natural selection tagged posts

These illustrations represent different levels of adaptive complexity we might imagine when thinking about aliens. (a) A simple replicating molecule, with no apparent design. This may or may not undergo natural selection. (b) An incredibly simple, cell-like entity. Even something this simple has sufficient contrivance of parts that it must undergo natural selection. (c) An alien with many intricate parts working together is likely to have undergone major transitions. Credit: Helen S. Cooper

What evolutionary biology tells us about how aliens could look. For the first time, researchers show how evolutionary theory can be used to support alien predictions and better understand their behavior...

dsx genomic structure and RNAi phenotypes.

1st-of-its-kind study helps answer major question about development and evolution in males versus females. New details about the behavior of the gene called “doublesex,” or dsx have been found. ” How do animals with similar genomes – such as males and females of the same species – produce different versions of the same trait? And why do some traits, like ornamental features that attract mates, vary so widely, while others, like legs, don’t?” said Cris Ledón-Rettig, a postdoctoral researcher in the IU Bloomington College of Arts and Sciences’ Department of Biology, who led the study.

The study is significant because it’s the first to look at the effect of dsx across the whole genome...

John Tower and his colleagues found that treating flies with a steroid hormone decreased egg production in females while increasing longevity. Credit: USC Photo/Gus Ruelas

Research in flies, mice supports theory that sexes age differently. What helps her live longer might be harmful to him, according to a new study that may shed light on how and why organisms age. Analyzing years of previous research on dietary and pharmaceutical tests on flies and mice, researchers showed that aging interventions can have opposite effects on mortality rates in males versus females. The findings appear consistent with data gathered on humans as well, says John Tower of the USC Dornsife College of Letters, Arts and Sciences and the USC Davis School of Gerontology.

Treating flies with steroid hormone mifespr...