Latest Evolutionary biology Stories

Creatures should help each other in different ways in tight times versus times of plenty Not all acts of altruism are alike, says a new study. From bees and wasps that die defending their nests, to elephants that cooperate to care for young, a new mathematical model pinpoints the environmental conditions that favor one form of altruism over another. The model predicts that creatures will help each other in different ways depending on whether key resources such as food and habitat are...

New evidence proves humans are continuing to evolve and that significant natural and sexual selection is still taking place in our species in the modern world. Despite advancements in medicine and technology, as well as an increased prevalence of monogamy, research reveals humans are continuing to evolve just like other species. Scientists in an international collaboration, which includes the University of Sheffield, analyzed church records of about 6,000 Finnish people born between...

Male praying mantises are more likely to engage in risky mating behavior if they have not had recent access to females, as reported Apr. 25 in the open access journal PLoS ONE. Female praying mantises are known for their cannibalistic behavior toward their mates, and males take a large risk when they attempt to reproduce. In the current work, led by William Brown of State University of New York at Fredonia, the researchers found that males modulate this risk by altering their approach rate...

Bacteria evolved way to safeguard crucial genetic material Just as banks store away only the most valuable possessions in the most secure safes, cells prioritize which genes they guard most closely, researchers at the European Molecular Biology Laboratory’s European Bioinformatics Institute (EMBL-EBI) have found. The study, published online today in Nature, shows that bacteria have evolved a mechanism that protects important genes from random mutation, effectively reducing the risk of...

Evolutionary biologists at the University of Toronto have found that individuals with low-quality genes may produce offspring with even more inferior chromosomes, possibly leading to the extinction of certain species over generations. A study published in Proceedings of the National Academy of Sciences (PNAS) predicts that organisms with such genetic deficiencies could experience an increased number of mutations in their DNA, relative to individuals with high-quality genes. The research...

Caltech researchers say habitat loss and tropical cooling were to blame for mass extinction The second-largest mass extinction in Earth's history coincided with a short but intense ice age during which enormous glaciers grew and sea levels dropped. Although it has long been agreed that the so-called Late Ordovician mass extinction—which occurred about 450 million years ago—was related to climate change, exactly how the climate change produced the extinction has not been known. Now, a...

Courtship rituals can be all-consuming, demanding time and effort – but now scientists have discovered why it might be worth it Courtship rituals can be all-consuming, demanding time and effort – but now scientists have discovered why it might be worth it. Attracting a mate – which can take significant effort, such as in a peacock's show of feathers or the exhaustive rutting of stags – can produce benefits for a species in the long term, a study suggests. Scientists have...

Genetic mutations in cancer cells can lead to resistance to treatment, thereby potentially resulting in relapse. However, a new article, published April 3 in the magazine section of the online, open-access journal PLoS Biology, suggests that the converse may also happen. Steven Frank from the University of California, Irvine, and Marsha Rosner from the University of Chicago, propose that it may often be the case that a few cells become resistant before any genetic change, and then later...

A second mutation found in the tumors of patients with BRAF-mutated metastatic melanoma does not contribute to resistance to BRAF inhibitor drugs, a finding that runs counter to what scientists expected to be true. The study by researchers at UCLA's Jonsson Comprehensive Cancer Center found that patients with the mutations in both the MEK1 and BRAF genes respond as well to the inhibitors as patients with the BRAF mutation alone. Another surprising finding is that the MEK1 and BRAF...

From miniature elephants to monster mice, and even Hobbit-sized humans, size changes in island animals are well-known to science. Biologists have long believed that large animals evolving on islands tend to get smaller, while small animals tend to get bigger, a generalization they call "the island rule." A new study by researchers at Duke University and the National Evolutionary Synthesis Center in Durham, NC puts that old idea to the test in island and mainland rodents. "Some of the...