Earthweek: a diary of the planet

Altered evolution

Humankind is wielding so much influence on the natural world that we are reshaping the evolution of many species.

Researcher Sarah Otto, of the University of British Columbia, wrote in the Proceedings of the Royal Society B that the altered evolution includes some fish growing mouths that are smaller and harder to hook by fishermen, and swallows developing smaller, more maneuverable wings to help them navigate through buildings and traffic.

She also says that some mammals are becoming nocturnal to avoid conflict with humans.

“Human impacts on the world are not just local,” she said. “They are changing the course of evolutionary history for all species on the planet, and that’s a remarkable concept to ponder.”

Earthquakes

A light tremor rattled Italy’s northeastern coast, near Venice. Earth movements also were felt along the CaliforniaMexico border and in northwestern Washington. Rainiest days

Half of the precipitation that falls each year around the world occurs during just 12 very wet days, according to a new study of satellite and weather station data.

Researcher Angeline Pendergrass, of the U.S. National Center for Atmospheric Research in Boulder, Colorado, found that climate change is causing the rainiest days to get wetter, and she predicts that half of the annual precipitation worldwide probably will fall in just 11 days by the end of this century.

“While climate models generally project just a small increase in rain in general, we find this increase comes as a handful of events with

much more rain and, therefore, could result in more negative impacts, including flooding,” Pendergrass said.

Horned rule

Swiss citizens are slated to vote this week whether to subsidize farmers who let their cows and goats grow horns to their natural length. The referendum on the “dignity of livestock” aims to fund extra grazing space that the horned animals need to reduce dehorning.

“We must respect cows as they are. Leave them their horns,” referendum advocate and farmer Armin Capaul told Reuters. “When you look at them, they always hold their head high and are proud. When you remove the horns, they are sad.” The government opposes the move, saying it will take funding from the agricultural budget.

Earth eats water

Scientists have discovered that the movement of Earth’s tectonic plates is dragging three times more water into the planet’s interior than thought. Writing in the journal Nature, Chen Cai of Washington University in St. Louis and his colleagues describe the process of subduction, in which hot ocean- floor plates grind together and pull water deep into the crust and mantle.

By using seismic sensors placed in the Marianas Trench, the team was able to more accurately estimate how much water was being locked up in hydrates and rocks during the process. That stored water is believed to make quakes more likely by lubricating faults.

Tropical cyclone

Late reports from southern India say nearly 50 people perished when Cyclone Gaja passed over Tamil Nadu state Nov. 16. Officials said the storm toppled 30,000 utility poles and uprooted more than 100,000 trees. Nearly 82,000 people took refuge in government-run shelters.

Eruption

The fifth eruption of Guatemala’s Fuego volcano this year prompted around 4,000 people to flee lava flows as well as swiftly moving clouds of super- heated ash and vapor. An eruption in June obliterated entire villages and left nearly 200 people dead. Activity also increased recently inside two of Guatemala’s other restive volcanoes, Pacaya and Santiaguito.