Freddie deBoer attacks “Blank Slateism”, posing questions for those who deny the importance of genetic variation in human behavioral variation

July 24, 2022 • 12:30 pm

After I read the piece below by Freddie deBoer on his Substack site, a piece that’s a critique of Blank-Slateism and of those who deny that variation in genes influences variation in behavior, I decided to look him up. I found three relevant bits of information in his Wikipedia biography, quoted directly below (Wikipedia spells his name DeBoer, with a capital “D,” though the man himself writes “deBoer”).

  • DeBoer identifies himself as a “Marxist of an old-school variety”.
  • DeBoer’s first book, The Cult of Smart, was published in 2020 by All Points Books.  Gideon Lewis-Kraus, writing for The New Yorker, says the book “argues that the education-reform movement has been trammelled by its willful ignorance of genetic variation.” Lewis-Kraus groups deBoer with “hereditarian left” authors such as Kathryn Paige Harden and Eric Turkheimer in their shared emphasis on the importance of recognizing the heritability of intelligence when formulating social policy.

In DeBoer’s case, though, he seems to think that the genetic basis of variation in intelligence can help inform social and educational policy, while, as I noted in my review of Harden’s book in the WaPo, although she recognizes that intelligence (her construal of it is “educational attainment”) is highly heritable, with a lot of inter-individual variation based on genes, she insists that knowing that genetic basis (or a kid’s genetic “endowment”) should play no role in educational policy—or at least she doesn’t suggest one.  By the way, the Wikipedia article mentions some strong criticism of deBoer’s book.

And the third bit of information:

  • DeBoer has been a teacher at both the high school and college level.

I don’t care much about his politics when he writes about behavior genetics; I can assess what he says without knowing he was an “old-school Marxist”. That may help condition his views that people try to downplay the importance of genes, though I’d think that a Marxist would emphasize . I haven’t read his book, so I can’t comment there, but I was interested that he’s taught on several levels, so has some experience when he claims that it’s very, very difficult to change student achievement by changing educational methods.

It’s a short article; click below to read it:

Now there are hardly any people who believe in an entirely blank slate, and all of us think that traits like intelligence are ultimately the products of genes interacting with environments. So yes, there’s a genetic contribution to nearly all human traits. The question taken up by deBoer, however, is about the variation in a trait among individuals—how much of that variation is produced by variation in the genes among individuals as opposed to environmental varitaion (or various sorts of interactions). As I’ve said before, the proportion of observed variation in a trait among individuals in a population due to variation in their genes is called heritability. It ranges, of course, from 0% to 100%, or, expressed as a fraction, from 0 to 1.0.  (I’m leaving out technical details here, for by “genetic variation” I mean “additive genetic variation”—the genetic effects that can be selected on either naturally or artificially. The higher the heritability, the greater the effect of genetic variation on trait variation.

At any rate, as Harden says in her book, the heritability of many human traits is quite high. This has been shown in a variety of ways: adoption studies, twin studies (raised together and apart), and “genome-wide association studies” (GWAS)—Harden’s own method.

If I were asked to give a figure for the heritability of IQ or academic achievement, I’d say “about 50%”. What that means is that about half of the variation that we see among individuals within a population is due to variation among individuals’ genes in that population, the rest being due to environmental variation, non-heritable genetic variation, and interaction variance.  Many other human traits have high heritability, as do many traits in other animal species. In fact, among thousands of artificial selection experiments in plants and animals, I know of only three that failed to produce a response, and only when heritability is zero do you fail to get a response. (Two of those happened to be my experiments, selecting on directional asymmetry in flies.) Darwin was right when he said in On the Origin of Species, “Breeders habitually speak of an animal’s organization as something quite plastic, which they can model almost as they please.” That attests to the ubiquity of variation in populations of captive animals, and that variation is undoubtedly greater in larger wild populations.

The upshot is that we expect nearly all human traits to show heritability within populations, with some of the values being quite high. Remember, though, that heritability is a figure that applies only to individuals in a specified population who on average experience the same variation of environments. You can’t extrapolate the heritability within a population to different populations, who may live in different environments or have different genes. Thus, although there’s substantial variation in Caucasians (as Harden shows) for academic achievement, you cannot say that the difference in academic achievement between American Caucasians and minorities in America is also based on genetic differences between groups. Why? Because there are environmental differences among groups that affect academic achievement. Genetically extrapolating from within groups to between groups is arrant error that has fueled a lot of racism.

But as far as I see, deBoer is simply addressing the blank-slate position that “not much of the variation we see in populations for intelligence (or anything else) has anything to do with genetic variation.”  This Blank-Slateism is characteristic of the “progressive” Left, who adhere to the extreme malleability of human behavior, and also explains why so many on the Left are also opposed to the claims of evolutionary psychology. It’s the same mindset that denies the importance of genes on behavior today that also denies the importance of genes affecting modern human behavior having been installed in our genome by natural selection. To see this viewpoint, have a look at A Blog That Shall Not Be Named, but one that you all know.

After that bit of boring instruction, on to deBoer, who wants Blank-Slaters to answer nine questions.  Before he poses them, he argues that the modern tendency of people to be snarky and  jokey, and the tendency to be divisive and willfully ignorant on social media, has kept people from really seeing the merit in a view that a lot of human behavioral variation is due to variation in their genes. I’ll quote:

But the urge to joke – driven, no doubt, by getting more “engagement” for doing so than by actually being constructive – has driven out substance from almost every online space I can imagine. It’s a nightmare, like a shitty open mic night you can’t escape.

