Sometimes people walk around with only half a brain, or a large portion of their brain disconnected, or simply having never developed, or an extra large brain, and we usually take little notice. But when there is a five or ten or twenty percent difference between two groups of people we are quickly willing to use that to decide (as in the Bell Curve) that those people with the (on average) smaller brain are inferior. The fact that all the well known studies comparing groups of living people that show such differences have been shown to be bogus (i.e. made up or doctored data) is often ignored.
Anyway, the following is the abstract of a 1998 paper by M. Henneberg that is still relevant of some interest:
1. The hominid brain has increased approximately three times in size since the Pliocene, but so has the brain of equids. The tripling of hominid brain size has been considered as an indicator of increased mental abilities, as it coincided with the production of tools, weapons and other artefacts of increasing sophistication. No indicators of the increase in equid intelligence are known. Intraspecific correlation between brain size and variously measured 'intelligence' is, in modern humans, very weak if not completely absent. With the exception of size, there are no major differences between the anatomy of ape and human brains.
2. A study of 297 estimates of body height, 626 estimates of bodyweight and 276 estimates of the cranial capacity of hominids dated at various periods over the past 5 million years shows that the increase in hominid brain size was paralleled by an increase in body size.
3. In a sample of 45 variously dated fossil hominids, brain size correlates isometrically with body size.
4. Since the Late Pleistocene (approximately 30 000 years ago), human brain size decreased by approximately 10%; yet again, this decrease was paralleled by a decrease in body size.
5. Therefore, it may be concluded that the gross anatomy of the hominid brain is not related to its functional capabilities. The large human brain:body size ratio may be a result of the structural reduction of the size of the gastrointestinal tract and, consequently, its musculoskeletal supports. It is related to richer, meat-based diets and extra-oral food processing rather than the exceptional increase in the size of the cerebrum. The exceptional mental abilities of humans may be a result of functional rather than anatomical evolution.
There are earlier and later papers that indicate or support similar ideas, but this is the nicest summary.
Ah, but longevity is correlated with intraspecific body size.
With the exception of size, there are no major differences between the anatomy of ape and human brains.
Unfortunately I do not have access through my institutions' intranet (I can try my University proxy later). But I rather suspect this statement is incorrect.
Perhaps there are no major differences in macroscopic anatomy, in fact I seem to recall a seminar recently that refuted a few proposed macroscopic differences, but I seriously suspect that there are structural differences, beyond receptors and intrinsic cellular properties, underlying apes and humans. I guess it depends on what someone considers major, but at the small circuits level a shift in dendritic arbors can make an enormous difference.
Well, there are bound to be some important differences. Otherwise, we'd all be in a Charlton Heston movie.
Yeah, I guess the sort of stuff I'm talking about is probably what the author is calling 'functional', it just irks me to see the structure part left out. Differences don't appear out of nothing.
Bear in mind, though, that human brain size could be correlated with intelligence (say) even if the reason why humans are more intelligent than other animals is nothing to do with brain size.
Those are two separate issues.
Since I am curious enough about this topic I just did a pubmed search and found a nice, and free, review:
Rushton and Ankney 2009
Whole brain size and general mental ability: a review.
There appears to be a modest correlation, estimated about 0.4, but there are so many confounding factors to consider, and I have not read through the entire article (just the first section, so far).
Sam, you may not be aware of this but Rushton's work is long discredited.
I am not aware of it, and I found the size of the correlation to be incredibly surprising, and perhaps the result of confounding factors. I also have never read any articles from that journal before (International Journal of Neuroscience), so I am not buying it just yet, but my plan was to first read through it, then to seek out critiques.
If you know of a particular authority to look up for a critique of his claims, I would appreciate it.
Studies looking at whole brain size across species are bound to miss the point. Whole brain size relates to many functions, as you post. Abstract cognition principally relates to some specific brain areas. The differences between H sapiens and other primates are not just gross size but also fraction of brain volume in pre-frontal cortex. See the chapter of evolution of the frontal lobes in Miller & Cummings. I don't know specifics of horses, but would be willing to bet that they don't show the same specificity of prefrontal cortex expansion.
