I'm rereading a terrific paper by Kathryn W. Arthur (2010), in which she describes the acquisition and development of stone tool manufacture and maintenance among a group of Konso women in SW Ethiopia (the stone tools they produce they subsequently use in hideworking) . While I'll have much more to say about it in its own right, since I've been doing a bit of thinking about prehistoric heat treating of lithic raw material these past few days, I was struck by this passage:The majority of hideworkers using chalcedony and milkyquartz begin production by heat treating the raw material tomake it more brittle for reduction. The hideworker placesthe raw material on top of a broken piece of pottery withan insulator such as leaves, domesticated animal hair, wool,cotton, or additional pottery sherds in a pit under her hearth.There she leaves the stone for as little as 12 hours and up to three months. Once she “cooks” the stone, she then letsit cool for at least one day. Konso women knappers usedifferent heat-treating methods based on the size, type, andquality of the raw material to increase the flakeability of thestone. (Arthur 2010: 234, emphasis added)If this account is at all a reflection of what went on in prehistory, this is a huge span of time during which material is exposed to heat. And this observation got me to thinking about the recent study by Brown et al. (2009), where they determined that Middle Stone Age hominins in southenr Africa by 72,000 years BP at the site of Pinnacle Point 5-6 (and maybe as far back as 164ky BP in the area as a whole), used 'pyrotechnology' to alter the properties of locally obtained silcrete to make it easier to work, notably to produce fine bifacial points. Brown et al.'s study is especially noteworthy in that they propose what are, to my knowledge, the first set of objective criteria that can be used to both identify heat treatment as well as to quantitatively assess how much more 'flakable' stone becomes after heat treatment. These include thermoluminescence, archaeomagnetism, and gloss/reflectance. This in itself is a big step forward for future studies of heat treatment as they set a new level of analytical rigor that now has to be matched by future studies interested in demonstrating that heat treating took place in the past. It also establishes the need for experimental protocols in such efforts.Going back to the Arthur (2010) paper, though, I was struck by this section of the supplementary material provided for their study by Brown et al. (2009), in which they discuss their experimental protocol to replicate the effect of heat treating on silcrete:Two methods were employed to heat treat experimental silcrete samples. In the first, we placed raw material and a thermocouple probe (type K) within a sand bath approximately 2-3 cm below the surface. A fire was then built over the sand containing the silcrete. The temperature of the silcrete was slowly built up to ~350º C over a period of approximately 5 hours and then gradually cooled to ~40º C (usually overnight) before the blanks were removed from the sand. Temperature was monitored and recorded using a J-Kem HHM-40 handheld temperature meter and data logger. Fires required approximately 20 kg of dried hardwood per 3 kg of stone. In the second method, we heated samples in a Gallenkamp muffle furnace fitted with an external J-Kem programmable temperature controller (Model 360/Timer-K). The controller was programmed to slowly ramp the temperature of the furnace to 350º C over 5 hours. This temperature was held constant for 12 hours and then dropped slowly to 40º C before removal of the blanks. (Brown et al. 2010: S2-3)Now, this is clearly a different setting under which to heat material. Further, Arthur's ethnoarchaeological observations don't indicate how hot is the fire that lithic nodules are exposed to, not whether or not the 12 hours is more frequent than the three months she mentions as one extreme of the spectrum of heating duration. She also doesn't describe how much better the stone was after heating, or after different lengths of exposure to heat, and the raw materials being heated in both studies are also very different. These factors mean that it's not possible to directly assess the comparability of the Konso observations to those from the MSA at Pinnacle Point. However, if they are at all comparable, it does suggest that the lengths of time employed in Brown et al.'s replicative work woulf fall at the lower end of the durations for which lithic raw material must be heated to acquire better properties.Why does this matter? It matters because it has important implications for how long fires must have kept going in the past for heat treating to be effective. This, in turn, has implications for how much fuel must have been available for heat treatment to be a feasible undertaking. Perhaps most importantly, it also has implications about the labor that must have gone into tending these fires to make sure they didn't go out. If stone was heated continuously for, say, 24 or 48 hours, it implies that someone must have remained relatively close to that hearth for that duration, which imposes some limitations about how mobile that person (or those persons) might have been. If, as Arthur (2010) argues, women may have been in charge of some aspects of lithic production such as heat treating, it implies that males and females may have had different economic roles going back quite a ways in the Late Pleistocene, a topic we've discussed at AVRPI before.References:Arthur, Kathryn Weedman (2010). Feminine Knowledge and Skill Reconsidered: Women and Flaked Stone Tools American Anthropologist, 112 (2), 228-243 : 10.1111/j.1548-1433.2010.01222.xBrown, K., Marean, C., Herries, A., Jacobs, Z., Tribolo, C., Braun, D., Roberts, D., Meyer, M., & Bernatchez, J. (2009). Fire As an Engineering Tool of Early Modern Humans Science, 325 (5942), 859-862 DOI: 10.1126/science.1175028... Read more »