Critics of behavioral genetics, the academic subfield devoted to the exploration of how genes influence cognition and behavior, are a good example. Although I believe it’s overwhelmingly likely such influence exists, that position is perfectly subject to criticism, and since historically people have gone very wrong in interpreting that relationship good criticism is important. But online, even very well-informed critics of behavioral genetics spend almost all of their time ridiculing and loling rather than arguing. This problem is particularly acute in this domain because so many want to dismiss any consideration of how genes influence how human beings act by saying that anyone who asks elementary questions in that regard is a Nazi.

Indeed. The reason that this kind of work is denigrated is simply because people working on human behavioral genetics are all thought to have a racist or sexist agenda, or even favor eugenics. But the genetics of human behavior is a fascinating field, if for no other reason that it tells us that a lot of variation in things like alcoholism, school achievement, smoking, risk-taking, and so on, are based on variation in genes. What are those genes? How do they influence our behavior? Many of these questions can be answered without being a Nazi!

deBoer has a specific practical reason to be interested:

This is all particularly frustrating for me because my concern with genes and cognition has always been very practical. My first book lays out the case that the assumption that all students are perfectly equal in potential, integrated into educational ideology in large part by John Dewey, has profound negative consequences for our education system – and hurts no one more than students who struggle in school. I have already detailed how blank-slate thinking brought us No Child Left Behind, the most disastrous educational policy in the history of our country. The entire charter school ideology, which empowers plutocrats to defund public schools and attack teachers and their unions, depends entirely on the idea that students all have exactly equal inherent ability and that any suggestion otherwise is a way to dodge accountability. This discussion is not theoretical; it has teeth, and our public schools are in the crosshairs. It’s beyond frustrating that asking elementary questions about genetics and behavior is greeted with jokes and not with arguments.

As I said, I haven’t read deBoer’s book and so can’t speak about how blank-slateism led to the No Child Left Behind policy. But it’s up to deBoer, as it was up to Harden, to tell us exactly how the genetic variation for achievement which clearly occurs within populations can be used to improve education for everyone. The paragraph above implies that you can’t use genetic information to improve education (Harden’s position), but can use it to avoid educational programs that assume everyone can achieve the same heights given the right environments. But are there such programs? How would genetic knowledge lead us to change the educational system? Maybe deBoer tells us in his first book, but he doesn’t tell us here. (He does say that knowing that there are different genetic potentials for achievement would have forestalled the “No Child Left Behind” program. Assessing that claim is also above my pay grade).

Anyway, here are a few questions deBoer would like Blank-Slaters to answer. At first I thought he was confusing variation among individuals within a population (the right question) with variation among populations (the wrong question), but he wasn’t. I’ll give and comment on seven of his nine questions. And yes, I agree with deBoer that many people, especially on the Progressive Left, try to ignore most of these questions:

  • The nervous system and brain are produced by the same basic process of genetic transmission from parents to child as any other part of the body. We’re developing greater knowledge over time of how genetic variants influence the development of brain structures. How could it be possible that differences in the genome would result in no differences at all in the functioning of the brain and greater nervous system, which produce our cognition and behavior? Wouldn’t this amount to some sort of Cartesian dualism where the mind and the body are entirely separate, the kind of thinking that was left behind hundreds of years ago?

Note here that he’s talking about genetic variation (“differences in the genome”), though he should have emphasized “within a population”.

  • Do you believe that animal cognition and behavior are influenced by the individual animal’s genome? Does a given dog’s particular genome influence its cognition and behavior? If not, how is it that some dogs can be selectively bred to be more or less aggressive, more or less friendly? If genes can influence the cognition and behavior of animals how could it be that genes don’t influence the cognition and behavior of humans, who are after all just another species of animal?

This is a good question. Although we have culture, it’s hard to believe that we’re so exceptional among animals that most of our behavioral and cognitive traits have a heritability of near zero. (Remember, you can artificially select animals to have all sorts of different behaviors. And natural selection has done that in the wild. Note that his statement “genes can influence the cognition and behavior of humans” is a bit misleading. Of course it does, but the question is one of genetic variation among individuals, not the development of cognition within an individual.

Two more questions:

  • Even ardent environmentalists will generally concede that some people are predisposed toward athletic success or are born beautiful. What is fundamentally different between a genetic predisposition towards athletic talent or physical attractiveness and a genetic predisposition to being good at math or bad at chess?
  • Often, fraternal siblings have significantly different performance on academic and cognitive metrics, even if born less than a year apart and despite sharing the same parents, home, family environment, family income, access to resources, and privileges. How does a purely environmentalist perspective account for this difference? How is it that children who are very closely matched on a great many environmental and familial variables often differ profoundly in various attributes of academic ability and personality

Below is the one question I think is ill-posed. An environmentalist perspective could account for child prodigies, for an “accident” of development might confer neuronal wiring that could lead to such prodigies. “Idiot savants” (Dustin Hoffman in “Rain Man” portrays one) could be the result of some quirk of development that affects the brain in a way that makes one both autistic but also extremely accomplished in one area. But it doesn’t even have to make you autistic. A developmental anomaly can just be a neuronal developmental accident having nothing to do with a specific mutation. In fact, deBoer inadvertently supports an environmentalist perspective here by noting an absence of prodigies among the siblings of prodigies:

  • How does a purely environmentalist perspective account for child prodigies like Terry Tao, who was doing differential equations at 8 years old, or Awonder Liang, who defeated a grandmaster in chess at 9 years old? Are their parents just that much better than the average parent? If so, why do prodigies almost never have fraternal siblings who are also prodigies? Did the parents forget how to raise children to be geniuses? Why has no one been able to replicate the parenting that produces prodigies and geniuses?

