All Articles Tagged As: natural selection

Natural selection may not produce the best organisms (7/20/2008)

A team of researchers has developed a new theory, which suggests that life may not always be optimal, at least in the long run. ...> Full Article

Probing Question: Why are flowers beautiful? (1/28/2008)

Biologist studies the genetic roots of flowers ...> Full Article

Genome scientists discover that evolution sometimes 'reinvents the wheel' (1/24/2008)

If a particular biological innovation is good enough to evolve once, it may sometimes be good enough to evolve multiple times independently in different species. ...> Full Article

Study discovers secret of Scottish sheep evolution (1/21/2008)

Researchers from the University of Sheffield, as part of an international team, have discovered the secret of why dark sheep on a remote Scottish Island are mysteriously declining, seemingly contradicting Darwin's evolutionary theory. ...> Full Article

Gene neighbors may have taken turns battling retroviruses (12/22/2007)

A cluster of antiviral genes in humans has likely battled retroviral invasions for millions of years. New research by Sara Sawyer, Ph.D., a postdoctoral research fellow in the Basic Sciences Division at Fred Hutchinson Cancer Center, now finds that in addition to the previously identified TRIM5 gene that can defend against retroviruses like HIV, a related gene right next door, called TRIM22, may have participated in antiviral defense. ...> Full Article

Why Sex Chromosomes Evolve So Rapidly (10/24/2007)

In animals with separate sexes, embryos commit to becoming male or female at an early stage. Often this key decision is made by sex determination genes on the sex chromosomes. The genes involved in sexual development have changed remarkably little during evolution. In contrast, the sex determination genes and the sex chromosomes themselves are among the most rapidly changing features of the genome. ...> Full Article

A gene divided reveals details of natural selection (10/11/2007)

In a molecular tour de force, researchers have provided an exquisitely detailed picture of natural selection as it occurs at the genetic level. ...> Full Article

Researchers devise way to calculate rates of evolution (10/5/2007)

"Survival of the fittest" has popularly described evolution for more than a century, but a new study published in the Royal Society journal Biology Letters provides further evidence that random genetic mutations over millions of years may also play a powerful role. ...> Full Article

Three-way mating game of North American lizard found in distant European relative (10/2/2007)

An intricate three-way mating struggle first observed in a species of North American lizard has been discovered in a distant relative, the European common lizard. The two species are separated by 5,000 miles and 175 million years of evolution, yet they share behavioral and reproductive details right down to the gaudy colors of the males. ...> Full Article

Selection on genes underlying schizophrenia during human evolution (9/6/2007)

Several genes with strong associations to schizophrenia have evolved rapidly due to selection during human evolution, according to new research in the Proceedings of the Royal Society B. ...> Full Article

Male Deer Are Born To Live Fast, Die Young (9/3/2007)

In the September issue of The American Naturalist, Juan Carranza (Biology and Ethology Unit, University of Extremadura, Spain) and Javier Pérez-Barbería (Macaulay Institute, United Kingdom) offer a new explanation for why males of ungulate species subjected to intense competition are born with lower survival expectancies than females. ...> Full Article

Bacteria Mutate Much More Than Previously Thought (8/20/2007)

Portuguese scientists show that in bacteria the rate of beneficial mutations – those that increase the capacity of an organism to survive in a particular environment – is much higher than previously thought. ...> Full Article

Researchers Witness Natural Selection At Work In Dramatic Comeback Of Male Butterflies (7/16/2007)

An international team of researchers has documented a remarkable example of natural selection in a tropical butterfly species that fought back - genetically speaking - against a highly invasive, male-killing bacteria. ...> Full Article

Scientists Propose The Kind Of Chemistry That Led To Life (6/13/2007)

Before life emerged on earth, either a primitive kind of metabolism or an RNA-like duplicating machinery must have set the stage - so experts believe. But what preceded these pre-life steps? ...> Full Article

Why Are There So Many More Species Of Insects? Because Insects Have Been Here Longer (4/8/2007)

J. B. S. Haldane once famously quipped that "God is inordinately fond of beetles." Results of a study by Mark A. McPeek of Dartmouth College and Jonathan M. Brown of Grinnell College suggest that this fondness was expressed not by making so many, but rather by allowing them to persist for so long. ...> Full Article

Carrying Heavy Objects Caused Humans to Evolve Upright Posture (4/6/2007)

The next time you are struggling to carry your bags home from the supermarket just remember that this could, in fact, be the reason you are able to walk upright on two legs at all! How we have evolved to walk on two legs remains a fundamental but, as yet, unresolved question for scientists. A popular explanation is that it is our ability to carry objects, particularly children, which forced early hominins onto two legs. ...> Full Article

'Selfish DNA' driving insecticide resistance (4/2/2007)

Transposable elements, sometimes called ‘selfish DNA’, can be responsible for insecticide resistance, according to scientists from the Universities of Exeter, Bath and Melbourne. Transposable elements (TEs) can ‘jump around’ the genome and cause mutations by inserting into the coding regions of genes and disrupting or altering, and in this case increasing, gene function. ...> Full Article