Arthur, Kathryn Weedman. (2010) Feminine Knowledge and Skill Reconsidered: Women and Flaked Stone Tools. American Anthropologist, 112(2), 228-243. info:/10.1111/j.1548-1433.2010.01222.x
Brown, K., Marean, C., Herries, A., Jacobs, Z., Tribolo, C., Braun, D., Roberts, D., Meyer, M., & Bernatchez, J. (2009) Fire As an Engineering Tool of Early Modern Humans. Science, 325(5942), 859-862. DOI: 10.1126/science.1175028
Before the event took place there was much consternation abuzz on the blogosphere over the cast of characters chosen to speak at the Faith and Science event held as part of the 2010 World Science Festival. Sean Carrol of Cosmic Variance being the first vocal critic with Richard Dawkins and Jerry Coyne re-posting Carroll's critique on their respective homepages. Other discussions of the event can be seen at Thoughts from Kansas, Uncertain Principles, and evolutionblog. The panel included evolutionary geneticist Francisco Ayala, cosmologist and physicist Paul Davies, biblical scholar Elaine Pagels and Buddhist scholar Thupten Jinpa.
Dr. Brian Greene - festival founder - kicked off the panel by getting in front of the audience and thanking his mother, brother, and two sisters - all in attendance - for their shared life of cosmic discussions. From this familial focal point he explained the purpose of the event - open discussion. He described the array of religious viewpoints in his own family and how, despite their differences, they are able to discuss big questions with open ears. Dr. Greene also took time to thank the foundations that made the festival possible.
This was my first time attending the World Science Festival as I signed up to volunteer months ago, otherwise I have no affiliation with WSF or any of the funding foundations. My thoughts are my own and I feel I am in a position to judge this event without bias. I have kept my finger on the pulse of the "new-atheist" vs. "religious apologist" debate for years and always come to the same conclusion. Talking about something controversial, whether it be cold fusion, God, or intrinsically disordered proteins, is better than not talking about it. I am a biochemist and not religious but I do see great value in discussion, even among those diametrically opposed. One of my favorite philosophers, Dr. Bernard Rollin said in thanking his colleagues at the front of his book Science and Ethics "Plato is right; thought is dialogue, people in lively discussion, not Rodin's isolated Cartesian." Though I understand the criticism flung at this event, I feel an event whose mission is to bring science into the public sphere must include such a discussion, as religion plays such a prominent role in the lives of so many around the globe.
Bill Blakemore, decorated journalist of ABC News, moderated the panel. He began by asking each panelist to give an image and a musical composition they felt best displayed the intersection between science and faith.
As a full disclosure, the two scientists on the panel - Dr. Ayala and Dr. Davies are Templeton prize winners. This fact is given as reason for the preemptive criticisms from the blogosphere as the Templeton prize awards a scientist each year that takes "remarkable steps affirming life's spiritual dimensions." The new atheists such as Richard Dawkins, and Jerry Coyne have taken to boycotting anything receiving funds from said foundation which puts their blogging minions in a stir. Despite the boycott the event did happen and there were some worthy morsels of dialogue though there were no fireworks.
What follows is my transcription of the dialogue. I attempt to type out exactly what was said while inserting some thoughts of my own.
Blakemore was quick to fire some poignant questions beginning with Dr. Fransisco Ayala. He asked "What are your feelings towards religion... are you religious?"
Alaya replied by saying "Whether I am religious or not it is very important for my family. But, for my public image I am not prepared to declare my position on religion."
Ayala chose El Amor Brujo by Manuel de Falla as his musical piece. The image he chose was painted in "a fit of manic energy" in protest by Pablo Picasso. Titled "Guernica" after the town in Spain. Guernica was a spiritual center for the Basques where the Biscayne assembly had historically met under a sacred oak tree. Under command of dictator Francisco Franco, Nazi planes attacked the city of Guernica on April 26, 1937, during the Spanish Civil War. The day of the bombing 1,700 people out of a population of 7,000 were killed. Ayala used this painting to illustrate what science can and cannot do for human understanding. Science can tell us the physical descriptions of what Guernica is. We can know the pigments used, the coordinates of the brush strokes, but this austere description does not tell the story of Guernica. There is no meaning, no purpose in this dry description.