The next two are good questions, and if you answer them honestly you’ll be admitting that a substantial proportion of variation in human achievement, behavior, and personality rest on variation in genes (go look up estimates of heritabiltiies for human traits):

  • Are long-observed familial tendencies in schizophreniabipolar disorder, and other psychiatric conditions real? If yes, then that would mean that we can identify some genetic influences on behavior and cognition. Similarly, there are proposed genetic influences for developmental and cognitive disorders that impact behavior and thinking.
  • What it means that identical twins resemble each other in cognitive and personality outcomes whether raised together or apart, or that adoptive children resemble their adoptive siblings in such outcomes no more than they do a random person, is a matter of serious and sustained controversy. But that those dynamics exist is not a matter of controversy; a tremendous amount of data demonstrates that these tendencies exist summatively, whatever their origins. What are purely environmentalist explanations for this tendency? Why are adoptive siblings so often profoundly dissimilar to each other and similar to their genetic siblings despite being raised in very different environments?

His points are good ones, and will make Blank-Slaters squirm.

Finally deBoer brings up the lack of efficacy in improving schooling as evidence for genetic variation that isn’t malleable to environmental changes, like improved methods of education:

  • How is it that massive changes in environment and schooling have been found, over and over again, to prompt no changes in academic outcomes? What is the purely environmentalist explanation for this?

Well, you could say that there are cultural differences between children of different groups that haven’t been properly addressed by education (John McWhorter, for instance, thinks that teaching kids reading by phonics could help efface the gap in achievement between whites and blacks). Or there may be educational methods that we haven’t thought of yet. deBoer may well be right that there are inherent (i.e., genetic) differences in potential for achievement between individuals that prevent any educational reform from creating more equal and higher outcomes. But I’m not convinced from this last assertion that the explanation is genetic. This question differs from the rest in that there is no genetic data to support it save the difficulty of educational reform.

Let me emphasize that I’m largely in agreement with deBoer. Blank-Slateism is dominating the scientific views of the Extreme Left, and it’s had an inimical effect on research, rendering some scientific questions taboo not only to being researched, but even discussed. What deBoer needs to tell us is what he recommends we should do about the inefficacy of schooling. Perhaps his view is “nothing: we can’t change unequal outcomes.”


Was Ernst Mayr a eugenicist?

July 13, 2022 • 1:30 pm

A while back the Society of Systematic Biologists (SSB) had second thoughts about the name of its Ernst Mayr Award, a prize given to the best student paper presented at the SSB’s annual meeting. (Mayr, one of my scientific heroes, also endowed that award and left a sum in his will to keep funding it.) If you look at the rationale for the proposed de-naming of the award, given at the link above, you’ll find there were two reasons proposed by the SSB Council for this:

Many current members do not see themselves reflected in awards that bear the names of these early scientists and can feel excluded as potential recipients as a result. In a field whose composition still does not reflect global human diversity, having an award named after a particular individual reinforces that members with other identities are outsiders.

In other words, Mayr was an old white man and its name could make people feel unsafe. I have strong doubts about whether this is true, although perhaps a tiny handful of individuals could object on those grounds, but they would surely be outweighed by the proud recipients of the “Ernst Mayr Award”, who could put it on their c.v.s. Many of these would be people of color.. The other reason was this:

This proposal is not intended to cast judgement on the legacy of Ernst Mayr, who was a prolific and profound scholar of evolutionary biology and a dedicated champion of students, nor are we intending to defend the contents of his writings which some find problematic.

Yes, Mayr was one of the greats, a man who in fact helped found and fund the SSB. And the proposal doesn’t even mention which writings people found “problematic”. I wasn’t aware of any, and I read a lot of Mayr, but of course I didn’t know about his correspondence or other personal issues. I know that he wrote a lot of antiracist stuff, some of which you’ll see here and some of which you can see at this link.

At any rate, thanks to the intercession of Ceiling Cat, the SSB membership narrowly voted down the deplatforming of Mayr.  It was a squeaker, though, as most of the SSB voted to remove the name. Fortunately, it takes a 2/3 vote to do so. From the SSB’s announcement:

After much deliberation, the Council approved sending the constitutional amendment to the membership for their vote. Under our constitution, all amendments require approval by two-thirds of the voting members. While 63.4% of the voting members favored the change, this is short of the 66.7% required for the amendment to be adopted. Thus, the award will continue to be called the “Ernst Mayr Award in Systematic Biology”.

That was a victory for rationality, especially because the reasons for the renaming were either unclear or unspecified, and I suspect that most of the “rename” votes were by people who didn’t know much about Mayr.

Since I wrote my posts on this, one reader informed me that a letter existed from Mayr to his friend Francis Crick, a letter in which Mayr apparently espoused some pro-eugenic views. This letter, written in 1971, can be found in the NIH collection here, and a better version, a pdf, is here.

And indeed, Mayr does show himself in favor of what he calls “positive eugenics”, but eugenics based not on race but on rewarded breeding for “positive traits”, or, alternatively, as one correspondent interpreted it, on eliminating genetic defects that could be somehow rectified. But it is absolutely clear in Mayr’s views, and in this paper he wrote, is that his views had absolutely nothing to do with race (Mayr was an anti-racist), and that he thought in terms of incentives for individuals possessing more “desired” traits to have more children. He absolutely abjured the racist views of Shockley and others. Here’s are excerpts from his 1971 letter to Crick, but I urge you to read it for yourself

I have been favoring positive eugenics as far back as I can remember. As I get older, I find the objective as important as ever, but I appreciate also increasingly how difficult it is to achieve this goal, particularly in a democratic western society. Even if we could solve all the biological problems, and they are formidable, there still remains the problem of coping☂with the demand for “freedom of reproduction,” a freedom which fortunately will have to be abolished anyhow if we are not drown in human bodies. The time will come, and perhaps sooner than we think, when parents will have to take out a license to produce a child. No one seems to question that it requires a license for such a harmless activity as driving a car, and yet such an important activity as influencing the gene pool of the next generation can be carried out unlicensed. A biologist will understand the logic of this argument, but how many non-biologists would? Obviously, then, we need massive education. Such education is going to be – paralyzed at the very start if it gets mixed up with racist and anti-racist arguments. This is why the Academy has to disassociate itself from Shockley’s arguments. JI have heard him argue by the hour, and it is very obvious that he treats human beings like so many sodium atoms or pi mesons. Population differences for him are real, the differences between individuals, however, are errors of sampling that can be ignored by focusing on mean values. I will not claim that Shockley does not somewhere know that his approach is wrong, because he must realize that even differences between individuals have a significant genetic basis. What is crucial, however, is that he seems to ignore these individual differences in his conclusions and generalizations.

