Evolutionary Dynamics

Nice to see an excellent science writer, Carl Zimmer, write about an excellent mathematical biologist, Martin Nowak, in an article in the New York Times (via The Loom).

Here is a non-technical lecture on evolutionary dynamics by Martin Nowak.

I also look forward to reading his most recent book, Evolutionary Dynamics: Exploring the Equations of Life.

Harvard’s Program for Evolutionary Dynamics was established by Harvard’s then President Larry Summers as a way of using the theory of evolution as a common foundation for biology and economics (I am not sure that he took the other social sciences seriously). Judging from the website, the program’s current mission is now somewhat less ambitious. 


Bernd Heinrich’s new book

On Radio Open Source, Christopher Lydon interviews Bernd Heinrich. This is one interview that didn’t work. Christopher Lydon is all over the place, and he comes across as someone with a serious attention deficit problem. However, after listening to the interview, one thing is clear in my mind. I want to read Heinrich’s new book, The Snoring Bird: My Family’s Journey Through a Century of Biology.

I have previously read his Why We Run: A Natural History. It was excellent.

What we need now is an interview with Bernd Heinrich without so many interruptions, e.g. following the format on BBC’s The Interview.

Natural-born runners

Several blogs have linked to this article about Daniel Liberman’s argument that about 2 million years ago our ancestors evolved physical characteristics that have no impact on walking, but make humans better endurance runners, presumably because of a shift in food consumption from scavenging to hunting.

Speaking about running, if you are a runner, 2PEAK is the best web-based training program I have seen. It dynamically adjusts your training program, and you can upload data from Garmin, Polar, and Suunto watches. It is, however, somewhat pricey.

Here is what Owen learned from running the London Marathon.

The Quartenary Conundrum

The Quartenary Conundrum is this: While current empirical and theoretical ecological forecasts suggest that many species could be at risk from global warming, during the recent ice ages surprisingly few species became extinct.

In a recent paper in BioScience, Forecasting the Effects of Global Warming on Biodiversity (pdf), Daniel Botkin et al. state that

Fossil evidence and recent ecological and genetic research, along with specific problems with present forecasting methods, lead us to believe that current projections of extinction rates are overestimates. Previous work has failed to adequately take into account mechanisms of persistence. […]

Until recently, it was thought that past temperature changes were no more rapid than 1 degree Celsius (°C) per millennium, but recent information from both Greenland and Antarctica, which goes back approximately 400,000 years, indicates that there have been many intervals of very rapid temperature change, as judged by shifts in oxygen isotope ratios. Some of the most dramatic changes (e.g., 7°C to 12°C within approximately 50 years; Macdougall 2006) are actually of greater amplitude than anything projected for the immediate future. […]

What, then, is the answer to the Quaternary conundrum? The answer appears to lie in part with the ability of species to survive in local “cryptic” refugia, that is, to exist in a patchy, disturbed environment whose complexity allows faster migration than forecast for a continuous landscape, within which species move only at a single rate. The answer also lies in part with greater genetic heterogeneity within species, including local adaptations,which allows rapid evolution. For example, populations close to latitudinal borders are likely to be better adapted to some environmental changes than the average genotype. However, the conundrum is not completely solved, and some important genetic research suggests that species are more vulnerable than the fossil record indicates. A fuller solution to the conundrum will be important for improving forecasts of climate change effects on biodiversity.

HT Carl Zimmer.

Note that this is not a call for complacency, it is a call for better models of climate change effects on extinctions.

Accelerating human evolution

The concept of the EEA, the Environment of Evolutionary Adaptedness, never made much sense. In its strong form it is based on the misunderstanding that we evolved during the Stone Age, and then we more or less stopped evolving.