As for comparisons between humans, whole brain size is too coarse a measure to be meaningful. For instance, a large brain may not be a good thing: brains of children with autism are enlarged relative to normal controls (Redcay Biol Psychiatry. 2005 v58(1):1) and there are a number of neurological diseases associated with large brains.
I don't do homework for the ittle boys but "duh, I never heard of Rushton but but I will be happy to uncritically accept his claims and since there is nothing in front of my bald eyeballs suggesting otherwise you must do the work necessary to lift the veil from my eyes" is not ok from someone who claims to be a biology grad student.
Otherwise, we'd all be in a Charlton Heston movie.
Wayne's World 2?
I vaguely recall an article on brain size in various smart dead people. I think there was about a 25% spread in brain volume. Anatole France had the smallest one measured.
Anatole France had one of the smallest brains ever measured in our species among "normal" headed people (i.e. excluding microencephalitics etc.)
- It's an organ using 20% of the body's energy and 35% of the oxygen or something, yes? Are we saying the amount of this stuff, which must affect energy consumption, really has no correlation with brain performance? What's the theoretical justification?
- The brain's not a quite a computer neural net, and the performance of even those depends on more than the number nodes and the count of connections, but it just seems strange that the performance of any net should be size invariant.
- At childbirth - which has been (and still is) absurdly dangerous in human women - the head's the largest part of the body, I think. That would indicate some "significance" at least to head (not brain directly but presumably that's the point) size in infancy.
Anyhow. Arguments from metabolism, evolution and basic intuitions about how networks behave. I'd want good reasons to reject these, even if you say some studies say otherwise - data can be wrong too when theory and observation collide.
I'm not sure I have much that's really original to add to this discussion, but I would like at the very least to summarize the salient points made by earlier commentators â and make some, oh I don't know, "meta-comments"?
1. Point #5 in M. Henneberg's abstract makes some critical and valid points but is clumsily worded in at least two places: (1) "it may be concluded that the gross anatomy of the hominid brain is not related to its functional capabilities." This is true to a certain extent; but at what point does "gross anatomy" end and microscopic anatomy, or for that matter circuitry, begin?! Although we now know that certain gross-anatomical features (e.g., gyral patterns; shapes of major lobes) are epiphenomena in the usual contexts in which they are discussed, for "gross anatomy ... [to be] not related to .... functional capabilities" would constitute, if true, extreme functionalism and/or vitalism.
2. Regarding Sam N's comments: (2) Indeed while much remains unknown about human- and non-human ape brain differences, it is not the terra incognita it was even thirty years ago. So yes, there are major known differences in internal brain allometry, cytoarchitecture, neurochemistry, developmental neurobiology, neuropathology, and gene expression. Practical and ethical constraints prevent us from knowing as much about ape (including human brain) connectivity as we know about monkey connectivity, but substantive circumstantial data (e.g., from "comparative hodology" [add THIS definitive review of the field to your library for a mere $2K: http://www.amazon.com/Central-Nervous-System-Vertebrates-Poster/dp/3540… ] point to major differences in human- vs non-human-ape circuitry as well. (4) Sam N's remark that "Differences don't appear out of nothing" is a point I absolutely agree with and addressed in #1 above. (6,8). I agree with Sam's discomfort from arguments-from-authority, and I wish I had ready access to the peer-reviewed critiques of J. Phillipe Rushton; unfortunately I don't have a photographic mind. For now, see: http://en.wikipedia.org/wiki/J._Philippe_Rushton . The two-fold point to bear in mind when reading Rushton's work, however, is that he has a long (and as Elizabeth points out in (7) discredited history as an anachronistic academic fraud with a racist axe to grind regarding supposed lower intelligence of blacks (and highest intelligence among Asians) using anthropologically obsolete racial typologies, oversimplified life-history theory, and psychologically flawed analytical techniques. His most flagrant papers are self-published, and I recall that a few years ago he mailed out a little green 'book' summarizing his egregiously misleading work to me and hundreds of other biological anthropologists. I kept it as an odd memento of physical anthropology's Dark Side but eventually tossed it into the trash where it belonged all along. Secondly, regarding publication in journals of physical anthropology/human biology: Investigate the historical provenance of these various journals if you can. Check out just who is on the editorial board. Some extant journals actually originated in the Victorian era (in order to publish colonialist-apologetic counterarguments to the â by the standards of the day â anti-racialist conclusions of Huxley and Owen et al.) and retain a strong racist bias. Many biological anthropology journals, however, have an underlying (inclusionary AND exclusionary) editorial paradigm: sometimes it is evolutionary psychology ("sociobiology"), sometimes mammalian ecology, sometimes very specific phylogenetic-analysis methods. Unfortunately the literature of physical anthropology in general and hominid brain evolution in particular is riddled with methodological and theoretical biases. Caveat lector!