Now as to positive action! The most important thing at this time/to stop talking about “The White” and “The Black.” As long as we use this language, we will produce only heat but no light. We must think in terms of adopting a strategy that will permit meaningful research without offending people’s sensitivities and without coming too aggressively in conflict with popular prejudices. Please do not forget that thinking in anthropology in this country was shaped by Boas (and his various disciples) and in psychology by the behaviorist school. Both schools magnify the importance of the environment and hardly mention or even deny the role of inheritance. The American school of psychoanalysis, likewise, denied any importance of inheritance, even in such clearly genetic conditions as schizophrenia. This must be kept in mind when one is thinking about strategies to be adopted for the initiation of meaningful eugenic research. A bull-in-the-china-shop attitude, like that of Shockley, will result only in the erection of impassable roadblocks. What is equally deplorable is the action of certain geneticists who imply, by overemphasizing the environmental uncertainties, that the genetic factors can be ignored as far as human abilities are concerned. But this is not the place to discuss this any further.

The question, then, is what Mayr meant by “positive eugenics”.  Did he want to encourage breeding of individuals to, say, raise the IQ of human populations, or was he trying to encourage people to breed who were free of genetic defects like schizophrenia? (We do some of the latter already, by either choosing embryos free from specific genetic diseases or telling parents early in pregnancy and allowing them to abort the fetus.)

I’ve had answers from colleagues on both sides. For example, one colleague interpreted Mayr as holding the former view: breeding of the best classes. I quote:

Yes this is par for the course for mid-century intellectuals. Very tiresome. Crick’s eugenics was undigested Galton.: very English and Edwardian, and based on class. Crick, for instance, supported Shockley’s right to spout his garbage along with many others. From the 1970s onwards, Crick learned to keep his opinions to himself. And don’t forget that Linus Pauling himself wanted people to be tattooed with their genetic defects so people would avoid having sex with them!
The key point is that [Mayr’s thinking] reveals how bad these people were about thinking through things they had learned as kids. Both just repeated garbage from the 1920s, which was very disappointing.
Another colleague plumped for the second alternative:

One problem is that the words “positive eugenics” have changed in meaning over time. People now associate those words with encouraging “genetically advantaged” people to have children. What Mayr meant by “positive eugenics” would now be called “gene therapy”: using molecular techniques to cure genetic diseases. He also considered other future technologies (in his time)  like in vitro fertilization to be a type of “positive eugenics”. Those are the two examples that he gave in discussing the future and potential uses and dangers of “positive eugenics.”

Even in this letter, Mayr is very careful to note the dangers associated with racism, and is very clearly an anti-racist.
It is not fair to damn Mayr for using a word in a reasonable, but different, way than people now use it. Now no one would use the word “eugenics” to talk about the things that Mayr was discussing, like gene therapy and in vitro fertilization. In vitro fertilization is now widely used and accepted. Gene therapy is more controversial and still in development, but there are lots of people who would happily use it to cure their genetic disease if they could.
The question, then, is whether Mayr really is using the words “positive eugenics” to mean “gene therapy” rather than “selective breeding of the best and the brightest.” If you read this paper from 1967, you see the antiracism, but also a sense that Mayr thinks that the human species could be improved by specified differential reproduction. But he’s also very pessimistic, saying that we know very little about the genetics of human traits and that nothing could be done for many generations.

Well, now that we have whole-genome sequencing and the construction of Genome Wide Association Studies (GWAS), we could indeed begin to do incentivized selection by rewarding people with traits that society wants to change: we just give bonuses to people with, say, high career achievement if they have more children. That would work given the estimates of heritability for such traits given by people like Kathryn Harden.

Would it work? Almost certainly, for most human traits have substantial heritability with a measured populations (Harden’s statistics come from whites), and if there is heritability, then there will nearly always be a response to selection.

Should we do this? HELL NO!  Getting the government or biologists involved in trying to make humanity move in a certain direction by choosing which traits are “best”, and then rewarding people that have those traits for producing more kids seems deeply unethical.  Who decides? Wouldn’t people object? And of course it would have to be implemented on a worldwide scale if you wanted to change our species. Besides, we are doing fine as we are and, I think, are not being dragged down by “bad genes”. Cultural changes are far better and faster at improving humanity, and far less invidious, than effecting genetic change. Plus this kind of incentivized breeding is extra odious because it would increase inequality among people.

But relevant to this topic, did Mayr espouse the “selective breeding” form of eugenics? I think you can say that he did in places, though you cannot say that he supported a bigoted form of eugenics that labeled ethnic groups as inferior, or wanted to impede people’s reproduction. And at any rate he never did anything about it.  To say that “eugenics” = “Nazi” is simply a boorish, tendentious, and unnuanced way to address a historical controversy, one that continues today with discussions about gene therapy and selective abortion.

So yes, you can find at least this letter as “slightly problematic”. Is that enough to remove Mayr’s name from an award? Not in my view, not unless you want to remove Crick’s and Pauling’s names from awards, and basically deplatform every biologist who was working before, say, 1950. Is anyone’s closet free from skeletons?