World Science reports on a study by Greg Cochran and John Hawks,

The tra­di­tion­al pic­ture of hu­mans as a fi­n­ished prod­uct be­gan to erode in re­cent years, sci­en­t­ists said, with a crop of stud­ies sug­gesting our ev­o­lu­tion in­deed goes on. But the new­est in­vest­i­ga­tion goes fur­ther. It claims the pro­cess has ac­tu­al­ly ac­cel­er­at­ed.

It al­so down­plays the im­por­tance of a much-scru­ti­nized era around 200,000 years ago, when hu­mans con­sid­ered “ana­tom­i­cally mod­ern” first ap­pear in the fos­sil rec­ord. In the stu­dy, this ep­och e­merges as just part of a vast arc of ac­cel­e­rat­ing change.

“The or­i­gin of mod­ern hu­mans was a mi­nor event com­pared to more re­cent ev­o­lu­tion­ary chang­es,” wrote the au­thors of the re­search, in a pre­sent­a­tion slated for Fri­day in Phi­l­a­del­phia at the an­nu­al meet­ing of the Amer­i­can As­so­ci­a­tion of Phys­i­cal An­th­ro­po­l­o­g­ists. [...]

Hawks and Coch­ran said some of the most no­ta­ble phys­i­cal changes in hu­mans have been ones af­fect­ing the size of the brain case.

A “thing that should prob­a­bly wor­ry peo­ple is that brains have been get­ting smaller for 20,000 to 30,000 years,” said Coch­ran. But brain size and in­tel­li­gence aren’t tightly linked, he added. Also, growth in more ad­vanced brain ar­eas might have made up for the shrinkage, Coch­ran said; he spec­u­lated that an al­most break­neck ev­o­lu­tion of high­er fore­heads in some peo­ples may re­flect this. A study in the Jan. 14 Brit­ish Den­tal Jour­nal found such a trend vis­i­ble in Eng­land in just the past mil­len­ni­um, he noted, a mere eye­blink in ev­o­lu­tionary time.

Research pub­lished in the Sept. 9, 2005 is­sue of the re­search jour­nal Sci­ence by Lahn and col­leagues found that two genes linked to brain size are rap­idly evolv­ing in hu­mans.

Harpending on McKinnon on Evolutionary Psychology

Henry Harpending reviews Susan McKinnon’s book Neo-Liberal Genetics,

…She does not complain that evolutionary psychology is bad science according to standard criteria for evaluating science: Instead she dislikes the “rhetorical structures and strategies of the texts.” She deplores the “narrative” of evolutionary psychology because it “severely constricts the kinds of questions we can ask and the kinds of social worlds we can possibly imagine and endeavor to create for ourselves” (p. 152). In other words McKinnon dislikes the implied constraints on her political fantasies.

Everyone understands and deals with evolutionary psychology. We understand why our cat was easier to toilet train than our baby was: One has the brain of a denning predator and the other of a mobile and occasionally arboreal ape. We also understand that there is no “should” implied in this: No one thinks that children should not be toilet trained. MacKinnon, by contrast, attributes to evolutionary psychologists the belief that saying something “is” is the same as saying that that it “ought” to be. Here, for example, is her notion of what genetic individualism means: “that the ‘public good’ should be replaced by individual responsibility and social services privatized; that profit and capital should be maximized through the deregulation of markets – that is, that competition should run its course unchecked – in a ‘race to the bottom’ – regardless of the social consequences” (p. 44). Notice the “shoulds”, none of which are appropriate…

Despite an occasional interesting insight, most of this book reads like a clone of the dreadful wrong-headed ramblings that were the “sociobiology debate” of the 1970s.

Bob Trivers gets the Crafoord Prize in Biosciences

We are a bit late, but here is the announcement from the Royal Swedish Academy of Sciences,

… Robert Trivers, is one of the small group of pioneering scientists who began to ponder on the social behaviour patterns of animals and how they might have arisen through evolution. Between 1971 and 1976, he launched five ideas that have been of the greatest importance for the development of sociobiology. They have inspired many behavioural ecologists, who have to a large extent confirmed Trivers’s ideas.

Continue reading