3. David's points (9) are right on.
4. Regarding Jim Thomerson (12) and Anatole France (13). Steven Jay Gould's The Mismeasure of Man http://www.amazon.com/Mismeasure-Man-Stephen-Jay-Gould/dp/0393314251 and http://en.wikipedia.org/wiki/The_Mismeasure_of_Man remains the classic intellectual "starting point" for discussions (pro and con) concerning brain size and intelligence. Reading about the predictions and findings of the "Mutual Autopsy Society" is especially fun. Sometimes I wish it was still in existence: Wouldn't it be fun to dissect our colleagues over a glass of claret?
5. Concluding comments relative to Greg's provocative post "Human Brain Size: Does it matter? And has it decreased?"â (a) Allometry (what Julian Huxley (1932) termed "Problems of Relative Growth") http://en.wikipedia.org/wiki/Allometry is always a necessary starting point. (b) Phylogenetic biases must also be "subtracted out" [ http://www.amazon.com/Comparative-Evolutionary-Biology-Ecology-Evolutio… ] e.g., by statistical programs such as CAIC (Comparative Analysis of Independent Contrasts) http://www.bio.ic.ac.uk/Evolve/software/caic/index.html (c) Once you've statistically cleansed/massaged/created your brain-body size data, how do you use it? We can often inferentially describe specific hominid brain anatomy and trends in brain size, but what good does that do? Obviously there need to be testable hypotheses involved and evolutionarily solid (as opposed to "Just So") stories involved ...
(d) I shall resist swallowing the rest of Greg's bait. This is a very complicated field and the worthwhile literature (i.e., scientific research of lasting value) on human brain size evolution easily exceeds two thousand papers and monographs. (I myself have agonizingly plodded through at least 1500 of them, in the course of earning my Ph.D. in Biological Anthropology with a specialization in human brain evolution.) (d) So to previous commenters on this post who might reply "Can't you just give us the bottom line?!" I'll offer Professor Terrence Deacon's (UC-Berkeley Departments of Anthropology and Neuroscience) six-word summary when it comes to brain size: "BIGGER IS BETTER" IS A FALLACY. http://www.springerlink.com/content/y4uj17513610xh84/
Did you folks hear about the people with various degrees of hydrocephalus, studied by John Lorber (see http://en.wikipedia.org/wiki/John_Lorber.) Many had little brain matter left, but still IQs up to 126. It's a shame, it didn't get more attention. I think that's because it couldn't be explained, and was an annoying situation to the view that we understand intelligence and brain function.
Thanks for the brain post Greg. I did find several similar articles (though never found the one you recommended) and have learned many interesting things from the articles and links. But alas, I was not able to find anything regarding the more surprising statement you made, that HG brains tend to be bigger in extant humans. Perhaps I misunderstood your meaning (though some others seem to have gotten the same impression).
The brain size for extant human groups requires some digging (I did not know that was what you are looking for). I doubt you would be able to easily find that. Nor can I easily dig it up right now. I'm geared up for entirely different projects and that literature is deeply filed away. You 'll just have to go along assuming it's not true as you are obviously not prepared to take my word for it. You'd be wrong, of course, but I can't help you with that right now.
The data I have are estimates for Pygmies, Hiwi and Inuit. In addition to that, there are data from recent individuals of San/Bushmen .... holocene age ... which you probably could find in the literature.