He reasoned that science simply deals with the composition of matter whereas religion gives things purpose and meaning. He described his view as science and religion as two different windows looking into the SAME world. Blakemore reiterated TWO WINDOWS. He neglected to reiterate SAME WORLD. This is a twist on the old NOMA philosophy, or Non-overlapping magisteria approach to the science and religion discussion promoted by prominent evolutionary biologist Stephen Jay Gould. The difference being, in NOMA, science and faith are mutually exclusive. Ayala described his personal academic journey from the study of physics to biology, specifically focusing on human evolution. Though Ayala was not forthcoming with his personal convictions on faith and God he was very clear about his feelings toward creationism. He took the opportunity to slam creationism as a fallacy comparing its teaching in public schools with teaching alchemy and witchcraft.
"There is no place for creationism in science classrooms."
I was glad to see Dr. Ayala take such a strong stance on at least one issue. The fear many non-compatibilist atheists have is the old "give 'em an inch, and they'll take a mile" mentality. Granted, when the lives of children are involved I can see where this fear is warranted. If faith in God is considered higher than any human form of medical help and "faith healing" is given equal merit to proven medical procedures then we have a problem. Watching Ayala put his foot down on creationism gives me hope that reason can rule the day in such instances.
Blakemore then asked "Does science give us hope?"
Ayala answered "I don't think so. Not 'hope' as we understand it in a religious context."
Next Blakemore moved on to Paul Davies who chose "Jupit... Read more »
Newberg A, Pourdehnad M, Alavi A, & d'Aquili EG. (2003) Cerebral blood flow during meditative prayer: preliminary findings and methodological issues. Perceptual and motor skills, 97(2), 625-30. PMID: 14620252
Campbell CS. (2010) What more in the name of god? Theologies and theodicies of faith healing. Kennedy Institute of Ethics journal, 20(1), 1-25. PMID: 20506692
When most people think of evolutionary biology the first thing that comes to mind probably isn't lyrical poetry. However one of the earliest proponents of evolution, none other than Charles Darwin's grandfather Erasmus, presented his vision for the origin of life in the form of an epic poem in 1803. In his critically acclaimed work The Temple of Nature Darwin mused on the natural history of human beings:
Imperious man, who rules the bestial crowd,
Of language, reason, and reflection proud,
With brow erect who scorns this earthly sod,
And styles himself the image of his God;
Arose from rudiments of form and sense,
An embryon point, or microscopic ens!
Now, two hundred years later, the poetic vision of evolution has been updated for the 21st century. In the July issue of Trends in Ecology and Evolution (subscription required), nestled in between their review of A Philosophical View of Biology and an editorial on "Linking the Emergence of Fungal Plant Diseases with Ecological Speciation," biologist Paul Craze reviews what, in all likelihood, is the first review of a hip hop album to ever grace this esteemed journal's pages. Read the rest of this post... | Read the comments on this post...... Read more »
A team of paleoanthropologists report in PLoS One analyzed the skulls of several dozen 11,000 year old Paleoamericans and compared them to the skulls of more than 300 1,000 year old Amerindians. They concluded that based on the morphology, there were two distinct waves of colonizers from Asia. While we know from a couple genetic [...]... Read more »
Hubbe, M., Neves, W., & Harvati, K. (2010) Testing Evolutionary and Dispersion Scenarios for the Settlement of the New World. PLoS ONE, 5(6). DOI: 10.1371/journal.pone.0011105
Dogs are particularly good at tasks that involve communicating or cooperating with humans, which has led some researchers to speculate that they are really good at solving social tasks, more generally. For example, dogs can figure out where a human's attention is, are really good at picking up on eye-gaze and finger pointing cues, distinguish among different individual humans (by contrast, humans are really bad at distinguishing among different individual monkeys, for example), and at least in one outstanding case, are capable of "fast mapping."
Relative to non-human primates, domestic dogs indeed seem to have exceptional social skills. For example, previous research has demonstrated that dogs are able to use human social cues to find hidden food while non-human primates do not. Furthermore, cross-sectional studies of dogs and puppies of different ages, as well as longitudinal studies which track the development of individual puppies, have indicated that dogs do not require extensive exposure to humans to skillfully use those cues (though training enhances their skill). By contrast, wolf pups do require extensive exposure to humans to be able to extract meaning from human social cues such as eye-gaze and finger-pointing. So, while both dogs and wolves are able to understand human social cues, the domestication of dogs seems to have selected for this trait and allowed it to emerge early in development without much experience.
Figure 1: Gratuitous picture of my dog? Sure, why not?
But these studies of social cognition in dogs have had one common theme, which is that they all tested social cognition in the context of a communicative-cooperative task. But do dogs' social skills extend beyond this narrow context? In non-communicative or non-cooperative social tasks, are dogs' social skills otherwise unremarkable? The distinction is not trivial; social information comes in various forms beyond explicit communication. For example, various non-human primate species are known to alter their behavior when trying to steal food from a human, according to whether or not that human is watching them. This is surely a social problem, but one devoid of explicit communication or cooperation.