Indeed, it’s hard to think of any biologist of earlier generations who didn’t have views that many of us, including me, reject in our day. But given Mayr’s immense positive contributions, both to biology and to antiracism, I don’t see one letter, or even several and a paper, as sufficient to efface his name from an award. I’ve always thought that a name should be kept if it’s there to honor the positive achievements of a person, and also if that person’s existence was a plus for humanity. Surely Mayr qualifies on both counts.

Here’s Ernst in New Guinea as a young white biologist, before he became an old white biologist:

Wonderful fossil dinosaur embryo shows birdlike “tucked” posture before hatching

December 24, 2021 • 11:00 am

This is one the most stunning fossils I’ve seen in a long time. It’s an almost perfectly preserved dinosaur embryo that somehow died in the egg during the Late Cretaceous (100 mya-66mya). It’s not just amazing for its preservation, but also for the posture of the unhatched embryo, which resembles the posture that modern bird embryos (an also early birds themselves) assume soon before hatching. The inference is that the behaviors that precede hatching in birds, and help them through the tough process of getting out of the egg, actually evolved from their reptilian ancestors—the theropod dinosaurs, of which this specimen is one.

The paper appears in iScience and is free; click on the screenshot below or get the pdf here.

I’ve really conveyed the gist of the paper in the first paragraph above, but you need to see this embryo! Click to enlarge; all the photos are high-resolution

(from paper): Figure 1. Oviraptorid embryo inside an elongatoolithid egg (YLSNHM01266) Abbreviations: cev, cervical vertebra; cv, caudal vertebra; dv, dorsal vertebra; f, femur; fi, fibula; II-1, pedal phalanx II-1; il, ilium; is, ischium; m, mandible; mt-I, metatarsal I; mt-III, metatarsal III; mx, maxilla; p, pubis; pm, premaxilla; r, radius; s, scapula; t, tibia; ul, ulna. Scale is 1 cm.


The specimen is given the number YLSNHM01266, and is described as a “new non-avian theropod dinosaur embryo. . . from the Late Cretaceous Hekou Formation of southern China.” No species name is given because without a fossil of an adult in the vicinity, we have no idea. We can tell, however, that it is a theropod dinosaur, and an “oviraptorid oviraptorosaur“.

Oviraptors constitute is a group of theropod dinosaurs of varying sizes, which lived in what is now North America and Asia. Fossils show that they had feathers, parrot-like beak mandibles, sometimes bony crests on the head, and walked on their hind legs. Paleontological analysis combined with phylogeny shows, as Wikipedia notes, that they are “close to the ancestry of birds.” (The ancestor of birds is thought by most but not all paleontologists to be theropod dinosaurs.)

Here’s a group of diverse ovoraptors from Wikipedia. You can see that their skeletons are more birdlike than those of other dinosaurs. Some scientists, indeed, group them with birds! Four species have been found with feather impressions, so it’s likely that the group (including the baby above) had feathers, but couldn’t fly. Maybe one of the species below is the adult that would have developed from the juvenile above!

Back to the fossil.  Here’s part of a later figure that helps you make sense of what’s what in the photos above. The air cell, also present in modern bird eggs, is to the right between the embryo and the shell.

If you want the technical description of the posture, here it is from the paper. I’ve bolded the important parts.

The articulated embryonic skeleton is preserved curled inside its egg (YLSNHM01266), with the skull positioned ventral to the body (Figure 1). The egg is elongate ovoid in shape with dimensions of 16.7 cm long by 7.6 cm wide, and has characteristics typical of the egg family Elongatoolithidae (see STAR Methods for eggshell analysis). The skeleton is almost complete, without much apparent postmortem disruption. The anterior surface of the skull faces toward the pointed pole and is situated about egg mid-length at the level of the ilium in-between the flexed hindlimbs, with a pes [foot] on either side. The anterior cervical vertebrae are in line with the long axis of the skull. The presacral vertebral column is strongly bent in an angular manner, so that the upper back of the embryo faces the blunt pole of the egg (similar flexion of the vertebral column is found in modern in ovo skeletons, e.g. Balanoff and Rowe, 2007: Figure 4, Day 18, and is not likely to be a taphonomic artifact). The skeleton is ∼23.5 cm in total length, measured from the anterior tip of the skull to the last preserved caudal vertebra, and occupies nearly the entire width of the egg and most of the length, with the exception of a ∼1.9 cm space between the dorsal vertebrae and the blunt pole of the egg. This space may represent the air cell, a space usually found between the back of the embryo and the blunt pole of bird eggs (e.g., Rahn et al., 1979). However, this inference is tentative and awaits further evidence. The posterodorsal, sacral and caudal vertebrae almost form a straight line along the long axis of the egg. Although the precise developmental stage of the embryo is unclear, it is likely to represent a late-stage embryo because the skeleton is well ossified and is large in size relative to the space inside the egg, as inferred in MPC 100/971 (Norell et al., 2001).

Note that the specimen is 23.5 cm, or a bit more than nine inches long: as long as a dollar bill and half of another one (American dollar bills are almost exactly 6 inches long, and can be used for emergency measurements).

When modern birds hatch, they assume this position as the first of three stages prior to hatching: “pre-tucking”, “tucking” and “posttucking” (we know this clearly because, sadly, many pre-hatched birds have been dissected from the egg). I won’t go through the complicated description of the changes in posture, but here’s how it happens in a chicken, with the fetal dinosaur placed between “pretucking” and “tucking”. “Membrane penetration” is when the bird uses its bill to get out of the membrane in which the embryo is enclosed, and “pipping” is when it begins to peck through the shell (often a long process).