What is most impresive to me, though, is a) there is a big drop at 30K and another drop in agricultural populations after 10K. Those are strong signals of something. This has been suggested (by Wrangham among others) as similar to what happens when animals are domesticated. The smaller brain goes along with reduced muscular robusticity in both domesticated animals and in humans.
oh, and b) how easily and uncritical people will accept statements that OTHER people's brains are smaller than YOURS but how when the opposite is proposed, THERE MUST BE EASILY ACCESSIBLE LINKS!
(Sorry, I just find it mildly annoying and amusing at the same time ... I think Elizabeth may as well.)
Neil: Yes, exactly!
Something I 've not metioned because it does get off topic ... brain to x correlations (where x is any measure) within species are generally bogus. Unless of coruse it is the other guys brain being smaller, then that's OK. Between species in a genus, such relationships are usually also bogus. The phylogenetic effect in brain size is strong.
Folks, I just freed a comment by Joe M. Joe seems to want to remain at least semi-pseudonymous but I'll tell you that he is someone I've known for years, and respect a great deal. He and I had the same mentors in the study of brains, the difference being that Joe's actual research has been on brains and he knows as much about brain evolution, anatomy, and stuff as anyone. So you are getting some real expertise here. Trained a major east coast University that shall remain unnamed because it would just make you feel inadequate.
", is a) there is a big drop at 30K and another drop in agricultural populations after 10K. Those are strong signals of something."
Were they both accompanied by a decrease in body size? Seems like it may be related to diet.
"d b) how easily and uncritical people will accept statements that OTHER people's brains are smaller than YOURS but how when the opposite is proposed, THERE MUST BE EASILY ACCESSIBLE LINKS!"
Hey I tried to find the information on my own and could not as you confirm above:
"I doubt you would be able to easily find that. "
Which also btw seems to counter the idea that this knowledge is practically 'axiomatic' as you claimed earlier.
I don't know if you are serious and directing your comments at me or just elizabeth, but I wouldn't have thought any group's brains are either smaller or larger than any other's as far as extant human populations are concerned, and either assertion would have equally surprised me. (I assume this is all relative brain size we're talking about) I'm prepared to believe it, but not without evidence of course. I don't know why everyone is making such a big deal about me simply asking.
Isabel: The knowledge that I "claimed" to be virtually axiomatic, and is, consists of the drops in brain size in the late Pleistocene and early Holocene. I did not understand until your comment above that you were actually looking for data on contemporary populations. And that, as I said, is not virtually axiomatic.
So I am both doing your research for you and keeping it straight for you! You need to be doing some of this work for yourself too, you know.
I don't know if you are serious and directing your comments at me or just elizabeth, but I wouldn't have thought any group's brains are either smaller or larger than any other's as far as extant human populations are concerned, and either assertion would have equally surprised me.
That is largely rue. The ONLY living groups that stand out as having brains relative to body size that are larger, that I know of, are Inuit and Pygmy.
Phrenology was a "big science" up til the 50's that was debunked during the 40's til the 70's and has not been considered serious science for over 50 years. You might want to look up Brocas Brain and the University of Paris. Other universities have probably kept their studies of phrenology and I have doubts that much of the information would be on the web.
"So I am both doing your research for you and keeping it straight for you! You need to be doing some of this work for yourself too, you know."
WTF are you crazy? You just admitted I probably couldn't find this information on my own (and thanks for clue-ing me in AFTER I spent 20 minutes searching fruitlessly for any information related to your sensationalist claims).
Thanks for the informative post, Joe.
Isabel, I'm not sure that a "blog" is what you think a "blog" is. There are widespread resources on brain size. Which you an find if you want. (But you have to calibrate your standards. 20 minutes is not a lot of time). However, this ONE thing ... these data sets for various forager groups ... are not going to be easy to find . They are in the primate literature, not the human literature, and, I guess I should have mentioned this earlier but I didn't realize it necessary ... they are (likely) NOT on the internet.
They are of course on a spreadsheet I've got somewhere but I haven't looked at this stuff in years.
My claims are not sensationalist. And you are starting to wander into territory that is disrespectful. I am a fairly busy person. I blog what I can blog, when there is a topic I'm working on I can easily be a go-fer for someone who asks, but there are limits.
