct. Typically, goslings imprint on their mothers, but a baby gosling doesn’t actually know what its mother is supposed to look like, and can accidentally imprint on other random objects, provided they are moving slowly around the nest around the time the gosling hatches.

Stray dog nursing kittens
Stray dog nursing kittens

Here we come to something I think may be useful for distinguishing an instinct from other behaviors: an instinct, once triggered, tends to keep going even if it has been accidentally or incorrectly triggered. Goslings look like they have an instinct to follow their mothers, but they actually have an instinct to imprint on the first large, slowly moving object near their nest when they hatch.

So if you find people strangely compelled to do something that makes no sense but which everyone else seems to think makes perfect sense, you may be dealing with an instinct. For example, women enjoy celebrity gossip because humans have an instinct to keep track of social ranks and dynamics within their own tribe; men enjoy watching other men play sports because it conveys the vicarious feeling of defeating a neighboring tribe at war.

So what about racism? Is it an instinct?

Strictly speaking–and I know I have to define racism, just a moment–I don’t see how we could have evolved such an instinct. Races exist because major human groups were geographically separated for thousands of years–prior to 1492, the average person never even met a person of another race in their entire life. So how could we evolve an instinct in response to something our ancestors never encountered?

Unfortunately, “racism” is a chimera, always changing whenever we attempt to pin it down, but the Urban Dictionary gives a reasonable definition:

An irrational bias towards members of a racial background. The bias can be positive (e.g. one race can prefer the company of its own race or even another) or it can be negative (e.g. one race can hate another). To qualify as racism, the bias must be irrational. That is, it cannot have a factual basis for preference.

Of course, instincts exist because they ensured our ancestors’ survival, so if racism is an instinct, it can’t exactly be “irrational.” We might call a gosling who follows a scientist instead of its mother “irrational,” but this is a misunderstanding of the gosling’s motivation. Since “racist” is a term of moral judgment, people are prone to defending their actions/beliefs towards others on the grounds that it can’t possibly be immoral to believe something that is actually true.

The claim that people are “racist” against members of other races implies, in converse, that they exhibit no similar behaviors toward members of their own race. But even the most perfunctory overview of history reveals people acting in extremely “racist” ways toward members of their own race. During the Anglo-Boer wars, the English committed genocide against the Dutch South Africans (Afrikaners.) During WWII, Germans allied with the the Japanese and slaughtered their neighbors, Poles and Jews. (Ashkenazim are genetically Caucasian and half Italian.) If Hitler were really racist, he’d have teamed up with Stalin and Einstein–his fellow whites–and dropped atomic bombs on Hiroshima. (And for their part, the Japanese would have allied with the Chinese against the Germans.)

picture-2Some quotes from the NewScientist article:

The murder victim, a West African chimpanzee called Foudouko, had been beaten with rocks and sticks, stomped on and then cannibalised by his own community. …

“When you reverse that and have almost two males per every female — that really intensifies the competition for reproduction. That seems to be a key factor here,” says Wilson.

Jill Pruetz at Iowa State University, who has been studying this group of chimpanzees in south-eastern Senegal since 2001, agrees. She suggests that human influence may have caused this skewed gender ratio that is likely to have been behind this attack. In Senegal, female chimpanzees are poached to provide infants for the pet trade. …

Early one morning, Pruetz and her team heard loud screams and hoots from the chimps’ nearby sleep nest. At dawn, they found Foudouko dead, bleeding profusely from a bite to his right foot. He also had a large gash in his back and a ripped anus. Later he was found to have cracked ribs. Pruetz says Foudouko probably died of internal injuries or bled out from his foot wound.

Foudouko also had wounds on his fingers. These were likely to have been caused by chimps clamping them in their teeth to stretch his arms out and hold him down during the attack, says Pruetz.

After his death, the gang continued to abuse Foudouko’s body, throwing rocks and poking it with sticks, breaking its limbs, biting it and eventually eating some of the flesh.

“It was striking. The female that cannibalised the body the most, she’s the mother of the top two high-ranking males. Her sons were the only ones that really didn’t attack the body aggressively,” Pruetz says …

Historically, the vast majority of wars and genocides were waged by one group of people against their neighbors–people they were likely to be closely related to in the grand scheme of things–not against distant peoples they’d never met. If you’re a chimp, the chimp most likely to steal your banana is the one standing right in front of you, not some strange chimp you’ve never met before who lives in another forest.

Indeed, in Jane Goodall’s account of the Gombe Chimpanzee War, the combatants were not members of two unrelated communities that had recently encountered each other, but members of a single community that had split in two. Chimps who had formerly lived peacefully together, groomed each other, shared bananas, etc., now bashed each other’s brains out and cannibalized their young. Poor Jane was traumatized.

I think there is an instinct to form in-groups and out-groups. People often have multiple defined in-groups (“I am a progressive, a Christian, a baker, and a Swede,”) but one of these identities generally trumps the others in importance. Ethnicity and gender are major groups most people seem to have, but I don’t see a lot of evidence suggesting that the grouping of “race” is uniquely special, globally, in people’s ideas of in- and out-.

