HENRY

Assorted interesting posts for nice lazy Sunday:

1. John Hawks provides the best discussion of the recent identification of the FoxP2 gene in Neanderthals without any of the stupid journalistic hype that others have succumbed to (although he does use the term “neandercooties”). Go read his The amazing talking Neandertals.
2. Creek Running North has identified that
   Evolutionary Psychology may be genetically hardwired…

   Biologists have long assumed that evolutionary psychology, a controversial branch of psychology that ascribes many common social behaviors to genetics, is a muddled blend of half-understood evolutionary biology, selective data mining and resentment of women’s changing roles in society.

   A new study, published in today’s issue of the German publication Unwirklichen Genetikjournal, does not challenge that assessment. But it does suggest that some men may be genetically predisposed to believe in evolutionary psychology, a finding that may well suggest future methods of treatment of the psychological malady.

3. Scientist debunks nomadic Aborigine ‘myth’:
   

   Before white settlers arrived, Australia’s indigenous peoples lived in houses and villages, and used surprisingly sophisticated architecture and design methods to build their shelters, new research has found.

4. More ammunition inn the punctuated evolution debate, this time it’s Punctuated genome size evolution in Liliaceae:
   

   Most angiosperms possess small genomes (mode 1C = 0.6 pg, median 1C = 2.9 pg). Those with truly enormous genomes (i.e. ≥ 35 pg) are phylogenetically restricted to a few families and include Liliaceae – with species possessing some of the largest genomes so far reported for any plant as well as including species with much smaller genomes. To gain insights into when and where genome size expansion took place during the evolution of Liliaceae and the mode and tempo of this change, data for 78 species were superimposed onto a phylogenetic tree and analysed. Results suggest that genome size in Liliaceae followed a punctuated rather than gradual mode of evolution and that most of the diversification evolved recently rather than early in the evolution of the family.

5. The Evolutionary Origins of Human Patience: Temporal Preferences in Chimpanzees, Bonobos, and Human Adults:
   

   To make adaptive choices, individuals must sometimes exhibit patience, forgoing immediate benefits to acquire more valuable future rewards. Although humans account for future consequences when making temporal decisions, many animal species wait only a few seconds for delayed benefits. Current research thus suggests a phylogenetic gap between patient humans and impulsive, present-oriented animals, a distinction with implications for our understanding of economic decision making and the origins of human cooperation.

   On the basis of a series of experimental results, we reject this conclusion. First, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes) exhibit a degree of patience not seen in other animals tested thus far. Second, humans are less willing to wait for food rewards than are chimpanzees. Third, humans are more willing to wait for monetary rewards than for food, and show the highest degree of patience only in response to decisions about money involving low opportunity costs.

   These findings suggest that core components of the capacity for future-oriented decisions evolved before the human lineage diverged from apes. Moreover, the different levels of patience that humans exhibit might be driven by fundamental differences in the mechanisms representing biological versus abstract rewards.

6. Finally, there’s a fun review and historical perspective of neutral theory in the latest Journal of Evolutionary biology:

   To resolve a panselectionist paradox, the population geneticist Kimura invented a neutral theory, where each gene is equally likely to enter the next generation whatever its allelic type. To learn what could be explained without invoking Darwinian adaptive divergence, Hubbell devised a similar neutral theory for forest ecology, assuming each tree is equally likely to reproduce whatever its species. In both theories, some predictions worked; neither theory proved universally true.

   Simple assumptions allow neutral theorists to treat many subjects still immune to more realistic theory. Ecologists exploit far fewer of these possibilities than population geneticists, focussing instead on species abundance distributions, where their predictions work best, but most closely match non-neutral predictions.

   Neutral theory cannot explain adaptive divergence or ecosystem function, which ecologists must understand. By addressing new topics and predicting changes in time, however, ecological neutral theory can provide probing null hypotheses and stimulate more realistic theory.

Posted on October 20th, 2007 by Simon Greenhill