Now, which is more likely:
- That two extremely remote chances came up independently for the same species [rare-squared]; or
- That the one might have something to do with the other?
Monday, November 30, 2009
Tuesday, November 24, 2009
Monday, November 23, 2009
Let us by all means celebrate the man and his achievements. But let us not make him into a demigod, either (nor any scientific hero – if Pasteur discarded 90% of his data, and he did, that doesn’t belittle his contributions to science, and if Mendel made his data fit his model, and he probably didn’t but might have, that doesn’t change one whit the facts of genetics as we now understand them). Darwin did not invent the ball point pen, antibiotics, the iPhone (all hail the Prophet Jobs!), or BLTs, either. What he did is what he did, and more power to him.
What we need to know is that Darwin founded not a theory, or even a set of doctrines, but instead he is the focal point of a series of traditions that converged in his ideas and writings, and which have derived from him. He did not invent biogeography; de Candolle is a good candidate for that. He did not invent natural selection, although he was perhaps the first to think of it as an agent for evolutionary change (excepting Patrick Mathew, who buried his light under a naval architectural bushel). He did not invent genetics (although the term gene comes from his notion of a pangene, and he probably set many people thinking about heredity in a serious manner). He did not give us a mathematical theory; that was William Castle, JBS Haldane, RA Fisher and Sewall Wright, among others to this day.
Friday, November 20, 2009
Thursday, November 19, 2009
Monday, November 16, 2009
Thursday, November 12, 2009
Two tiny changes in the sequence of one gene could have helped install the mechanisms of speech and language in humans.
In 2001, a gene called FOXP2 was found to underlie a rare inherited speech and language disorder1. It encodes a transcription factor called FOXP2, a protein 'dimmer-switch' that binds to DNA and helps to determine to what extent other genes are expressed as proteins.
Experiments have now revealed that the human version of FOXP2, which has two different amino acids compared with the version carried by chimps, has differing effects on genes in the brains of the two species. These differences could affect how the brain develops, and so explain why only humans are capable of language.
But one fraud outstripped them all, eclipsing the others with its sheer audacity. Between 2000 and 2002, Jan Hendrik Schön, a researcher at Bell Laboratories, published more than 20 articles on electrical properties of unusual materials. He shot to the very top of the booming field of “molecular electronics”—a wonder field in which researchers aim to shrink computer chips down to single-molecule components. At Schön’s peak, he was submitting 4 or 5 articles per month, most of them going to top journals like Science and Nature. He hit his record in autumn 2001, turning out 7 articles that November alone. The output was staggering. It’s rare for a scientist—even a string theorist, beholden neither to instruments nor to data—to submit 7 articles in an entire year, let alone one month. And Schön’s papers were no run-of-the-mill exercises. In them, he announced one unbelievable discovery after another: He had created organic plastics that became superconductors or lasers; he had fashioned nanoscale transistors; and more. The editors of Science hailed one of his many contributions as a “breakthrough of the year” in 2001. The CEO of Lucent Technologies (parent company of Bell Labs) likewise touted Schön’s work when courting investors. Everything Schön touched seemed to turn to research gold.
Wednesday, November 11, 2009
Monday, November 09, 2009
The newest issue of Science Magazine includes a lovely demonstration of multilevel selection by Omar Tonsi Eldakar, my former graduate student, who is currently at the University of Arizona's Center for Insect Science.
Readers who have been following my "Truth and Reconciliation for Group Selection" series will be well prepared to appreciate the import of the Science article. Group selection requires variation among groups. Variation among groups is eroded by dispersal. Therefore, group selection can only take place in groups that are highly isolated from each other. That is part of the reasoning the led to the conclusion that group selection can only take place under highly restrictive conditions.
But wait. This argument assumes that dispersal is random. What if dispersal is conditional? What if individuals stay in groups when they are sufficiently cooperative but leave when they become overrun by selfish individuals? In this case, dispersal might increase variation among groups, improving the conditions for group selection. John Pepper and Athena Aktipis (featured in T&R XII) are two theorists who have studied this "walk away" process in agent-based simulation models.'