For example, as I am writing today, people are concerned that Donald Trump is enacting racist policies toward Muslims, even though “Muslim” is not a race and most of the countries targeted by Trump’s travel/immigration ban are filled with fellow Caucasians, not Sub-Saharan Africans or Asians.

Race is a largely American obsession, because our nation (like the other North and South American nations,) has always had whites, blacks, and Asians (Native Americans). But many countries don’t have this arrangement. Certainly Ireland didn’t have an historical black community, nor Japan a white one. Irish identity was formed in contrast to English identity; Japanese in contrast to Chinese and Korean.

Only in the context where different races live in close proximity to each other does it seem that people develop strong racial identities; otherwise people don’t think much about race.

Napoleon Chagnon, a white man, has spent years living among the Yanomamo, one of the world’s most murderous tribes, folks who go and slaughter their neighbors and neighbors’ children all the time, and they still haven’t murdered him.

Why do people insist on claiming that Trump’s “Muslim ban” is racist when Muslims aren’t a race? Because Islam is an identity group that appears to function similarly to race, even though Muslims come in white, black, and Asian.

If you’ve read any of the comments on my old post about Turkic DNA, Turkey: Not very Turkic, you’ll have noted that Turks are quite passionate about their Turkic identity, even though “Turkic” clearly doesn’t correspond to any particular ethnic groups. (It’s even more mixed up than Jewish, and that’s a pretty mixed up one after thousands of years of inter-breeding with non-Jews.)

Group identities are fluid. When threatened, groups merged. When resources are abundant and times are good, groups split.

What about evidence that infants identify–stare longer at–faces of people of different races than their parents? This may be true, but all it really tells us is that babies are attuned to novelty. It certainly doesn’t tell us that babies are racist just because they find people interesting who look different from the people they’re used to.

What happens when people encounter others of a different race for the first time?

We have many accounts of “first contacts” between different races during the Age of Exploration. For example, when escaped English convict William Buckley wandered into an uncontacted Aborigine tribe, they assumed he was a ghost, adopted him, taught him to survive, and protected him for 30 years. By contrast, the last guy who landed on North Sentinel Island and tried to chat with the natives there got a spear to the chest and a shallow grave for his efforts. (But I am not certain the North Sentinelese haven’t encountered outsiders at some point.)

But what about the lunchroom seating habits of the wild American teenager?

If people have an instinct to form in-groups and out-groups, then races (or religions?) may represent the furthest bounds of this, at least until we encounter aliens. All else held equal, perhaps we are most inclined to like the people most like ourselves, and least inclined to like the people least like ourselves–racism would thus be the strongest manifestation of this broader instinct. But what about people who have a great dislike for one race, but seem just fine with another, eg, a white person who likes Asians but not blacks, or a black who like Asians but not whites? And can we say–per our definition above–that these preferences are irrational, or are they born of some lived experience of positive or negative interactions?

Again, we are only likely to have strong opinions about members of other races if we are in direct conflict or competition with them. Most of the time, people are in competition with their neighbors, not people on the other side of the world. I certainly don’t sit here thinking negative thoughts about Pygmies or Aborigines, even though we are very genetically distant from each other, and I doubt they spend their free time thinking negatively about me.

Just because flamingos prefer to flock with other flamingos doesn’t mean they dislike horses; for the most part, I think people are largely indifferent to folks outside their own lives.

Race: The social construction of biological reality, pt 3

Oh man! We are finally at part three! The part in which I attempt incorporating two-D space into our diagram:

race3

Right, so as we turn our car around and head back up the road, we notice an intriguing turnoff in the Congolese rainforest: a tribe of the shortest people in the world, the Pygmies. According to Wikipedia:

A pygmy is a member of an ethnic group whose average height is unusually short; anthropologists define pygmy as a member of any group where adult men are on average less than 150 cm (4 feet 11 inches) tall.[1] A member of a slightly taller group is termed “pygmoid“.[2]

The term is most associated with peoples of Central Africa, such as the Aka, Efé and Mbuti.[3] If the term pygmy is defined as a group’s men having an average height below 1.55 meters (5 feet 1 inch), then there are also pygmies in Australia, Thailand, Malaysia, the Andaman Islands,[4] Indonesia, the Philippines, Papua New Guinea, Bolivia, and Brazil,[5] including some Negritos of Southeast Asia.

Women of the Batwa Pygmies
Women of the Batwa Pygmies

Basically, whenever humans live in tropical rainforests, there’s a good chance they’ll get shorter. (Rainforests also produce pygmy elephants.) Maybe it’s because short people can move more easily through the dense forest, or an adaptation to low levels of iodine, sunlight, or other nutrients–I don’t really know.

Wikipedia estimates that there are between 250,000 and 600,000 pygmies living in the Congo rainforest:

Genetically, the pygmies are extremely divergent from all other human populations, suggesting they have an ancient indigenous lineage. Their uniparental markers represent the most ancient divergent ones right after those typically found in Khoisan peoples. African pygmy populations possess high levels of genetic diversity,[10] recent advances in genetics shed some light on the origins of the various pygmy groups. …

“We studied the branching history of Pygmy hunter–gatherers and agricultural populations from Africa and estimated separation times and gene flow between these populations. The model identified included the early divergence of the ancestors of Pygmy hunter–gatherers and farming populations ~60,000 years ago, followed by a split of the Pygmies’ ancestors into the Western and Eastern Pygmy groups ~20,000 years ago.”