You know, Isabel, it will take you far more than 20 minutes to read and run down the information in and truly understand Dr. Joe M's comment above. And it will be very worth while. Go do that and report back with questions and between Joe and I we'll probably be able to guide you through further work.
Why would some people have bigger brains if there was not some benefit? Look at the smartest people, the leaders of today in all fields, they have big heads. East Asians have the biggest skulls and the highest IQ's.
"There are widespread resources on brain size. Which you an find if you want."
You just admitted it would not be easy for me to find, or even for you to find.
"I did not understand until your comment above that you were actually looking for data on contemporary populations. "
This was clearly stated three times. What was so hard to understand?
And Pulleeze ANOTHER lecture about what a blog is?? And offering me an alternate education? No thanks. I call bullshit on your whole idea of larger brains and higher intelligence in HG's. yeah I get it science blogs is a place to spew random thoughts and sensationalist claims, after all it's YOUR blog and you should be able to make up any shit you want.
Isabel, you have gone over the top. I am pretty sure any normal person looking in would understand that you are not reading the responses I"m giving you. We are talking about two distinctly different things, one spoken of widely in the literature, the other .... oh, fuck, never mind.
Just sit tight. I will get all the data for you, including papers written, references to books and book chapters, raw data I've got laying around, and obscure references that have not made it to the internet yet.
But this might take a while....
Over the top? I don't understand that "we" are talking about two different things? Oh, please don't bother educating me any more. I don't care that much. Just keep posting 900 new posts a day.
I think to make the following assertions in your first post, that apparently cannot be backed up except with personal, limited data that you are too busy to provide is pretty irresponsible. But that is because, as CPP would say, I just don't understand what blogging is all about.
"We don't have IQ data on hunter-gatherers, but we do have some brain size data. Absolute and relative brain size is larger for hunter gatherer populations, both living and prehistorically."
"It is distinctly possible that the non-hg Euro-farmers are simply innately not as smart as foragers. The brain size is different. Sorry. You might have to live with that fact."
"But prior to agriculture, human brains were larger world wide, and today the large brains popluaton wide seem to be in HG groups. Plus, having living in "Western" settings most of my life and with "HG"s for a substantial period of time, I just think from personal experience that they're smarter."
Isabel != have + clue
I WISH TO RECOMMEND A BOOK for motivated readers of Greg's blog, and of this thread in particular. Of course I can't know which GLB readers this applies to, since we all come to this virtual place with a variety of backgrounds, interests, and (yes!) baggage. Also, my recommendation is slightly "off-topic" insofar as it does not directly address our understandably anthropocentric interest in human brains, nor the focal problems (paleoanthropological trends and contemporary intergroup variation in brain size) highlighted in this thread. That being said, EVERY reference I recommend below treats the topic of evolutionary changes in brain size in substantial detail. (Sorry, Isabel, my training was too long ago to be of use to your apparent interest in hunter-gatherers.) Anyway, here goes:
Studying human brain evolution has been contentious ever since Darwin and Wallace famously disagreed on the extent to which the topic was even susceptible to scientific explication. ["Natural Selection and the Human Brain: Darwin vs. Wallace," by Stephen Jay Gould, 1992. Chapter 4 in "The Panda's Thumb" http://www.amazon.com/reader/0393308197?_encoding=UTF8&ref_=sib%5Fdp%5F… ]. But in one important sense all the problems and questions of this immense field differ not one whit from those in other academic fields: Facts need theories and vice versa. I'll go one further and say there is no "factual" matter concerning human brain evolution, no matter how scrupulously circumscribed, that isn't empowered or hobbled (and sometimes paradoxically both) by its associated principles.