Apparently birds always tuck their heads below their right wing, not their left, before pipping. How they know left from right (genetically) is beyond me; but somehow this asymmetry is coded in the DNA:

And here are three examples of embryonic oviraptors compared to a modern bird (chicken) at the assumed similar stages:

(from paper): Figure 3. In-ovo late-stage embryos of non-avian and avian dinosaurs (A) Oviraptorid specimens (MPC 100/971, YLSNHM01266 & IVPP V20183), which potentially correspond to various tucking stages. (B) Domestic fowl Gallus ontogenetic series (day 16-20) (modified from Rowe (2003)). Not to scale. Silhouettes modified from PhyloPic.

Now the authors are very careful not to overinterpret a single fossil, but I do think it’s likely that the oviraptor fossils show that their pre-hatching positions and behavior was passed on to birds, as oviraptors are phylogenetically close to the ancestor of birds (though we don’t know whether the ancestor of birds was an oviraptor).

The only question remaining is: do all dinosaur embryos—not just those closely related to the ancestor of modern birds—show similar embryonic behavior? The answer is, as usual, we just don’t know. There’s a severe shortage of well-preserved dinosaur embryos, as you might imagine One specimen of a sauropod, a distant relative, seems to show a different fetal posture than the ones above.

I hope we can find more fossil embryos, because, although behavior doesn’t fossilize, the correlates of behavior—represented by the posture of embryos—do. In that sense the way modern birds hatch might what some systematists call a synapomorphy: a character shared by two species (or groups) because it was present in an ancestor—in this case the common ancestor of the ovoraptors and modern birds. And it’s surely an adaptive synapomorphy, because birds that can’t get out of the shell don’t leave any genes behind.


Xing, L. et al. 2021.  An exquisitely preserved in-ovo theropod dinosaur embryo sheds light on avian-like prehatching posturesiScience, in press.

Determinism doesn’t mean that you can’t change your behavior, or help others to

January 6, 2019 • 10:45 am

I’m a free-will “incompatibilist”: someone who sees the existence of physical determinism as dispelling the idea of contracausal, you-could-have-done-otherwise “free will”, which is the notion of free will most common among people. Many people find my view disturbing and fatalistic, and I’m often posed this question: “If everything is determined by the laws of physics mediated through our neurobiology, what’s the point of trying to change somebody’s mind?”

My response is that no, we can’t choose (via contracausal free will) whether we want to change someone’s mind, nor can they freely choose (in the same sense) whether to change it. But human brains are wired by both evolution and experience in a way that alters people’s behaviors when (in general) they would benefit from those changes. So, for example, if you learn that treating people in a certain way makes them treat you better back, your brain circuits for “better treatment” might be activated, and you might begin treating folks better.  And if you see someone treating others badly, your circuits to give them that advice might be activated. You might then advise them, and their own brain circuits may “take” that advice.

None of this is incompatible with determinism. People learn, often in a way that helps them get along better with others, perform better on the job or other aspects of life, and so on. The possibility of such changes might have been produced by evolution since such malleability might correlate with your status and well-being, which in turn might have been connected with your reproductive success. Or, on the cultural side, we avoid pain and seek pleasure, and our brains are capable of taking in advice or experience that would increase our well being and decrease ill being.

Likewise, advice from someone else can act as an environmental stimulus that activates brain circuits that alter behavior. Again, we have no free choice about whether to render advice to others, but that doesn’t mean that the advice can’t effect changes.

Pacific Standard has an interview with Stanford biologist and writer Robert Sapolsky, the author of the acclaimed book Behave: The Biology of Humans at Our Best and Worst. (Click on screenshot below for the interview.) Sapolsky discusses a lot of things about tribalism, but I’ll reproduce two exchanges about free will. (Sapolsky’s writing have shown him to be, like me, an incompatibilist who thinks that the notion of “you-can-do-otherwise” free will is an illusion.)

Here he expresses the difficulty in explaining to others why determinism doesn’t entail fatalism. Perhaps his answer is better or clearer than mine, and here it is:

TJ [Tom Jacobs]: You write that you don’t really believe in free will, but we nevertheless have an obligation to try to understand our behavior and make things better. Isn’t that something of a contradiction?

RS [Sapolsky]: I’m realizing how incredibly hard it is to articulate how an absence of free will is compatible with change.

Gaining new knowledge, having new experiences, being inspired by someone’s example—these are biological phenomena. They leave biological traces.

There are all sorts of neuro-pathways that analyze the world in terms of cause and effect. The knowledge that one person—or a bunch of high school students—really can make a difference can be inspiring. That means certain pathways have been facilitated, and, as a result of that, certain behaviors become more likely. Pathways to efficacy can also be weakened if you find out you have no control in a certain domain. Learning to be helpless is also biological.

TJ: So the fact free will is largely illusory does not mean the way we react to the world is static and unchanging.

RS: Absolutely not. There’s a vast difference between a biologically determined universe and fatalism.

h/t: Tom

Reader’s wildlife videos

October 9, 2016 • 7:30 am

Tara Tanaka has struck video gold again with this heartwarming video of seven wood ducks (Aix sponsa) being set free. (Tara’s Vimeo site is here and her flickr site is here.)

Seven little ducklings were lovingly raised by the dedicated staff of St. Francis Wildlife in Tallahassee, FL during the summer of 2016. I picked them up at St. Francis on the day of this video, and at first they were just going to send six of them home with me and keep the 7th one – a female – since something had just happened to her flight feathers and they were afraid that she would be an easy target for a predator. We decided that she’d be better off with her peeps than alone in her flight cage at St. Francis, so we caught her and packed her up for her final time in a crate. When I got them home I took the big tub to the water’s edge, and very gently rolled it on it’s side so that when I opened the hinged lid that they would hopefully file out together, and not explode out, flying in every direction, which I unfortunately learned in a previous release. Everything went as planned and they slowly swam out in wide-eyed wonderment in their new home. The first 25s or so was videoed right after they were released, and the last clip was shot later that afternoon as they met the eight three-month old Black-bellied Whistling Duck juveniles who are the terror of the swamp. Ironically, the little raggedy hen who almost didn’t get to taste freedom was the one who chased off the Whistling duck, and flapped at the end. They’ve been here a month now and all seven are doing fine. “Raggedy’s” feathers are growing back, and her short flights are getting longer each day. She and a somewhat raggedy drake have really bonded (you can see them together at :42), and I’m so glad they are all together.