But I recall–was it WestHunt?–objecting that the authors of this paper used a too-fast estimation of genetic mutation rates. Oh here it is:

There are a couple of recent papers on introgression from some quite divergent archaic population into Pygmies ( this also looks to be the case with Bushmen). Among other things, one of those papers discussed the time of the split between African farmers (Bantu) and Pygmies, as determined from whole-genome analysis and the mutation rate. They preferred to use the once-fashionable rate of 2.5 x 10-8 per-site per-generation (based on nothing), instead of the new pedigree-based estimate of about 1.2 x 10-8 (based on sequencing parents and child: new stuff in the kid is mutation). The old fast rate indicates that the split between Neanderthals and modern humans is much more recent than the age of early Neanderthal-looking skeletons, while the new slow rate fits the fossil record – so what’s to like about the fast rate? Thing is, using the slow rate, the split time between Pygmies and Bantu is ~300k years ago – long before any archaeological sign of behavioral modernity (however you define it) and well before the first known fossils of AMH (although that shouldn’t bother anyone, considering the raggedness of the fossil record).

See my review of Isaac Bacirongo and Nest's Still a Pygmy
See my review of Isaac Bacirongo and Michael Nest’s Still a Pygmy

Let’s split the difference and say that one way or another, Pygmies split off from their hunter-gatherer neighbors and became isolated in the rainforest quite a while ago.

Before we drive on, I’d like to pause and note that I’m not entirely comfortable with using the way Pygmies are sometimes used in racial discussions. Yes, they are short, but they otherwise look a lot like everyone else in the area. Pygmies go to school, often speak multiple languages, live in cities, work at real jobs, read books, operate businesses, drive cars, fall in love, get married, build houses, etc. For more on Pygmies see my review of Isaac Bacirongo’s memoir Still a Pygmy (Isaac is a Pygmy man who speaks, IIRC, 5 languagues, attended highschool, and owned/ran successful pharmacies in two different cities in the DRC before the army burned them down during a civil war.)

Now I admit that Isaac is just one guy and I don’t know what the rest of the Pygmies are like.

People over-thought ancestry long before 23 and Me
Different classes of Mexican mestizos: people over-thought ancestry long before 23 and Me

But let’s hop back in our car, for at the other end of this road we have not a small town of isolated forest-dwellers, but a large group we have so far neglected: the Native Americans.

The indigenous peoples of North and South America today number about 60 million people, plus some quantity of mixed-race people (mestizos.) In some areas these mestizos are majority European by ancestry; in others they are majority Indian; studies in Mexico, for example, estimate that 80-93% of the population is Mestizo, with Indian ancestry averaging between 31% and 66% in different regions. The people of El Salvador are about 86% mestizo; Chileans are about 40% Indian and 60% Europeans; Columbia is about 49% mestizo; etc.

Unfortunately, Wikipedia doesn’t list the total number of mestizos, and I don’t have time to calculate it, but I will note that the total population of both continents, including Canada and the USA, is about 1 billion people.

map of gene-flow in and out of Beringia, from 25,000 years ago to present
map of gene-flow in and out of Beringia, from 25,000 years ago to present

We’re not sure exactly when (or how) the Indians got here, but it looks like they arrived around 10-20,000 years ago across the then-Bering Landbridge. (I think we should also keep in mind the possibility that they could have built boats.) According to Wikipedia:

Scientific evidence links indigenous Americans to Asian peoples, specifically Siberian populations, such as the Ket, Selkup, Chukchi and Koryak peoples. Indigenous peoples of the Americas have been linked to North Asian populations by the distribution of blood types, and in genetic composition as reflected by molecular data, such as DNA.[192] There is general agreement among anthropologists that the source populations for the migration into the Americas originated from an area somewhere east of the Yenisei River. The common occurrence of the mtDNA Haplogroups A, B, C, and D among eastern Asian and Native American populations has long been recognized.[193] As a whole, the greatest frequency of the four Native American associated haplogroups occurs in the AltaiBaikal region of southern Siberia.[194] Some subclades of C and D closer to the Native American subclades occur among Mongolian, Amur, Japanese, Korean, and Ainu populations.[193][195]

Genetic studies of mitochondrial DNA (mtDNA) of Amerindians and some Siberian and Central Asian peoples also revealed that the gene pool of the Turkic-speaking peoples of Siberia such as Altaians, Khakas, Shors and Soyots, living between the Altai and Lake Baikal along the Sayan mountains, are genetically close to Amerindians.[citation needed] This view is shared by other researchers who argue that “the ancestors of the American Indians were the first to separate from the great Asian population in the Middle Paleolithic.”[196][197] 2012 research found evidence for a recent common ancestry between Native Americans and indigenous Altaians based on mitochondrial DNA and Y-Chromosome analysis.[198] The paternal lineages of Altaians mostly belong to the subclades of haplogroup P-M45 (xR1a 38-93%;[199][200][201] xQ1a 4-32%[199][200]).