It is with this truism in mind that I suggest that all would-be or already-committed [in- or out-of asylum] students of brain evolution, whether their primary interest rests in comparative intelligence, neuroanatomy, evolutionary psychology, paleoneurology, or brain-size allometry (etc.), not just read but OWN UC-Irvine Professor George F. Striedter's text "PRINCIPLES OF BRAIN EVOLUTION" (2005, Sinauer) http://www.amazon.com/Principles-Brain-Evolution-Georg-Striedter/dp/087… â Minimally, you should take advantage of Amazon's "Click to look inside" feature at the foregoing url. This is by far the best (it may be the only) recent book-length treatment of our subject that lives up to its title. (John Allman's theoretically eclectic (as opposed to synthetic), gorgeously illustrated "Evolving Brains" (2000, W.H. Freeman: Scientific American Library, 240 pp.) http://www.amazon.com/Evolving-Scientific-American-Library-Paperback/dp… is a distant runner-up.) Other indispensable reference books that address brain evolution principles and theories include, for example, Nieuwenhuys's 2219-page synthesis of the past century's comparative/evolutionary brain research, recommended in my earlier post (#14 above); this massive three-volume compendium is primarily organized taxonomically: it tries not to be hobbled by the scala naturae fallacy and mostly succeeds. In contrast, Butler and Hodos's (2005) landmark textbook "Comparative Vertebrate Neuroanatomy: Evolution and Adaptation" (Wiley-Liss, 744 pp) http://www.amazon.com/Comparative-Vertebrate-Neuroanatomy-Evolution-Ada… is organized anatomically by brain regions: this is a well-written review of comparative neuroanatomy, jam-packed with black-and-white anatomical drawings, which you can dip into to discover how, for instance, hippocampal or cerebellar organization differs by vertebrate clade. Still other outstanding books address a specific problem in brain evolution, e.g., brain-language coevolution (e.g., Terrence Deacon's Staley Prize-winning "The Symbolic Species" (1998, Norton) http://www.amazon.com/Symbolic-Species-Co-Evolution-Language-Brain/dp/0…); or perhaps argue for a prime mover as the cause of hominid neocortical expansion (e.g., climate change in William Calvin's work, or social complexity in Robin Dunbar's, etc.); or offer a comprehensive review of the entire field: e.g., David Geary's (2005) "The Origin of Mind" (American Psychological Association, 459 pp.) http://www.amazon.com/Origin-Mind-Evolution-Cognition-Intelligence/dp/1… This last book is invaluable as a wide-ranging critical review (e.g., 84-pages (!) of references), although a robust background in both cognitive neuroscience and neuroanatomy seems necessary to evaluate the author's modular-intelligence arguments. [Cf. "Without a theory the facts are silent" (Friedrich August von Hayek) vs. Thomas Henry Huxley's "... a beautiful theory ... killed by an ugly factâ vs. the second paragraph in my post.]
But back to Georg Striedter's "Principles of Brain Evolution" â His ten chapter titles broadcast the strength of this book's organization and content: Evolutionary Neuroscience: This Book's Scope and Ambition; A History of Comparative Neurobiology; Conservation in Vertebrate Brains; Evolutionary Changes in Overall Brain Size; Evolutionary Changes in Brain Region Size; Evolutionary Changes in Brain Region Structure; Evolution of Neuronal Connectivity; What's Special about Mammal Brains?; What's Special about Human Brains?; and finally, Reflections and Prospect.
I should say outright that I have no academic or personal ties to Dr. Striedter (other than speaking once at a conference he chaired) and don't necessarily agree with his strong cladistic approach. But his colloquially written, data-rich, allometrically, phylogenetically and developmentally informed 436-page book is (as advertised "advanced textbooks" go) small (9.5 x 7 x 1 inch thick, with a generous allocation of graphs, anatomical illustrations, even large margins. Hence very reader-friendly but â most importantly â a biologically sophisticated and painless PREREQUISITE, I feel, for delving into the more parochial and sometimes neuroanatomically naive articles on hominoid brain size that we've been alluding to in this thread. (Although you can always take the alternative route of pursuing your doctorate under one of the (in this country) dozen or so legitimate experts in human brain evolution ... Let's see: $60 for "Principles of Brain Evolution" vs. $300,000 (at least!) for a Ph.D. Hmmmmm.) Some of you guys might find it worrisome that Striedter's own laboratory research focuses on fish and bird brains, but I think that's a strength: especially when there is â to the best of my knowledge â no comparably superb or equivalently synthetic book-length treatment of hominoid brain evolution written (recently) by an anthropologist, even though four or five excellent book chapters do come to mind. (The examples most relevant to the discussions of this thread are Terrence W. Deacon's 1997 "What makes the human brain different?" http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.anthro.26.1…, and several more recent articles/book chapters by Emory University's Dr. Todd Preuss http://research.yerkes.emory.edu/Preuss/index.html .)