Two researchers with whom the regular reader of this blog should now be familiar, Victoria Wobber (who ran the bonobo testosterone study I mentioned in the review of Bonobo Handshake) and Brian Hare, wonder to what extent dogs can reason about the social world more broadly. Specifically, would their impressive social skills persist in a task that did not involve cooperative communication? They compared dogs and chimpanzees in two versions of a reversal learning task: non-social and social. Read the rest of this post... | Read the comments on this post...... Read more »
Wobber, V., & Hare, B. (2009) Testing the social dog hypothesis: Are dogs also more skilled than chimpanzees in non-communicative social tasks?. Behavioural Processes, 81(3), 423-428. DOI: 10.1016/j.beproc.2009.04.003
Chimpanzees have culture (or not) depending on your definition.Image: Irish Wildcat / Creative Commons
Author's Note: The following is an expansion on my reply to anthropologist Dan Sperber on the PLoS ONE article "Prestige Affects Cultural Learning in Chimpanzees."
Culture is like art or pornography, it's hard for people to define but everyone knows it when they see it. Cultural anthropologists have long struggled to develop a consistent definition of the very thing that they study, a problem that has resulted in bitter arguments between scholars that, to an outsider, may seem as esoteric as church doctrinal disputes over how many angels can sit upon the point of a needle.
In his 1959 book The Evolution of Culture anthropologist Leslie White famously defined culture as "the extra-somatic means of adaptation for the human organism." His goal was to bring some consistency to a field that had 164 separate definitions of "culture" being used interchangeably in the anthropological literature (which, predictably, made cross-cultural comparisons challenging at best). Today, this view has expanded beyond the human animal and a widely accepted definition is from Peter Richerson and Robert Boyd's celebrated work Not By Genes Alone: How Culture Transformed Human Evolution:
Culture is information capable of affecting individuals' behavior that they acquire from other members of their species through teaching, imitation, and other forms of social transmission.
By information, we mean any kind of mental state, conscious or not, that is
acquired or modified by social learning, and affects behavior.
Earlier I reported on a new study in PLoS ONE by Victoria Horner, Darby Proctor, Kristin E. Bonnie, Andrew Whiten, and Frans de Waal that found chimpanzees will adopt novel behaviors after watching them performed by high-ranking members of their group. The authors concluded that these findings demonstrate "prestige-based cultural transmission" for the first time in nonhuman animals. Their results were consistent with Richerson and Boyd's definition of culture as well as their argument that:
[N]atural selection has shaped the psychology of social learning so that we are predisposed to imitate people with prestige and material well-being. . . [M]any phenomena, ranging from maladaptive fads and fashions to group-functional religious beliefs to symbolically marked boundaries between groups, might result from the properties of prestige bias.
However, French anthropologist Dan Sperber (Research Director at the Jean Nicod Institute, CNRS and 2009 recipient of the Claude Levi-Strauss Prize in Social Science) has recently challenged these findings in chimpanzees and insists that it does not represent cultural transmission at all. In a critique, following from his work in linguistic anthropology, he suggests that humans alone are capable of culture. However, just like in anthropology's past, his conclusions rest on the definition that he prefers to use. Read the rest of this post... | Read the comments on this post...... Read more »
Here is a far-reaching and crucially relevant question for those of us seeking to understand the evolution of culture: Is there any relationship between population size and tool kit diversity or complexity? This question is important because, if met with an affirmative answer, then the emergence of modern human culture may be explained by changes [...]... Read more »
Kline MA, & Boyd R. (2010) Population size predicts technological complexity in Oceania. Proceedings. Biological sciences / The Royal Society. PMID: 20392733
Although some have emphasized the need to breed crops for future climatic conditions, much of the world’s farming population relies on landrace populations, not formal breeding networks.
