Adaptation

Gene Expression

Tag archives for Adaptation

X chromosome marks the spot, again

A few days ago I discussed a new paper which explores the patterns of natural selection in the genome of the X chromosome. As you know the X is “carried” disproportionately by females, as males have only one copy, so it offers up an interesting window into evolutionary dynamics (see The Red Queen for a…

Rice, alcohol and genes

Changes in human diet driven by cultural evolution seem to be at the root of many relatively recently emerged patterns of genetic variation. In particular, lactase persistence and varied production of amylase are two well known cases. Both of these new evolutionary genetic developments are responses to the shift toward carbohydrates over the last 10,000…

Fungus adapts fast…at first

The Properties of Adaptive Walks in Evolving Populations of Fungus: The rarity of beneficial mutations has frustrated efforts to develop a quantitative theory of adaptation. Recent models of adaptive walks, the sequential substitution of beneficial mutations by selection, make two compelling predictions: adaptive walks should be short, and fitness increases should become exponentially smaller as…

The downside of beauty

Well, I don’t quite know about that, but that’s the sort of take-away from a new paper in PLoS Biology which looks at the downsides of female attractiveness. A Cost of Sexual Attractiveness to High-Fitness Females: Adaptive mate choice by females is an important component of sexual selection in many species. The evolutionary consequences of…

A few months ago I reviewed a paper which examined the various complexities of interpreting signals of natural selection from recently developed genomic tests in response to the avalanche of human sequence data. In the paper, Signals of recent positive selection in a worldwide sample of human populations, the authors state: We find that putatively…

400-500 years ago in the midst of the Great Dying somewhere the indigenous inhabitants of the New World suffered mortality rates on the order of 90-95%. This was almost certainly due to the facts of evolutionary history; the indigenous peoples had little defense against Eurasian pathogens. A result has been the reality that most of…