Hilaria Supa, Indigenous Peruvian Congresswoman https://en.wikipedia.org/wiki/Hilaria_Supa
Hilaria Supa, Indigenous Peruvian Congresswoman

These ancient Siberians also had some “European” DNA, as do modern Siberians, but they are most closely related to their neighbors to the south, throughout the rest of Asia. Native American DNA is super fascinating, but we don’t have time to get into it all. On the grand scale, Native Americans are genetically Asians, separated from the rest of the clade by (probably) a mere 13-20,000 years. (Somewhat coincidentally, the Dire wolf, Smilodon, giant beaver, ground sloth, giant Columbian mammoth (Mammuthus columbi), woolly mammoth, mastodons, giant short-faced bear, American cheetah, scimitar cats (Homotherium), American camels, American horses, and American lions all went extinct in North America around 12,000 years ago.)

On the grand scale of human history, (200,000 years, more or less,) 13-20,000 years is not very long, and the Native Americans have not diverged too much, physically, from their cousins in Asia. The G-allele mutation of the EDAR gene arose about 30,000 years ago somewhere in east Asia and gives both modern Asians and Native Americans (but not Europeans and Africans) their characteristic hair and skin tone. While Native Americans are clearly physically, culturally, and geographically distinct from other Asians, (just as Europeans and south-Asian Indians are distinct from each other,) they are genetically close enough that they unquestionably clade together in the greater racial schema.

Also credit Robert Lindsay
Also credit Robert Lindsay

As I’ve said before, my diagram is just one way to represent one aspect of the genetic (and physical) distances between people.

Here is another diagram, not mine, which tells the same story in a different way (though it estimates a much lower genetic distance between Bushmen and Bantus than I’d expect. Oh well. different studies get different results; that’s why replication and meta-analysis are super important):

The Melanesians of Papua New Guinea and Australia are in pink (there are some mixed Melanesian / Polynesian populations in the world, but our road trip skipped them.) Their nearest relatives are other south Asians and Polynesians, but those same south Asians are themselves more closely related to Europeans than Australians. Diagrammed like this, it’d be understandable to break off south Asians into one race and put Caucasians, Native Americans, and East Asians into a single race. And I suppose you could, if you wanted to and could get everyone else to start using your categories. Race is biologically real and quite obvious at the macro scale, but a few small groups like Aborigines and Bushmen introduce existential uncertainty that intellectuals can quibble over.I don’t think it would be terribly useful rearrangement, though, for all of the reasons discussed over the past three posts in this series.

Well, that’s the end of our big road trip! I hope you’ve enjoyed it, and that it’s cleared up that nagging question people seem to have: How can Nigerians be more closely related to Europeans than some other Africans? Have a great day, and enjoy the drive home.

Haak et al’s full graph

WARNING: This post is full of speculations that I am recording for my own sake but are highly likely to be wrong!

Click for full size
From Haak et al.

Hey, did you know that this isn’t actually Haak et al’s full DNA graph? The actual full dataset looks like this:

 

Picture 1Picture 2

 

 

 

 

 

 

Isn’t it beautiful?

You’re going to have to click for the full size–sorry I couldn’t fit it all into one screen cap. I’m also sorry that the resolution is poor, and therefore you can’t read the labels (though you should be able to figure out which is which if you just compare with the smaller graphic at the top of the screen. (Supposedly there’s a higher resolution version of this out there, but I couldn’t find it.)

Why the reliance on a greatly cropped image? Just the obvious: the big one is unwieldy, and most of the data people are interested in is at the top.

But the data at the bottom is interesting, too.

On the lefthand side of the graph, we have a measure of granularity–how much fine detail we are getting with our genetic data. The bottom row, therefore, shows us the largest genetic splits between groups–presumably, the oldest splits.

From left to right, we have selections of different ethnic groups’ DNA. Old European skeletons constitute the first group; the mostly pink with some brown section is Native North/South American; the blue and green section is African; the big wide orange section is mostly European and Middle Eastern; then we have some kind of random groups like the Inuit (gold), Onge (pink, Indian Ocean), and Australian Aborigines; the heavily green areas are India; the mixed-up area splitting the green is Eurasian steppe; the yellow area is East Asian; and the final section is Siberian.

Level One: Sub-Saharan Africa (SSA) vs. Non-Sub-Saharan Africa

The bottom row shows us, presumably, the oldest split, between the orange and the blue. All of these light blue groups, from the Ju Hoan (Bushmen/San) to the Yoruba (Nigeria,) Somalis to Hadza (Tanzania,) African Americans to Shua (Khoe speakers of Namibia/Botswana,) are from Africa–sub-Saharan Africa, I’d wager (though I’m not sure whether Ethiopia and Somalia are considered “sub-Saharan.”)

All of the other groups–including the sampled north-African groups like Saharawari (from Western Sahara,) Tunisians, Algerians, Mozabites (Algeria,) and Egyptians–show up in orange.

(Note: Light green and orange are completely arbitrary color choices used to represent the DNA in these graphs; there is nothing inherently “orange” or “green” or any other color about DNA.)

I would not actually have predicted this–other studies I have read predicted that the split between the Bushmen, Pygmies, and other groups in Africa went back further in Africa than the split between Africans and non-Africans, but perhaps the Sahara has been the most significant barrier in human history.