Brain References Recommended by Joe (above)
Note (Re: Post #31): The url to my penultimate reference above was incomplete, and should have read: http://arjournals.annualreviews.org/doi/abs/10.1146/annurev.anthro.26.1…
Deacon, TW. 1997. What makes the human brain different? Annual Review of Anthropology 26:337-357.
ABSTRACT: "Despite decades of research that has revolutionized the neurosciences, efforts to explain the major features of human brain evolution are still mostly based on superficial gross neuroanatomical features (e.g. size, sulcal patterns) and on theories of selection for high-level functions that lack precise neurobiological predictions (e.g. general intelligence, innate grammar). Beyond its large size we still lack an account of what makes a human brain different. However, advances in comparative neuroanatomy, developmental biology, and genetics have radically changed our understanding of brain development. These data challenge classic ideas about brain size, intelligence, and the addition of new functions, such as language, and they provide tools with which we can test hypotheses about how human brains diverge from other primate brains." Hopefully you'll have access to a library (or I.L.L.) for the Full Text.
"Sorry, Isabel, my training was too long ago to be of use to your apparent interest in hunter-gatherers."
Actually my interest (before it was dampened by the hostile response to my question and accusations of racism) was in the existence of different relatively and absolutely sized brains in different human populations that may lead to differences in intelligence, as was alluded to earlier in this series.
Thanks for the links!
n the existence of different relatively and absolutely sized brains in different human populations that may lead to differences in intelligence, as was alluded to earlier in this series.
There isn't any valid evidence in support of this idea. JPR's work, referred to above, is the most vigorous attempt to correlate brain size with IQ (as one way to do it) and that required fudging the brain size data so "Africans" had smaller brains, and fudging the IQ data as well.
The only groups that seem to have different brain sizes among living humans are some forager groups, the data for which are being held hostage by the meanie blogger, but those data sets are so small as to not be definitive, and there are no IQ data. The meanie blogger, having lived with one of these groups for a couple of years, thinks they are really really smart, smarter than most people he's met in Teh West before or since. But that is his own personal experience and when he says that to white western people they tend to get all hot under the collar because they don't like getting intellectually outflanked by little black people who "still" live in the jungle and so on.
Joe M. -
For reasons not entirely related to the current discussion, a couple of my profs have recommended both the Georg Striedter and Terrance Deacon texts you mention. I am curious what (if any) thoughts you have about Merlin Donald's work on the evolution of consciousness. He was also recommended by my anthro prof and a couple of random internet commenters.
I should note that my interest is in evolutionary psych, which eventually (if and when I end up in academia) I wish to turn into an exploration of the evolution of abnormal psychology.I have definitively more interests than that, but I am hoping to stay moderately focused...
"But that is his own personal experience and when he says that to white western people they tend to get all hot under the collar because they don't like getting intellectually outflanked by little black people who "still" live in the jungle and so on."
It sounds like you are getting some personal satisfaction from the idea that people are getting 'hot under the collar' (not that there has been any sign of that here that I can see) - makes you feel 'so not a racist' and therefore superior to other people I guess.
But yes, you did imply there was a physical basis. It seems like you are now denying that you did so.
It seems like you are still calling me (or someone- who?) a racist - well, welcome to science blogs.
Sorry, I never got the chance to read Merlin Donald, though I do have his first book ... if I only knew where! If I recall correctly, he is a respected scholar, and one of a cadre of writers on the evolution of language (cf. Pinker, Bickerton) who have not rigorously addressed the neuroanatomical substrates involved. And, academic nepotism aside (Deacon was my graduate advisor), "The Symbolic Species" is still considered THE watershed book on brain-language co-evolution: that's why it's still selling so strong after ten years. Terry Deacon is unique in terms of his dual neuroscientific and linguistic/semiotic expertise. Brown University's engineer-turned-cognitive/linguistic neuroscientist Philip Lieberman has also researched the evolution of language, focusing initially on the vocal substrates and more recently on the role of the basal ganglia.
