Evolution imprisoned in biology classrooms

David Sloan Wilson is an evolutionary biologist who teaches in the Department of Anthropology at Biology Binghamton University. He has long been a champion of multi-level selection theory, and he boldly applied his research and findings to human conduct, boldly going where many biologists hesitate to go, based upon a well-documented history of derision aimed at scientists who dare to study human beings as though they were animals subject to natural selection. This, despite the fact that humans clearly are animals that are subject to the forces of natural selection. Today, I spotted an excellent video of an October 30, 2009 talk that David Sloan Wilson gave following the publication of his book, "Evolution for Everyone." The video lasts almost one hour. I previously posted extensively on his book here. I've posted on other aspects of his work here and here . Wilson opens his clear, insightful, sometimes blunt and oftentimes humorous talk by announcing that higher education has an "evolution problem." The problem is that many in academia resist applying modern scientific biological findings to their own disciplines, even though these biological findings would be highly relevant. Wilson thus refers to the Ivory Tower as the "Ivory Archipelago." Darwin anticipated the broad scope of his theory, but many teachers in the humanities refuse to have anything to do with well-substantiated principles of biology, even modern findings would be highly informative to their fields of study. [More . . . ]

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The human edge: our ideas have sex

In the Wall Street Journal, Matt Ridley argues that human beings haven't flourished because of anything we do individually. Rather, it is our ability to share and to building upon previous ideas of others--it is our "collective intelligence":

The notion that exchange stimulated innovation by bringing together different ideas has a close parallel in biological evolution. The Darwinian process by which creatures change depends crucially on sexual reproduction, which brings together mutations from different lineages. Without sex, the best mutations defeat the second best, which then get lost to posterity. With sex, they come together and join the same team. So sex makes evolution a collective and cumulative process in which any individual can draw on the gene pool of the whole species. And when it comes to gene pools, the species with gene lakes generally do better than the ones with gene ponds—hence the vulnerability of island species to competition with continental ones.

It is precisely the same in cultural evolution. Trade is to culture as sex is to biology. Exchange makes cultural change collective and cumulative. It becomes possible to draw upon inventions made throughout society, not just in your neighborhood. The rate of cultural and economic progress depends on the rate at which ideas are having sex. . . . So here is the answer to the puzzle of human takeoff. It was caused by the invention of a collective brain itself made possible by the invention of exchange. . . . Prosperity consists of getting more and more narrow in what you make and more and more diverse in what you buy. Self-sufficiency—subsistence—is poverty.

Ridley concludes that this inexorable building upon prior ideas by sharing them is ultimately a "cheery" one (he points to reduced child mortality and increased per capita income worldwide), despite the occasional setbacks.

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Your Neandertal Ancestors

Scientific convention used to be that modern humans came out of Africa and completely replaced Neandertals (also spelled "Neanderthals") without interbreeding (for example, see here). New evidence suggests that this hypothesis is incorrect, according to an article by Ann Gibbons called "Close Encounters of the Prehistoric Kind." The article appears in the May 7, 2010 edition of Science (available online only to subscribers). An international team has now completed the draft sequence of the Neandertal genome, which includes more than 3 billion nucleotides collected from the bones of three female Neandertals who lived in Croatia more than 38,000 years ago." The analysis described was astoundingly complex, and the consequences of this analysis are startling:

By comparing this composite Neandertal genome with the complete genomes of five living humans from different parts of the world, researchers found that both Europeans and Asians share 1% to 4% of their nuclear DNA with Neandertals. But Africans do not. This suggests that early modern humans interbred with Neandertals after moderns left Africa, but before they spread into Asia and Europe. The evidence showing interbreeding is "incontrovertible," says paleoanthropologist John Hawks of the University of Wisconsin, Madison, who was not involved in the work. "There's no other way you can explain this."

Therefore, many people living outside of Africa carry "a small but significant amount of DNA from these extinct humans." The consequences of this amazing finding are not lost on anyone:

In a sense, the Neandertals are then not altogether extinct, says lead author Svante Paabo, a paleogeneticist at the Max Planck Institute for evolutionary anthropology in Leipzig Germany, who is surprised to find out he was part Neanderthal. "They live on in some of us."

The Science article presents the following list of things we now know about Neanderthals:
  • The genomes of modern humans and Neanderthals are 99.84% identical.
  • The scientific data don't support interbreeding when scientists had most expected it (between 45,000 and 30,000 years ago in Europe).
  • Neanderthals coexisted with modern humans in Europe from 30,000 to 45,000 years ago, and perhaps in the Middle East as early as 80,000 years ago.
  • The amount of admixture is tiny, even among Europeans and Asians, but Neanderthals "are significantly more closely related to non-Africans than Africans on average.
  • The new data fits with the discovery of fossils and stone tools from Israel caves about 80,000 years ago (modern humans and Neanderthals both used these caves and had much in common--they used similar tool-kits and under the same animals). One Neandertal skeleton from the Middle East looked "less robust than Neanderthals in Asia and Europe.
  • Despite the ability to sequence some Neanderthal DNA, there is no possibility of cloning a Neanderthal.
  • "The isolated DNA was in pieces typically about 50 bases long, and there were many missing stretches. Further, despite the story one often hears in the mass media, DNA is not completely responsible for the appearance of an animal. "Chemical modifications to the genome, the way chromosomes arrange in the nucleus, and maternal components in the egg all play a role in translating a genetic blueprint into a viable individual." None of these are available with regard to Neanderthals. As soon as you substitute another oocyte (e.g., that of a modern human) for that of a Neandertal, you would change the resulting organism.
Despite the fact that there was some interbreeding, it did not happen much. This article quotes evolutionary geneticist Sarah Tishkoff, who asked "Was it a cultural barrier?" We are cousins with every living thing on planet Earth (including trees and see here), but many of us are both cousins and descendants of Neandertals. Therefore, for those of you who have had ancestors from anywhere outside of Africa (keeping in mind that all of us have ancestors from Africa), you are African and you are Neandertal. I'm planning on having a bit of fun the next time a bureaucratic form requires me to designate my "race."

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How are Humans Better?

A new comment thread on an old post discusses the precept that humans are somehow "better" than all other creatures. Sure, as a member of our team, I'd like to think that we are Number One. We've even written books attributed to deities that prove that we are the reason for creation, that the octillions of stars in the universe were all put there just for our amusement. Therefore, the book and its believers maintain, we must be the best thing ever. But as an educated human raised by scientists to find first sources and question suppositions, I wonder: "How are we better?" I have posted before on some of the ways in which our Creator (to use that paradigm) has short changed us. Name any characteristic of which we are proud, and it is easy to find another creature that exceeds our ability. I can only think of one exception: Communicating in persistent symbols. Unlike cetaceans, birds, fellow primates, and others who communicate fairly precisely with sounds, gestures, or chemical signals, we can detach communication from ourselves and transport or even delay it via layers of uncomprehending media (paper, wires, illiterate couriers, etc). We can create physical objects that abstract ideas from one individual and allow the idea to be absorbed by another individual at a later time. It also allows widely separated groups to share a single culture, at least in part. This learned behavior is based on our apparently unique ability to abstract in multiple layers and to abstract to a time well beyond the immediate future. We can take an idea to a series of sounds to a series of static symbols, and back again. Our relatively modern ability to reason abstractly (math, science) evolved from our ability to abstract communications. Even Einstein couldn't hold the proof of E=MC2 in his head. But is this unique ability really sufficient to declare ourselves overall inherently "better"?

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