Undeniable, of course, and a good reason to not forget landraces, or farmers’ local varieties, when thinking about how agriculture will (or will not) adapt to climate change. And [...]... Read more »
Mercer, K., & Perales, H. (2010) Evolutionary response of landraces to climate change in centers of crop diversity. Evolutionary Applications. DOI: 10.1111/j.1752-4571.2010.00137.x
So say Mijares and colleagues (2010), reporting the discovery of a small human third metatarsal from Callao Cave in the northern Philippines. The paper present a brief overview of fieldwork conducted at Callao since 2003 that exposed Pleistocene deposits at the site. The age of the layer in which the metatarsal was recovered was obtained through Electron Spin Resonance (ESR) and Uranium Series (U-Series) on two cervid teeth, one of which yielded an age of 66 +11/-9 kya.From Mijares et al. (2010: 7, Fig. 8, Copyright © 2010 Elsevier Ltd). The Callao specimen (A) is compared to H. sapiens (B) and H. habilis (C), and three non-human primates to the right. The really interesting part of the paper comes when the author discuss the taxonomic attribution of the metatarsal. They compare it to various extant primates and show that it is a convincing Homo bone, aligning itself most closely with small-bodied populations, such as H. habilis or contemporary Philippine Negritos, the latter of which stand out as likely potential analogs of the hominin to whom the metatarsal belonged. That said, "the dimensions of the base of the bone and the section of the shaft are smaller, indicating peculiar proportions for the Callao metatarsal. At the mid-shaft, the shaft appears to be considerably smaller in the dorso-plantar direction than in the Negrito comparative sample. As shown by the reduced dimensions obtained for the dorso-plantar height and medio-lateral breadth of the proximal facet for the lateral cuneiform, the base is very small. It is the smallest of our sample, confirming the particular shape and proportions of the bone as seen from lateral and superior views" (Mijares et al. 2010: 8).The authors emphasize that the peculiarities of the Callao metatarsal are unique in the panorama of known foot bones attributed to various Pleistocene Homo. Provocatively, they point out that the dimensions of the H. floresiensis third metatarsal from Liang Bua (LB 1) are very close to those of the Callao specimen (Mijares et al. 2010: 9). While they present this comparison as speculative, the implications of the exercise are clear: they're asking whether something like H. floresiensis could have been present at Callao ca. 67 kya, although they do cover their bases by emphasizing that the closest analog small-bodied humans known in the region today are Negritos.What's a bit puzzling is their repeated discussion that the Philippines are east of Wallace's line. While I know there's a bit of debate over this, I've always understood the Philippines as being located west of Wallace's line, on the Asian side of things. Mijares et al.'s argument that the Philippines are "beyond Wallace's Line in Island Southeast Asia" appear to be a further manner of potentially linking the Callao specimen to those from Flores.In any case, as the authors conclude, the Callao third metatarsal "documents the presence of a hominin species on the island of Luzon as early as 67 ka, and is testimony to a capability to colonize new territories across open sea gaps. The Philippine specimen also indicates that Flores was not the only island in Wallacea to be occupied by hominins more than 50,000 years ago" (Mijares et al. 2010: 9). Regardless of the precise taxonomic affiliation of that bone, it indicates a great time depth for human presence in that part of the Old World, and provides some thought-provoking evidence that seafaring must have been part of the hominin behavioral range by that time, something that seems to potentially have been the case in other parts of East Asia at that time.Reference:Mijares, A., Détroit, F., Piper, P., Grün, R., Bellwood, P., Aubert, M., Champion, G., Cuevas, N., De Leon, A., & Dizon, E. (2010). New evidence for a 67,000-year-old human presence at Callao Cave, Luzon, Philippines Journal of Human Evolution DOI: 10.1016/j.jhevol.2010.04.008... Read more »
Mijares, A., Détroit, F., Piper, P., Grün, R., Bellwood, P., Aubert, M., Champion, G., Cuevas, N., De Leon, A., & Dizon, E. (2010) New evidence for a 67,000-year-old human presence at Callao Cave, Luzon, Philippines. Journal of Human Evolution. DOI: 10.1016/j.jhevol.2010.04.008
Bonobo Week continues! I'm donating whatever proceeds I receive from my blogging shenanigans for the entire month of June to help the bonobos at Lola Ya Bonobo.
Imagine that you're wandering in the desert and you come across two magic lamps. One lamp grants three wishes. It's your standard sort of magic lamp with a genie in it. (No wishing for extra wishes, of course.) The second magic lamp is, well, a moody magic lamp. It's inconsistent. Sometimes it grants one wish, and sometimes it grants seven wishes. But the thing is, you don't know for sure whether, when you rub the lamp and genie pops out, if he's going to grant you just one or the full seven. But let's make things more interesting. You only get to use one of the lamps. As soon as you rub one of the lamps and the genie comes out, the other lamp disappears. And you might be in the Desert of Infrequent Lamps. Tomorrow you could chance upon two more lamps, with the same rules. But you might not come across any more lamps for many days. So which lamp will you decide to use?
Figure 1: If you're lucky, the genie will have the voice of Robin Williams and will sing to you.
Decades of studies indicated that, as humans, we tend to avoid risk. When it comes to potential gains, we prefer the safe option over the risky option. Most people would choose the sure thing, and summon the three-wish genie, especially since they don't know when they'd be lucky enough to stumble upon their next lamp. Resources (in the shape of magical wish-granting lamps) are scarce. After all, you're wandering through the Desert of Infrequent Lamps. Sucks to be you.