Interestingly, the split is not absolute–there are Sub-Saharan groups with non-SSA admixture, and non-SSA groups with SSA admixture. In fact, most of the SSA groups sampled appear to have some non-SSA admixture, which probably has something to do with back-migration over the centuries; predictably, this is highest in places like Somalia and Ethiopia, fairly high along the east coast of Africa (which has historically been linked via monsoon trade routes to other, non-African countries;) and in African Americans (whose admixture is much more recent.) (Likewise, the admixture found in some of the hunter-gatherer peoples of southern Africa could be relatively recent.)

The Non-SSA groups with the most SSA admixture, are north African groups like the aforementioned Algerians and Tunisians; Middle Eastern groups like the Druze, Syrians, Bedouins, Jordanians, etc.; “Mediterranean” groups like the Sicilians and Maltese; various Jewish groups that live in these areas; and a tiny bit that shows up in the people of the Andaman Islands, Australia, and PNG.

(Oh, and in various old European skeletons.)

Level Two: “Western” vs. “Eastern”

Moving on to level two, we have the next big split, between “Easterners” (mostly Asians) and “Westerners” (mostly Europeans and Middle-Easterners.)

Natives of North/South America, Inuits, Andaman Islanders, Australian Aborigines, Papuans, the Kharia (an Indian tribe that has historically spoken a non-Indo-European language,) some central or northern Asian steppe peoples like the Evens (Siberians,) and of course everyone from the Kusunda (Nepal) through China and Japan and up through, well, more Siberians like the Yakuts, all show up as mostly yellow.

Everyone from Europe, the Middle East, the Caucuses, and all of the sampled Indian populations except the Kharia have orange.

A bunch of little groups from the middle of Eurasia show up as about half-and-half.

Interestingly, some of the older European hunter-gatherer skeletons have small quantities of “Eastern” DNA; this may not represent admixture so much as common ancestry. It also shows up, predictably, in Turkey and the Caucuses; in Russia/Finns; tiny quantities in places like the Ukraine; and quite significantly in India.

Significant “Western” admixture shows up in various Natives North/South Americans (probably due to recent admixture,) the Andaman Islands, Aborigines, PNG, (this may represent something to do with a common ancestor rather than admixture, per se,) and Siberia.

Level Three: Native North/South Americans vs. “Easterners”

At this point, the “light pink” shows up in all of the sampled indigenous tribes of North and South America. A fair amount of it also shows up in the Inuit, and a small quantity in various Siberian tribes. A tiny quantity also show up in some of the older European skeletons (I suspect this is due to older skeletons being more similar to the common ancestors before the splits than trans-Atlantic contact in the stone age, but it could also be due to a small Siberian component having made its way into Europe.)

Even at this level, there is a big difference evident between the groups from Central and South America (almost pure pink) and those from northern North America, (significant chunk of orange.) Some (or all) of that may be due to recent admixture due to adoption of and intermarrying with whites, but some could also be due to the ancestors of the Chipewyans etc. having started out with more, due to sharing ancestors from a more recent migration across the Bering Strait. I’m speculating, of course.

Level Four: Intra-African splits

I don’t know my African ethnic groups like I ought to, but basically we have the Bushmen (aka San,) and I think some Khoe / Khoi peoples in green, with a fair amount of green also showing up in the Pygmies and other hunter-gatherers like the Hadza, plus little bits showing up in groups like the Sandawe and South African Bantus.

Level Five: Australian Aborigines, PNG, and Andamanese split off.

Some of this DNA is shared with folks in India; a tiny bit shows up in central Asia and even east Asia.

Level Six: Red shows up.

This reddish DNA is found in all “Siberian” peoples, people who might have moved recently through Siberia, and people who might be related to or had contact with them. It’s found throughout East Asia, eg, Japan and China, but only found in high quantities among the Inuit and various Siberian groups. At this resolution, oddly, no one–except almost the Itelmen and Koryak–is pure reddish, but at higher resolutions the Nganasan are, while the Itelmen and Koryak aren’t.

Level Seven: The “Indos” of the Indo-Europeans show up

Although no pure light green people have yet been found, their DNA shows up everywhere the Indo-Europeans (aka Yamnaya) went, with their highest concentration in India. Perhaps the light green people got their start in India, and later a group of them merged with the dark blue people to become the Yamnaya, a group of whom then migrated back into India, leaving India with a particularly high % of light green DNA even before the dark blue shows up.

Interestingly, some of this light green also show up in the Andamanese.

Level Eight: The “Europeans” of the Indo-Europeans show up

The dark blue color originates, in the left-hand side of the graph, with a several-thousand years old population of European hunter-gatherers which, as you can see in the slightly younger populations on the far left, nearly got wiped out by a nearly pure orange population of farmers that migrated into Europe from the Middle East. This dark blue population managed to survive out on the Eurasian Steppe, which wasn’t so suited to farming, where it merged with the light-green people. They became the Yamnaya aka the Indo-Europeans. They then spread back into Europe, the Middle East, India, central Asia, and Siberia. (The dark blue in modern Native American populations is probably due to recent admixture.)

