Tag Archives: natural selection

A combination of living and nonliving selective forces drive local adaptation across species

Posted on March 20, 2020 by Amy McDermott

Both living and nonliving factors can interact to shape local adaptation, according to a recent study in The American Naturalist. The metaanalysis also entailed the use of a method, borrowed from the social and medical sciences, that identified common themes and research gaps … Continue reading →

Molecular evidence supports Darwin’s adaptationist view, informing the debate over what drives evolution

Posted on February 28, 2020 by Amy McDermott

Myriad genetic differences distinguish the genomes of two species. What fraction of those differences arises by positive natural selection versus random genetic drift is a central question and topic of debate in evolutionary biology. A recent study in Nature Ecology … Continue reading →

Categories: Evolution | Genetics | Tagged adaptation, natural selection, negative selection, neutral theory of evolution, positive selection | Leave a comment

By separating life stages, metamorphosis may circumvent harmful evolutionary tradeoffs

Posted on July 30, 2019 by Jessica P. Johnson

There’s no guarantee evolution will bestow the best version of every trait. The benefits of one trait may impose a cost when an unfavorable trait, correlated genetically, comes along for the ride. In a recent study on wood frogs (Rana sylvatica) … Continue reading →

Journal Club: A new take on why tumors develop drug resistance

Posted on June 26, 2015 by Charles Choi

Cancer’s notorious resistance to therapy is often explained as the result of natural selection of newly mutating cells. Cancer-killing drugs wipe out nearly all of a tumor’s cells, but random mutations may allow for drug resistance in some cells, and … Continue reading →

Journal Club: Newly found mutation contributes to irregular chromosome number, a major cause of pregnancy loss

Posted on May 7, 2015 by Charles Choi

When a baby does not make it to term, an irregular number of chromosomes in the embryo is often the root cause. The phenomenon, known as aneuploidy, is surprisingly common: it can be detected in roughly three-quarters of human embryos … Continue reading →