Animals face similar risks on a daily basis, though in the context of things like food acquisition and predator avoidance. So it makes sense that natural selection would, over generations, favor certain cognitive decision-making mechanisms that most effectively addressed those risks. Risk preference patterns in animals are variable though. That variability in risk preference has been observed, at least under experimental conditions, suggests that animals can adjust their strategies given the parameters of the immediate environment. For example, when the riskier option may not be very costly, or when plenty of food is available in the environment, the animal may opt for the riskier choice, and under those circumstances that may actually be the optimal decision.
Read the rest of this post... | Read the comments on this post...... Read more »
Heilbronner, S., Rosati, A., Stevens, J., Hare, B., & Hauser, M. (2008) A fruit in the hand or two in the bush? Divergent risk preferences in chimpanzees and bonobos. Biology Letters, 4(3), 246-249. DOI: 10.1098/rsbl.2008.0081
"Dinah", a young female gorilla kept at the Bronx Zoo in 1914. From the Zoological Society Bulletin.
Frustrated by the failure of gorillas to thrive in captivity, in 1914 the Bronx Zoo's director William Hornaday lamented "There is not the slightest reason to hope that an adult gorilla, either male or female, ever will be seen living in a zoological park or garden." Whereas wild adult gorillas were "savage" and "implacable" beasts which could not be captured (a photo of a sculpture included in Hornaday's article depicts a gorilla strangling one man, brandishing another about with its other arm, and standing on the body of a third), young gorillas were fragile animals that did not last long in the concrete and steel enclosures made for them. One gorilla in Germany had survived for seven years, but the average lifespan of a captive juvenile gorilla was about nine months, and often considerably less than that. This was not to say that zoological parks would stop trying to capture and import young gorillas - Hornaday gave no indication that he wished to stop procuring young gorillas for his zoo - but only that visitors to the Bronx Zoo and other menageries would probably never see an adult gorilla.
Zoos had been failing miserably at keeping apes in captivity for centuries. Most of the animals captured were young individuals which had been snatched from their families or had just been orphaned by specimen collectors. They regularly died on the journey out of Africa or shortly after they arrived at their public confines. Many refused to eat, and most would become sick before passing away, but why this should be so puzzled zoologists. Perhaps, they speculated, it was a matter of climate. The cooler climates of Europe and North America were poor proxies for equatorial Africa, so it was hardly surprising that morality was so high.
Looking back at the practices of zoos during the early 20th century, however, it is apparent that the different climates of Europe and North America cannot solely be blamed for the deaths of these apes. The traditional methods of catching and collecting wild animals which had worked for many other species caused a great deal of stress for captured apes, and the concrete and steel enclosures in which they were placed were cruel by today's standards. (Though, even under today's improved conditions, it can still be questions whether zoos are capable of keeping apes happy and healthy.) Still, in reference to climate, what is curious about the modern disparity between Africa and the places to which the young apes were shipped is that, not so very long ago, much of the northern hemisphere was inhabited by a variety of apes species. North American never had apes, but Europe and much of Asia did, making today's ape species the tattered branches of what once was a richer family tree.
Read the rest of this post... | Read the comments on this post...... Read more »
Merceron, G., Kaiser, T., Kostopoulos, D., & Schulz, E. (2010) Ruminant diets and the Miocene extinction of European great apes. Proceedings of the Royal Society B: Biological Sciences. DOI: 10.1098/rspb.2010.0523
DUNHAM, A., ERHART, E., & WRIGHT, P. (2010) Global climate cycles and cyclones: consequences for rainfall patterns and lemur reproduction in southeastern Madagascar. Global Change Biology. DOI: 10.1111/j.1365-2486.2010.02205.x
How does natural selection account for language? Darwin wrestled with it, Chomsky sidestepped it, and Pinker claimed to solve it. Discerning the evolution of language is therefore a much sought endeavour, with a vast number of explanations emerging that offer a plethora of choice, but little in the way of consensus. This is hardly new, [...]... Read more »
Deacon, T. (2010) Colloquium Paper: A role for relaxed selection in the evolution of the language capacity. Proceedings of the National Academy of Sciences, 107(Supplement_2), 9000-9006. DOI: 10.1073/pnas.0914624107