Level Nine: The Hadza

The Hadza (a hunter-gatherer people of Tanzania) now show up as bright pink. No one else has a lot of bright pink, but the Pygmies (Mbutu and Biaka,) as well as a variety of other eastern-African groups located near them, like the Luo, Masai, and the Somalis have small amounts.

Level Ten: The Onge (Andamanese)

Not much happens here, but the Onge (from the Andaman Islands) turn peach and stay that way. It looks like a small amount of peach DNA may also be found across part of India (southern India, I’m assuming.)

Level Eleven: Chipewyans (North America)

The Chipewyans turn brown; brown is also found in small quantities in Central America, in moderate quantities in eastern North America, and in the Eskimo/Inuit.

Level Twelve: Pygmies

The Biaka and Mbuti Pygmies differentiate from their neighbors. Tiny quantities of Pygmy DNA found in probably-nearby peoples.

Level Thirteen: Inuit/Eskimo

They become distinctly differentiated from other North American or Siberian tribes (olive green.), Their olive green shade is found in small quantities in some Siberian tribes, but interestingly, appears to be totally absent from other Native American tribes.

Level Fourteen: Horn of Africa

A dusty peach tone is used for groups in the Horn of Africa like the Somalis and Ethiopians, as well as nearby groups like the Dinka. Small amounts of dusty peach are are also found along the East Africa, North Africa, and the Middle East. Smaller amounts appear to be in a variety of other groups related to the Bushmen.

Level Fifteen: The light green turns teal

All of the light green in Europe turns teal, but much of the light green in India stays light green. (Teal also shows up in India.) I have no idea why, other than my aforementioned theory that India had more light green to start with.

Level Sixteen: Amazon Rainforest tribes

The Kuritiana and Suri show up in light olive; light olive is also found in small quantities in other parts of Central and South America, and tiny bits in parts of North America, and maybe tiny amounts in the Eskimo but I don’t see any in the Chukchi, Itelmen, etc.

Level Seventeen: Bedouins

The Bedouins turn light purple; this DNA is also found through out the Middle East, Turkey, North Africa, the Mediterranean (eg Sicily), Greece, Albania, Spain, Bulgaria, Ashkenazim, and a tiny bit In India.

Level Eighteen: Some Bushmen appear to split off from some other Bushmen.

I don’t know much about these groups.

Level Nineteen: Nothing interesting appears to happen.

Please remember that all of this is me speculating. I am definitely not an educated source on these matters, but I hope you’ve had as much fun as I’ve had peering at the DNA and thinking about how people might have moved around and mixed and split to make the colors.

 

Are the Pygmies Retarded?

While researching the previous post, I came across a claim that the Pygmies are retarded due to having IQs around 55.

No, the Pygmies are not retarded.

If you’ve already read Two Kinds of Dumb, you already know why, and don’t need to continue on. But if you’ve just wandered in, here’s the quick and dirty version:

An actual diagnosis of mental retardation requires not only a low IQ score (I think the bar is 75 but could be 70, I forget,) but also major life impairments. That is, the person must be unable to do, unsupervised, the normal things people do to function, like hold down a job, get dressed, or feed themselves.

While I don’t know the exact IQs of the pygmies, all of the evidence I’ve seen suggest that the average is probably pretty low. For starters, books are heavy, so hunter-gatherers tend not to carry them around, which has a real impact on the average hunter-gather’s ability to read. Second, hunter-gatherers tend not to conduct much trade, so they tend not to need much in the way of mathematics. Some groups don’t even have words for numbers over three. Such groups tend to score lousily on math tests.

I’ve searched high and low for whether or not Pygmy languages contain words for numbers over 3, and come up with nada. But I think Pymies tend to use a lot of words from other languages/be multi-lingual, so if the Pygmies are speaking some other language they picked up from an agricultural tribe, the language could easily have a full suite of number words whether the Pygmies had any interest in numbers or not.

Third, given neither books nor maths in Pygmy history, it’s unlikely that there’s been any selective pressure on the Pygmies to adapt to readin’ and ‘rithmetic.

Fourth, there is a pretty strong correlation between IQ scores and technological complexity. You don’t have to think of IQ as “intelligence” if you don’t want to, but whatever it is, it is necessary for building technologically complex societies. If the hunter-gatherer lifestyle is your thing, then you don’t need much in the way of IQ.

And fifth, their heads are kind of small. Unfortunately, brains have to go somewhere, and this poses a limit on grey matter.

That said, Pygmies are perfectly functional in their environment. They can hunt and gather their own food, carry on some trade with their neighbors, build their own houses, make their own clothes, get dressed, cook, take care of their children (one Wikipedia article claims that one Pygmy group has some of the highest level of fatherly involvement in child-rearing in the world,) are bi- and tri-lingual, and otherwise conduct their lives.

If you and I got dropped in the rainforest, we’d probably die within three or four days.

To over-simplify, mental retardation is generally caused by some form of traumatic brain injury, say, by getting dropped on your head as a child, eating lead, or being born with an extra chromosome. These injuries change your IQ from what it should have been, and cause a general loss of brain functioning.

If you live in a society where the average IQ is 100, then the average person you meet with a 50 IQ is most likely someone who suffered a traumatic injury.