This video was shot in 4K with a Panasonic GH4 + Nikon 300mm f2.8 ED IF ais lens using manual focus.

For best results, go over to the Vimeo site and put it on full screen and 4K high definition.

In which Science goes on trial and is exonerated all in one morning

July 6, 2015 • 6:30 am

by Grania

As Dara O’Briain once noted, of course Science doesn’t know everything. If science knew everything, it would stop and probably go and eat ice cream for the rest of its days. But sometimes we all wish that science had the answer to our particular question du jour. Then again, sometimes just because we don’t know the answer doesn’t mean that science hasn’t already figured it out for us. (Magnets, how do they work?)

This morning on Twitter, writer and journalist Tom Chivers asked this question.

This response came moments later.

(He went on to apologise graciously.)

So what does science have to say on why we think we got a phone-call when we didn’t? The BBC says here:

When your phone is in your pocket, the world is in one of two possible states: the phone is either ringing or not. You also have two possible states of mind: the judgment that the phone is ringing, or the judgment that it isn’t. Obviously you’d like to match these states in the correct way. True vibrations should go with “it’s ringing”, and no vibrations should go with “it’s not ringing”. Signal detection theory calls these faithful matches a “hit” and a “correct rejection”, respectively.

But there are two other possible combinations: you could mismatch true vibrations with “it’s not ringing” (a “miss”); or mismatch the absence of vibrations with “it’s ringing” (a “false alarm”). This second kind of mismatch is what’s going on when you imagine a phantom phone vibration.

For situations where easy judgments can be made, such as deciding if someone says your name in a quiet room, you will probably make perfect matches every time. But when judgments are more difficult – if you have to decide whether someone says your name in a noisy room, or have to evaluate something you’re not skilled at – mismatches will occasionally happen. And these mistakes will be either misses or false alarms.

It’s apparently similar to the system smoke detectors use. A false alarm is much less costly and less dangerous than a missed positive.

So there you go, Science is safe for another day. And perhaps you will forgive your neighbours next time their alarm goes off for no reason at all at 3am.




The things rats dream about

June 30, 2015 • 10:15 am

by Grania Spingies

We are such stuff
As dreams are made on, and our little life
Is rounded with a sleep.

The Tempest (4.1.168-170)

I should preface this with my regular caveat: I-am-not-a-scientist, nor do I play one on TV. My level expertise only allows me to say the rough equivalent of “Oh hey, this looks interesting.”

As a child I often used to watch my dogs dreaming. Clearly they were running, sometimes barking and huffing, sometimes panting. It used to fascinate me, and I wondered where in their heads they were running. Was it a field they knew? Were they alone or with companions? Were they chasing prey? Running for the fun of it? What does prey even look like to Canis lupus familiaris who may never met anything particularly prey-like in their modern suburban existence?

Once one of them barked so loud in her dream that she startled herself and woke up with a jump. I’d never seen a Labrador look more sheep-like when her eyes met mine. Unfortunately there was no way to ask her what she had been seeing in her dreams.

But it seems that remarkably a team of scientists has had a glimpse at what rats dream about.

Not an actual lab rat

Kiona Smith-Strickland over at Discover Magazine writes about a new study where a team looked at rats and determined remarkably that they dreamed about going places they were aware of but had not yet explored. She explains the process:

First, researchers let rats explore a T-shaped track. The rats could run along the center of the T, but the arms were blocked by clear barriers. While the rats watched, researchers put food at the end of one arm. The rats could see the food and the route to it, but they couldn’t get there.

Then, when the rats were curled up in their cages afterwards, scientists measured their neuron firing. Their brain activity seemed to show them imagining a route through a place they hadn’t explored before. To confirm this, researchers then put the rats back into the maze, but this time without the barriers. As they explored the arm where they had previously seen the food, the rats’ place cells fired in the same pattern as they had during sleep.

Neuroscientist Hugo Spiers, who co-authored the study, notes:

People have talked in the past about these kind of replay and pre-play events as possibly being the substrates of dreams, but you can’t ask rats what they’re thinking or dreaming. There is that really interesting sense that we’re getting at the stuff of dreams, the stuff that goes on when you’re sleeping.

You can read the paper here:

Hippocampal place cells construct reward related sequences through unexplored space by H Freyja Ólafsdóttir, Caswell Barry, Aman B Saleem, Demis Hassabis, Hugo J Spiers

Stunning duets in a neotropical wren

November 14, 2011 • 5:58 am

There’s a new paper in Science, brought to my attention by Ritchie S. King in the New York Times, that describes an amazing behavior in plain-tailed wrens (Pheugopedius euophrys). The species is neotropical: found in tropical forests in the mountains of Peru, Ecuador, and Colombia.  Here’s a photo from Wikipedia:

What’s amazing about this species is that the duet sounds like a single song, but actually consists of males and females alternating “syllables” at a rate of up to six per second.   When the female’s song has a tiny gap, the male fills in.  You can hear all this in the video below, and I’ll embed some songs from the paper.  The function of these songs is unknown, but they are probably involved in joint defense of territories.

The researchers, Eric Fortune et al., spent several months in the bamboo forests of Ecuador, recording wild and captive birds.  They also did playback experiments using “artificial song”.  The main results are described very well in this three-minute Science video below, presented by Fortune.  You’ll hear the duets as well as the single songs of one sex, showing the gaps that are filled in by the partner.