An unexpected gem from last year's Journal of the American Psychoanalytic Association: Mind over medicine.Surprisingly, it has nothing to do with psychoanalysis. Rutherford and colleagues performed a meta-analysis of lots of clinical trials of antidepressants. Neuroskeptic readers will be all too familiar with these. But they did an interesting thing with the data: they compared the benefits of antidepressants in trials with a placebo condition, vs. trials with no placebo arm, such as trials comparing one drug to another drug.Why do that comparison? Because the placebo effect is likely to be stronger in trials with no placebo condition. If you volunteer for a placebo controlled trial, you'll know that you've got (say) a 50-50 chance of getting inactive sugar pills. You'll probably be uncertain whether or not you'll get better, maybe even quite worried. On the other hand if you're in a trial where you definitely will get a real drug, you can rest assured that you'll feel better - and that in itself might make your depression improve.The paper only presents very preliminary results, but they say that:Our group at Columbia has completed preliminary work involving metaanalyses of randomized controlled trials comparing antidepressant medications to a placebo or active comparator in geriatric outpatients with Major Depressive Disorder (Sneed et al. 2006). In placebo controlled trials, the medication response rate was 48% and the remission rate 33%, compared to a response rate of 62% and remission rate of 43% in the comparator trials (p Notably, they only looked at trials of old age patients, but the same probably applies to everyone else.Why does this matter? The authors suggest one very important implication. There are quite a few trials nowadays comparing the effects of psychotherapy, medication, neither, or both. How it works is that everyone gets pills, 50% of them real drugs and 50% placebos; also, half the people get psychotherapy while the others remain on the waiting list.These trials often find that medication plus psychotherapy is better than just medication alone. This leads to the idea that therapy and drugs should be combined in clinical practice, a message which goes down really well with because it gives both psychopharmacologists and therapists the feeling that they have an important job to do. An example of this kind of trial is the influential TADS from 2004, finding that Prozac and therapy both work in depressed teens, and combining them is best. Everyone's a winner.But as Rutherford et al. point out, there's a problem with this reasoning. The people who only get antidepressants don't know that they're getting any treatment, because they might be getting placebo. But the people who get antidepressants and therapy know that they're getting at least one real treatment (therapy). This is likely to improve their outcome through an expectation effect. (In fact, in TADS, the people on combination treatment were told that they were getting both - they knew they would never get dummy pills - which will have made this even worse.)Now you could say that this doesn't matter: TADS and similar studies show that therapy and medication is better than just medication, and it's purely academic whether that's "just a placebo effect". But the key point is that in real life people always get medication knowing that it's real - so, like the therapy plus medication people in the trials, they get the benefit of knowing that they are getting a real treatment. In the trials the medication-only group don't know that, but in real life they do - so the benefits of adding psychotherapy might be less, or even zero, in real life.The authors of the TADS study did acknowledge this in their original paper, but only very briefly - here's all they say about it:Blinding patients in the placebo and fluoxetine alone groups but not in the CBT alone group (participants knew they would not be receiving fluoxetine) and the fluoxetine combined with CBT group (participants knew that they would be receiving fluoxetine) may have interacted with expectancy effects regarding improvement and acceptability of treatment assignment.Yet this limitation means they, strictly speaking, all TADS showed is that Prozac works in this group. It doesn't prove that adding (very expensive) therapy benefits anyone, in the real world. This is not to say that psychotherapy doesn't work of course, maybe it does, but the point is that therapy + medication trials may be best without a placebo.Rutherford, B., Roose, S., & Sneed, J. (2009). Mind Over Medicine: the Influence of Expectations on Antidepressant Response Journal of the American Psychoanalytic Association, 57 (2), 456-460 DOI: 10.1177/00030651090570020909... Read more »
Rutherford, B., Roose, S., & Sneed, J. (2009) Mind Over Medicine: the Influence of Expectations on Antidepressant Response. Journal of the American Psychoanalytic Association, 57(2), 456-460. DOI: 10.1177/00030651090570020909
One of the issues raised by the recent Sarmiento comments is that of the Miocene apes and the evolution of a short back. All extant apes possess a “short back,” by which we mean a reduction in the lumbar spine combined with an upward elongation of the blades of the pelvis. This back is a nice, [...]... Read more »
McCollum MA, Rosenman BA, Suwa G, Meindl RS, & Lovejoy CO. (2010) The vertebral formula of the last common ancestor of African apes and humans. Journal of experimental zoology. Part B, Molecular and developmental evolution, 314(2), 123-34. PMID: 19688850
Pilbeam, D. (2004) The anthropoid postcranial axial skeleton: Comments on development, variation, and evolution. Journal of Experimental Zoology, 302B(3), 241-267. DOI: 10.1002/jez.b.22
Preuschoft, H., Hayama, S., & Günther, M. (1988) Curvature of the Lumbar Spine as a Consequence of Mechanical Necessities in Japanese Macaques Trained for Bipedalism. Folia Primatologica, 50(1-2), 42-58. DOI: 10.1159/000156333
NAKATSUKASA, M., KUNIMATSU, Y., NAKANO, Y., & ISHIDA, H. (2007) Vertebral morphology of Nacholapithecus kerioi based on KNM-BG 35250. Journal of Human Evolution, 52(4), 347-369. DOI: 10.1016/j.jhevol.2006.08.008
It has been said that "word frequency" is the most important variable in language research, despite the belief by many that it can't be used as a variable because no one really knows what a word is. (see: Minifalsehood: We can't tell what a word is!?!? and A run in my stocking ...)