However, if you live in a society where the average IQ is 50, this is the normal, um-injured IQ of people in your society. It just means that people in your society are bad at reading and math, not that they were all dropped on their heads as infants and cannot care for themselves.

“But wait,” I hear you saying, “what if Pygmy low IQ is caused by malnutrition? After all, they ARE pretty short.”

Doubtful. There’s no reason to think that Pygmies would have been more malnourished than all of their neighbors for thousands of years (we have records going back that far.) Also, their height is genetic (see studies on Pygmy genetics,) not due to malnutrition. According to Westhunter, an average-heighted person would have to starve to death twice before mere malnourishment would make them as short as a pygmy.

 

Are Pygmies human?

I’ve also come across this question during my research, so I think it bears addressing.

Look, the term “human” is a social construct. So is the whole concept of “species.” You can come up with a personal definition of “human,” if you feel like it, that doesn’t include the Pygmies. Certainly their neighbors, who rape, murder, eat, and enslave the Pygmies (and sometimes evict them to make more room for gorillas,) do not regard the Pygmies as human. Personally, I look down on the Pygmies’ neighbors for their despicable behavior toward the Pygmies, rather than look down on the Pygmies for their stature and lifestyle.

Practically speaking, people only declare other groups of people “not humans” in order to justify killing them. I have no desire to kill the Pygmies; it seems more pleasant to me to live in a world where Pygmies exist, while still recognizing them as one of the most genetically distinct groups on Earth.

 

Animal Morality

I know it shouldn’t surprise me when people post outright, bold-faced lies about, say, the nature of humanity, but somehow I still stare in shock for a split second or two before struggling with whether or not to respond.

It’s generally a bad idea to respond, another thing you would think I’d have learned by now. No one likes the guy who starts every comment with, “Actually…”

Today’s lie was, to paraphrase slightly due to memory being imperfect, “Animals are so loving and compassionate, even to members not of their own species! Humans totally fail at compassion. We should learn from our ape cousins and ancestors!” The sentiments were accompanied by an adorable picture of an orangutan holding a baby tiger.

Okay, the exclamation points are my own additions.

First, the obvious: This shit is a baldfaced lie. If animals were regularly compassionate and loving to members of other species, lions would be vegans and running adoption agencies for baby gazelles whose parents had fallen victim to unfortunate accidents. If animals were regularly loving and compassionate, we wouldn’t make a big deal out of it every time a hippo and turtle hang out together. Does someone write a picture book documenting every set of human kids who become friends? Or every human who feeds a pet? Of course not. We only document these animal stories because they’re unusual.

Reality is boring. Lies entertain.

“But wait,” I hear you saying, “My dog totally loves me.”

Your dog is the result of thousands of years of selective breeding specifically for friendliness to humans. Also, you give it food. Does your dog give you food?

No.

Anyway, how nice are animals?

“Altruism” is defined (by the Wikipedia, anyway,) as, “behaviour by an individual that increases the fitness of another individual while decreasing the fitness of the actor.” Wikipedia defines “compassion” as a, “response to the suffering of others that motivates a desire to help.”

I’m not going to even try to define “love.”

Now, the definition of altruism itself hints that inter-species altruism probably isn’t a thing you’re going to see very often, because if the altruist increases the genes of another species at the expense of their own genes, then whatever genes originally drove the altruist to be altruistic become less common. Over time, the inter-species altruist gets replaced by everyone else, and altruism disappears.

This doesn’t mean that no one can ever be altruistic–altruism works just fine if it’s directed at your near kin. Animals that have a strong instinct to care for their family members and a certain level of intelligence can even apply that caring instinct to non-family. But I wouldn’t expect much friendliness from a crocodile.

It does means that claims about widespread altruism among animals toward other animals that aren’t family are probably nonsense.

The vast majority of observed instances of animal altruism involve close kin, pack members, or behavior that would normally be directed toward one’s kin but happened, by accident, to involve a non-related individual. The Wikipedia list on the subject, while incomplete and imperfect, gives a good impression.

In reality, the vast, vast majority of animals in this world do not give a shit about members not of their own species. Most of them don’t even care about members of their own species who aren’t family, and some will even eat their own children.

What about claim two, that humans suck at compassion?

Certainly some of us do. Humans aren’t as nice as I wish we were. Compassion, trust, kindness, etc., are all traits I would like to see more of in humans. But compared to animals, we look like Mother Theresa. How many animals set out little houses, baths, and seed-filled feeders for other animals? How many animals buy cancer treatments for their pets? For that matter, how many animals feed and care for a pet, period?

These behaviors are almost exclusively human.

Humans adopt orphans, run into burning buildings to rescue each other, fund social welfare nets, and spend a lot of time trying to prove to each other just how much they care about each other. Movies and novels basically wouldn’t exist without our capacity to empathize with strangers.

Humans support this level of altruism because our societies have bred us, like dogs, for it. (And since different societies are different, that means that different societies have bred different types/levels of altruism and compassion.) It is only in modern, first-world societies that we see anything resembling wide-spread altruism. Slavery–generally outlawed throughout the West in the late 17 or 1800s–is still common throughout many parts of Africa and the rest of the third world. If you really want to break your heart, just go read about Cambodian children sold as sex slaves at the age of 5. (Clearly the solution is more orangutans.)

