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El estatus social alto tiene sus privilegios cuando se trata de envejecimiento, incluso en los animales salvajes.

En el primer estudio en su tipo, que implica una especie silvestre, investigadores de la Universidad Estatal de Michigan han demostrado que los factores sociales y ecológicos afectan a la salud animal. Los resultados, publicados en la edición actual de Biology Letters, se centraron en las hienas manchadas de Kenia.

A century-long study in the Oregon Cascades may cause scientists to revise the textbook on how forests grow and die, accumulate biomass and store carbon.

In a new analysis of forest succession in three Douglas-fir stands in the Willamette National Forest, two Oregon State University scientists report that biomass – a measure of tree volume – has been steadily accumulating for 150 years. In the long term, such a trend is not sustainable, they said, and if these stands behave in a manner similar to others in the Cascades, trees will begin to die from causes such as insect outbreaks, windstorms or fire.

“Mortality will occur in the future,” said Mark Harmon, professor and Richardson Chair in Forest Science at OSU. “It just hasn’t arrived.”

A new study “provides evidence that methane seeps are island-like habitats that harbor distinct microbial communities unique from other seafloor ecosystems." These seeps play an important role in microbial biodiversity of the sea floor.

Methane seeps are natural gas leaks in the sea floor that emit methane into the water. Microorganisms that live on or near these seeps can use the methane as a food source, preventing the gas from collecting in the surrounding hydrosphere or migrating into the atmosphere.

“Marine environments are a potentially huge source for methane outputs to the atmosphere, but the surrounding microbes keep things in check by eating 75 percent of the methane before it gets to the atmosphere. These organisms are an important part of the underwater ecosystem, particularly as it relates to global gas cycles that are climate important in terms of greenhouse gas emissions,” said University of Delaware assistant professor of marine biosciences, Jennifer Biddle.

Uplift associated with the Great Rift Valley of East Africa and the environmental changes it produced have puzzled scientists for decades because the timing and starting elevation have been poorly constrained.​

Now paleontologists have tapped a fossil from the most precisely dated beaked whale in the world - and the only stranded whale ever found so far inland on the African continent - to pinpoint for the first time a date when East Africa's mysterious elevation began.

The 17 million-year-old fossil is from the beaked Ziphiidae whale family. It was discovered 740 kilometers inland at an elevation of 620 meters in modern Kenya's harsh desert region, said vertebrate paleontologist Louis L. Jacobs, Southern Methodist University, Dallas.

Researchers at Sandia National Laboratories’ Z machine have helped untangle a long-standing mystery of astrophysics: why iron is found spattered throughout Earth’s mantle, the roughly 2,000-mile thick region between Earth’s core and its crust.