A recent study in PLoS looks at a heretofore under investigated area, word/character use in Chinese. Read the rest of this post... | Read the comments on this post...... Read more »
Cai, Q., & Brysbaert, M. (2010) SUBTLEX-CH: Chinese Word and Character Frequencies Based on Film Subtitles. PLoS ONE, 5(6). DOI: 10.1371/journal.pone.0010729
As digital and social media infiltrate the world of sports, and make teams, athletes, reporters, and information overall more accessible for fans, there is a greater opportunity for fans to connect to the game. This connection is important to the longevity of the franchises, and has largely been borne on the shoulders of the games' announcers. But why bother turning up the volume on the radio or
... Read more »
Hallett, T. (2003) EMOTIONAL FEEDBACK AND AMPLIFICATION IN SOCIAL INTERACTION. The Sociological Quarterly, 44(4), 705-726. DOI: 10.1111/j.1533-8525.2003.tb00532.x
Like atlatls, but to an even greater degree, bows are rare in the archaeological record because they were made of perishable materials. While some types of atlatls had more durable attachments such as hooks and weights, bows were almost always made of wood and various fibrous materials, except in some areas where they were made [...]... Read more »
Hibben, F. (1938) A Cache of Wooden Bows from the Mogollon Mountains. American Antiquity, 4(1), 36. DOI: 10.2307/275360
I’ve said quite a lot about atlatls, so perhaps it’s time to move on to the second part of this series. The bow and arrow is a sufficiently popular weapon system even today that it doesn’t need much introduction. It’s important to note, however, that most archaeologists have concluded that the bow and arrow is [...]... Read more »
The skull of a spotted hyena (Crocuta crocuta), photographed at the AMNH's "Extreme Mammals" exhibit.
There was something strange about the assemblage of Homo erectus fossils found at Zhoukoudian - the famous 750,000 - 200,000 year old site in China popularly known as Dragon Bone Hill. Despite the abundance of skulls and teeth, there were hardly any remains of the hominins from below the neck. Where were the bodies?
The majority of Homo erectus fossils from Zhoukoudian were discovered and studied by an international team of scientists during the 1920's and 1930's. (Unfortunately most of the specimens were lost with the outbreak of WWII, but casts of these early discoveries remain.) They were just what paleoanthropologists had been hoping to find - evidence that human evolution had primarily taken place in Asia (a hypothesis later overturned by discoveries in Africa) - but the dearth of postcranial remains was puzzling. Clearly something must have happened to bias the fossil record so that skulls were more likely to be preserved than bodies.
At this time many paleoanthropologists believed that, as the English philosopher Thomas Hobbes once put it, the lives of early humans as "nasty, brutish, and short." The heavy brows and robust bones of hominins like Neanderthals and Homo erectus testified of a time when strength and savagery were more important to survival than intelligence or culture. No doubt these prehistoric people were just as brutal to each other as they were to the animals they hunted, and so the horrifying act of cannibalism seemed like a plausible explanation for what the scientists found at Zhoukoudian. Read the rest of this post... | Read the comments on this post...... Read more »
Noel T. Boaz, Russell Ciochon, Xu Qinqi, and Liu Jinyi. (2000) Large Mammalian Carnivores as a Taphonomic Factor in the Bone Accumulation at Zhoukoudian. Acta Anthropologica Sinica, 224-234. info:/
Boaz, N. (2004) Mapping and taphonomic analysis of the Homo erectus loci at Locality 1 Zhoukoudian, China. Journal of Human Evolution, 46(5), 519-549. DOI: 10.1016/j.jhevol.2004.01.007
For those of you familiar with the formal mathematical models of cultural evolution (Cavalli-Sforza & Feldman, 1981; Boyd & Richerson, 1985), you’ll know there is a substantive body of literature behind the process of cultural transmission. It comes as a surprise, then, that experiments in this area are generally lacking. For instance, if we look [...]... Read more »
Mesoudi, A., & Whiten, A. (2008) Review. The multiple roles of cultural transmission experiments in understanding human cultural evolution. Philosophical Transactions of the Royal Society B: Biological Sciences, 363(1509), 3489-3501. DOI: 10.1098/rstb.2008.0129
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