The authors found that the partners don’t just sing a stereotyped song, but adjust their songs to fill in whatever gaps are provided by the partner.  In other words, they’re sensitive to audio feedback from their mate, and, as the authors note, “are not relying on fixed-action patterns in the brain to generate duet song.”  As Fortune notes above, the female seems to play the “lead” in these songs, much like a partner who leads during a waltz.

Now I’m not sure if you can see this for free, but I’ll put the links to two movies of caged, duetting wrens. Below each movie is a sonogram that shows which partner is contributing which syllable.

Movie 1. “Top bird is the male wren, bottom the female. At the bottom is an oscillogram with the male and female parts marked in blue and magenta, respectively. The female initiated the duet, and the male moves its beak in its first interval but did not produce a syllable (1.11 to 1.36 seconds in the movie).”

Movie 2.  “This movie shows duetting in a captive pair of plain-tailed wrens. The bird visible at the start of the movie is the male, and the female becomes visible in the upper right hand corner. At the bottom is an oscillogram with the male and female parts marked in blue and magenta, respectively. Singing-related movements can be seen in both birds, but is particularly evident in the tail of the female at the end of the duet.”

And some audio recordings from the paper, showing both duets and single-sex songs:

Audio S1 Audio recording of the plain-tailed wren duet song shown in Figure 1A.
Audio S2  Audio recording of the solitary female plain-tailed wren song shown in Figure 1A.
Audio S3  Audio recording of the plain-tailed wren duet song shown in Figure 1B.
Audio S4 Audio recording of a solitary male plain-tailed wren song shown in Figure 1B.
Audio S5 Audio recording of a plain-tailed wren duet song in which the male skips a motif, as shown in Figure 1C.


Fortune, E. S., C. Rodríguez, D. Li, G. F. Ball, and M. J. Coleman.  2011.  Neural mechanisms for the coordination of duet singing in wrens.  Science 334:666-670.

Computer chip replaces cerebellum in a rat

September 30, 2011 • 10:20 am

The amazing results reported in this piece from New Scientist, “Rat cyborg gets digital cerebellum,” haven’t yet been published in a scientific journal, but were reported in a meeting in the UK.  The details are sketchy, but scientists apparently built a computer chip using information from the inputs of a rat’s brainstem to its cerebellum as as well the output generated by its input.  (The cerebellum, a lumpy part of our brain located underneath and at the rear, is, among other things, responsible for motor control of the body based on input from the brainstem.)  How they got this information onto a chip is also unclear to me, but I trust some readers will enlighten us.

Once they made the artificial cerebellum-chip, they used it to see if it could substitute for the real one in an elementary brain-processing task.  As the journal describes:

To test the chip, they anaesthetised a rat and disabled its cerebellum before hooking up their synthetic version. They then tried to teach the anaesthetised animal a conditioned motor reflex – a blink – by combining an auditory tone with a puff of air on the eye, until the animal blinked on hearing the tone alone. They first tried this without the chip connected, and found the rat was unable to learn the motor reflex. But once the artificial cerebellum was connected, the rat behaved as a normal animal would, learning to connect the sound with the need to blink.

The journal also reports that another group used electronics to replace lost memory in rats.

While there are substantial differences in how brains process information versus computers, there isn’t any reason why computer chips couldn’t replace many of the functions of the brain.  It’s intriguing to contemplate, for example, the possibility that a computer chip might one day help blind people to see, or improve memory in those with diminished capacity.

A striking case of predator avoidance in fish

September 30, 2011 • 5:38 am

This YouTube video, sent in by a reader, shows how a school of fish reacts to hunting behavior of blacktip sharks (Carcharhinus limbatus) off the Maldive Islands.

Notice how the fish seem to move in a coordinated fashion, almost as one, and how they tend to group behind the sharks, where they’re less liable to be nommed.  Such “coordinated” group movement is not unusual in flocking animals; we’ve seen it before in the amazing behavior of flocks of starlings (see the videos here).  The thing is, biologists don’t really understand what cues animals use when groups of them appear to move as one.

It hasn’t escaped my notice that the sharks seem to be driving the fish toward the wharf, perhaps to either trap them or stun them against the pilings. (Dolphins, by the way, sometimes stun prey by whacking them with their tail.)

I asked my colleague Steve Pruett-Jones to watch it and, as an animal behaviorist, send me his take. Here it is:

Animals form large groups for many reasons, from reproduction to migration to avoidance of predators. Some of the largest groups of vertebrates are seen when birds flock and fish school as an anti-predator defense.

This amazing video illustrates the apparent coordinated movement of individuals in a large school, although in fact the movement of each fish is thought to be independent. How the fish do this remains somewhat of a mystery. Obviously, vision is critical (fish don’t or can’t school after dark, and fish that have been blinded also don’t form schools) but fish also often have prominent markings on their shoulders or tails (schooling marks) which appear to serve as reference marks indicating their movement.

Other possible cues include pheromones, sound, and the sensitivity of a fish’s lateral line. Fish that have had their lateral line removed swim closer together, suggesting that the lateral line keeps fish at a minimum distance from each other; fish appear to be able to ‘feel’ when another fish comes close because the lateral line is sensitive to pressure. In contrast to the fish avoiding the sharks in this video, the movements of the sharks are clearly coordinated as it is in many predators.

By “independent” above, Steve means that the fish are not all responding to a single external cue (which may in fact be what the sharks are doing when they make their “hunting rush” in this video), but to the presence of surrounding fish.  This suggests two things: first, that this “coordinated” behavior is really a response to the movement of a single individual, who sets off a wave that propagates through the group.  Second, the speed of propagation seems much faster than can be explained by the sum of the reaction times of all the individuals.  The fact is that we simply don’t yet understand how this type of group movement works.  That seems like a simple question, but it’s a simple question that’s hard to answer.

h/t: Krishan