(Seriously, what is the point of having a military if we don’t occasionally swoop into those brothels, behead everyone running the place, and then leave their heads on pikes about the city as warnings to everyone else?)

How about the final claim: Should we learn from the other apes?

Which do you think is friendlier, your dog or a wolf? The dog, obviously.

Human society has been getting steadily less violent for about as long as we’ve managed to account. Everyday life in non-state and pre-state societies is/was about as violent as Russia during WWII, only a bit more spread out. Chimpanzees, like wolves, are well-known for their violence. They wage war, form alliances to overthrow their leaders, and murder chimpanzee babies in order to breed faster with their mothers.

But what about bonobos?

I’ll grant that they have a lot of sex. They’re also known to be less aggressive than chimpanzees. This is not the same as being less aggressive than H sapiens. Until I see some data on bonobo homicide, I’m going to continue suspecting that bonobos are more violent than humans. Remember, some human societies–25 of them, though several of those are teeny–have gotten their murder rates down below 1 in 100,000 people. Since 50,000 is the high end estimate of number of bonobos on earth, if even one bonobo kills another bonobo once every two years, they’d still have 6x the homicide rate of Japan.

Not to mention that, unsurprisingly, empathy and “emotional intelligence” appear to correlate rather well with regular intelligence–and since humans are noticeably smarter (on average) than chimps, gorillas, bonobos, or tigers, this implies that we are probably better at empathizing with others, feeling compassion, and being generally altruistic.

This is pretty obvious to just about anyone who has ever had to deal with a bully, or looked at the average IQs of criminals.

 

All of which leads us back to our initial quandary: Why do people tell (and believe) such obvious lies?

I posit two reasons:

1. The other is but a foil for the self, and most people don’t really process words into their exact meanings, but into internal feeling-states. So when they say, “Animals are so caring and compassionate; we should be more like them,” they actually mean, “I like being caring and compassionate; you should be more like me.”

2. People who are caring and compassionate tend also to be caring and compassionate about animals, so thinking nice things about animals because it makes them happy.

Most of the time, people seem to remember that crime rates are actually lower among humans than among wild animals, and so don’t get too close to bears. (Sometimes they forget, but Gnon has his way with them.) But I do occasionally encounter people who really, truly seem to believe this. They really think that humans are irredeemably evil, and the world would be better off without us. But a world without humans would be a world with even less empathy and compassion than our current world, not more.

 

Neanderthals!

So I still haven’t tracked down anything I consider a good source on the percent of Neanderthal DNA in people from particular regions of Europe, and I should note that at this point, I consider pretty much *everything* in the field of Neanderthal DNA in modern homo Sapiens quite speculative and not nearly has solid as people make it ought to be. But it’s still really interesting stuff, so here goes. I’ll start with a little background information in case you haven’t been following along:

1. Modern people tend to have a little bit of archaic DNA from non-human hominins. Pretty much everyone outside of Africa (including African Americans and even some Africans) has Neanderthal DNA; folks down in Papua New Guinea also have Denisovan DNA (I can’t remember if people outside of PNG have Denisovan.) People in Africa, I hear, have their own admixture from whoever else was living down in Africa. Oh, and people in Tibet have admixture from the hominins who used to live in Tibet before them.

2. Interestingly, the Neanderthal DNA does not appear to be concentrated where you’d think it would be. Sure, Neanderthals themselves hung out primarily in Europe and the Middle East, but American Indians seem to have the most Neanderthal DNA, followed by East Asians. (I consider these findings especially speculative.)

I have noticed in studying maps of different waves of human migrations that where one wave follows another, the first wave ends up way out in the fringes. Take, for example, the parts of Europe where people speak Celtic languages. Celtic languages were once widespread in Europe, covering France, Spain, Britain, Ireland, Switzerland, and a few other places, like possibly a town in Turkey. Today, Celtic languages are spoken in isolated pockets on the outer costs of Ireland, Scotland, and Wales. There are a few other isolated spots on the mainland coast where the languages persisted until fairly recently. Germanic peoples invaded all of these countries, taking them over and imposing their languages, until the Celtic languages are only left at the fringes, in places protected by their isolation.

So, likewise, perhaps Europe itself, being closer to Africa, had more invasions and so ended up with less Neanderthal DNA than the Americas, which were really bloody hard to invade.

There are a lot of other ways one group could get more Neanderthal DNA than another.

3. So how Neanderthal are you? On average, I believe non-African people have about 2.5% Neanderthal DNA.

For perspective, you have 32 great-great-great grandparents, who were probably born around 150 years ago, and 64 great-great-great-great grandparents, whom we’ll just neatly say were born around 170 years ago.

1/32 = 3.1%, so you’d expect to receive about 3.1% of your DNA from each of your 3xGreat Grandparents. 1/64 = 1.6%, so you get about 1.6% from each of your 4X Great Grandparents. So that’s where the average person’s Neanderthal contribution is–it’s like having one Neanderthal ancestor from the mid 1800s.

A lot of people claim to be ethnically Irish based on less.

4. I suspect Europe’s Neanderthal hotspot is Sardinia.

Speculations later.