A sedan-size turtle

Paleontologists have unearthed the remnants of a colossal turtle that patrolled northern South America some 10 million years ago. The Stupendemys geographicus grew up to 13 feet long and weighed 1.25 tons, and inhabited a giant wetland that once covered the region. These creatures were built for battle, reports Reuters.com. Fossils dug up in Colombia’s Tatacoa Desert and Venezuela’s Urumaco region—including a 9½-foot-long shell, the biggest ever found—show that males had front-facing horns on their shells that they may have used to tussle with other males over mates. Some Stupendemys fossils have bite marks and punctured bones, evidence of skirmishes with giant crocodilians. The enormous turtle’s diet “was diverse, including small animals—fish, caimans, snakes—as well as mollusks and vegetation,” said lead researcher Edwin Cadena, from the Universidad del Rosario in Colombia. The turtles died out about 5 million years ago, after the formation of the Andes dried out their watery habitat.

blows in from other states, new research shows. The study is the first to detail the sources and effects of two major harmful airborne pollutants, ozone and fine airborne particles, in the lower 48 states. By plugging pollution data from 2005 to 2018 into computer models, researchers were able to work out exactly where and how much pollution was traveling in the atmosphere. They found that in 30 states, the majority of premature deaths linked to poor air quality were caused by out-of-state pollution. New York was the largest “net importer” of early mortality, with nearly two-thirds of premature deaths attributable to out-of-state pollution. The states whose exported pollution led to the most deaths were in the Northern Plains and Upper Midwest. Interestingly, the scientists found that pollution regulations have reduced the number of cross-state deaths from electricity generation and road transportation, and that residential and commercial emissions are now the leading cause of premature deaths. “Future research and future policy are going to have to bear down on these emissions,” coauthor Steven Barrett, of the Massachusetts Institute of Technology, tells The New York Times.

“self-propelled microscopic grenades” are designed to stun and kill small fish and other prey; once the target is neutralized, the jellyfish sucks it in by pulsating. “It’s a real evolutionary novelty,” Ames tells New Scientist. She and her team put brine shrimp into a tank with the jellyfish. The jellies released their stinging proxies, named cassiosomes, which killed the brine shrimp in under a minute. Cassiosomes can survive outside their hosts for up to 10 days in the lab, likely because the algae within them generates energy through photosynthesis. The discovery explains why divers have reported feeling “stinging water” in the vicinity of upside-down jellyfish.