Population size differences may have driven loss of Neanderthal genes
Humans and Neanderthals interbred tens of thousands of years ago, but over time, natural selection has purged many Neanderthal genes from the human genome. To understand how modern humans lost these genes and how humans and Neanderthals remained distinct, researchers from the University of California, Davis, have developed a new method for estimating the average strength of natural selection against Neanderthal genetic material. Their findings were recently published, and according to lead author Ivan Juric, “The key finding in our study is that the current levels of Neanderthal ancestry in modern humans are in part due to long-term differences in human and Neanderthal population sizes.”
Rising CO2 levels could severely impact coral reefs and people who rely on them
Rising levels of atmospheric carbon dioxide lead to ocean acidification and rising sea surface temperatures – effects that pose a threat to shallow, warm-water coral reefs and the communities who depend upon them for fishing, tourism or as natural barriers to protect shorelines. In a recent study, researchers from the Université de Bretagne Occidentale in France identified countries where people would most likely be affected by coral reef habitat loss by 2050. “By 2050, coastal communities in Western Mexico, Micronesia, Indonesia, parts of Australia and Southeast Asia will bear the brunt of damage to coral reefs caused by rising temperatures and ocean acidification,” says Linwood Pendleton, the study’s lead author.
Mutations that enable drug resistance may also enhance growth of malaria parasite
Some genetic mutations that allow the malaria-causing parasite Plasmodium falciparum to resist drug treatment could also help the parasite grow, according to a new study from the Columbia University Medical Center in New York. The researchers used a gene editing technique to investigate how mutations to the P. falciparum gene known as pfcrt could enable drug resistance and growth in the parasite. Their findings contribute to scientists’ understanding of these genetic mutations, which could help inform future malaria treatment efforts.
Image Credit: Jaysmark, Flickr, CC BY