As for evolutionary psychology-cum-psychopathology, that is already a huge field. Your interest in evolutionary psychopathology strikes me as awesome; this is definitely one hot field these days, as is evolutionary medicine generally, and you may be able to do some pathbreaking work if you get into evolutionary psychopathology now, at a time when nearly every expert agrees that the DSM-IV (and soon to be substantially revised DSM-V) are pseudo-naturalistic, nosological nightmares (to put it kindly). Yet your concern about spreading yourself too thin is â as I, and I suspect Greg too can experientially confirm â the frustrating-but-legit flip side to the joy of intellectual eclecticism. Evolutionary psychopathology might look "narrow" to you at this juncture, but once you get more deeply immersed you'll find it quite broad â not even a "moderate focus" at the Ph.D. level â and then your challenge will be to carve out a manageable sub-niche within it. Sorry, but that's just the way academia works: you must learn more and more about less or less, or your career will be toast. One interesting thing about evolutionary psychopathology is that, if you play your cards right, you should be able without a whole lot of difficulty to combine clinical (= bread-winning) and research (= academic-career) tracks into some sort of dual degree. Of course, you'll have to do some critical homework on WHERE to study "if and when" you do choose that route.
All other academic variables being equal, your most important considerations for graduate training in evolutionary psychopathology will be (a) the expertise of your mentor (graduate advisor); (b) your personal and intellectual fit with your mentor; (c) the sholarship/grant resources said mentor can funnel your way; and (d) his/her track record in turning out professionally successful scholars. (And alas, it is (c) â combined with whether or not your advisor has tenure â or, if not, might desert you half-way through your 6-year doctoral commitment â which may turn out to be paramount.) Whatever else you do, if you are serious about obtaining advanced training in this field, be sure to contact DR. MELVIN KONNER, MD, PhD., professor of Anthropology and Psychiatry at Emory University for guidance/advice.
Back to Merlin Donald .. and other potentially useful readings. I'm not going to recommend the usual suspects in evolutionary psychology, as I'm sure you've already apprehended those on your own. But here are three books that I've found personally interesting and challenging although, I must warn you again, evolutionary psychology is definitely NOT my forte:***
1. Brune's (2008) "Textbook of Evolutionary Psychiatry" http://www.amazon.com/Textbook-Evolutionary-Psychiatry-origins-psychopa…
2. McGuire and Troisi (1998) "Darwinian Psychiatry" http://www.amazon.com/Darwinian-Psychiatry-Michael-McGuire/dp/019511673…
3. Plotkin (1998) "Evolution in Mind" http://www.amazon.com/Evolution-Mind-Introduction-Evolutionary-Psycholo…
***Notwithstanding this disclaimer. I cannot resist mentioning that Greg and I (cue up a chorus of Auld Lang Syne) were Teaching Fellows for "Human Behavioral Biology," a huge general-ed natural-science course taught at Harvard by Irv DeVore and Terry Deacon, back before Tooby and Cosmides were even toilet-trained. Ok, that last part's an absurd lie: we're not quite THAT antediluvian ... OOPS! Gotta go wipe the drool off my keyboard.
Thanks Joe, not only for the response, but also the confirmation that Greg is as elder like as I always suspected be is...
Seriously though, I am still developing my plan and have a little bit of time in which to make decisions. I am increasingly bent on the study of evolutionary psychopathology, but I am also very enthusiastic about addiction and the development of an addiction treatment model - ultimately in a fairly significant overhaul of our current social addiction paradigm.
Though I am also learning that these aren't necessarily mutually exclusive.
What I mean by the narrow focus comment though, is that I also have a rather profound interest in the evolution of religion and rudimentary culture, as well as several other aspects of evolutionary psych. I realize that I really have to increasingly focus myself as I progress - it doesn't mean that I can't damned well resent the necessity:)
On the upside, my partner is heading into bio-med. So as long as I can convince her to put up with me indefinitely, I will be pretty free to pursue an entirely academic career - yet live like a full time therapist. Though in all honesty, I am not sure I won't spend quite a bit of time doing that too. I am actually pretty keen on practical applications and hell bent on our society dealing with addiction a hell of a lot more sensibly than we do now.