The evolution of beer yeasts, seedy pants and vampire bat venom-turned medicine

Beer yeasts: Researchers at Lund University in Sweden tracked the history of two yeasts—Saccharomyces cerevisiae and Dekkera bruxellensis—used in alcohol fermentation to pinpoint their role in ethanol production. They found that, around 150 million years ago, competition with other microbes, and the overall increase in sugar-rich fruits, encouraged the yeasts to withstand high ethanol concentrations—an adaptation that would allow them to survive in places other microbes could not. “Now, scientists are closing in on just how and why yeast evolved to [ferment sugars into alcohol],” wrote John Roach in an MSNBC article. “No, it wasn’t to get humans drunk.” Read more at “The why of yeast’s buzz-giving ways” or the press release “Wine yeasts reveal prehistoric microbial world.” Camouflaged cuttlefish: “Cuttlefish are masters of camouflage. Like their relatives, the squid and the octopus, cuttlefish can change the colour of their skin to perfectly match a bed of pebbles, a clump of algae, or a black-and-white chessboard,” wrote Ed Yong of Not Exactly Rocket Science (see below video of previous research). Alexandra Barbosa from the University of Porto found that cuttlefish use visual cues to alter their appendages as well. In other words, when the cephalopods were placed against backgrounds of various striped patterns, they adjusted their tentacles to match the pattern that they saw. Read more and see photos at “Pocket Science – will all camouflaged cuttlefish please raise their tentacles?” Seedy pants: One of the most topical quotes this week—“I wish nature would stop getting it on in my eyeballs”—was uttered by a fellow allergy sufferer. Allergy season is in full force in temperate locales, such as some parts of the U.S. East Coast, as trees flood the air with pollen in the hopes of reaching a female counterpart. There are several ways that pollen travels, such as the wind, but most of us have probably never considered the role of pants in tree pollination. Yes, pants not plants. As quoted in a recent NPR article, “‘Because of his great mobility,’ [British botanist Edward] Salisbury wrote (projecting from his personal data set), ‘man is probably the most active agent—though usually an unconscious one—for [the] external transport of seeds.’” Read more at “Strange Things Happen To Guys Who Wear Pants.” Vampire bat venom: Scientists have tapped vampire bat saliva as a potential medication for treating stroke in humans, and the drug is actually called “Draculin.” It was announced this week that the drug would enter Phase 2 tests. “When vampire bats bite their victims, their saliva releases an enzyme called desmoteplase, or DSPA, into the bloodstream, which causes blood to flow more readily,” wrote Patrick Morgan on Discover’s blog...

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From the Community: ecological research in July

Resistance to Bt crops, chaotic red queen, balancing research near Mount Saint Helens, biodiversity and species coexistence and camouflage in polymorphic Pygmy grasshoppers. Here is open-access research from the first week in July. Cropping up: From the article “Managing resistance to Bt crops in a genetically variable insect herbivore, Ostrinia nubilalis” by Megan E. O’Rourke, Cornell University, in Ecological Applications: Insect races within a single species may have very different ecologies despite being morphologically indistinguishable. This can have important implications for managing agricultural pest species that are composed of multiple races. The European corn borer is a classic example of an economically important agricultural pest for which management strategies and regulatory policies have largely ignored the potential differences between known host races. Chaotic red queen: In “Chaotic Red Queen coevolution in three-species food chains,” Fabio Dercole from Politecnico di Milano and colleagues write in Proceedings of the Royal Society Biological Sciences: Antagonistic coevolution describes the reciprocal evolutionary interactions between populations belonging to an ‘exploiter’ (such as a predator or a parasite) and a ‘victim’ (such as a prey or a host). It is a change in the genetic make-up of a population in response to a genetic change in the antagonistic population. Antagonistic interactions have the potential to drive coevolutionary dynamics of adaptive traits: an evolutionary advantage gained by one antagonist is often associated with a disadvantage for the other antagonist, and may therefore prompt a counteradaptation. Extreme field work: Author Douglas Larson recounts in “Science After the Volcano Blew” from American Scientist: On May 20, 1980, two days after the catastrophic eruption of Mount St. Helens, U.S. Geological Survey scientists landed in a helicopter near the volcano’s base, a short distance from what should have been the south shore of Spirit Lake. The lake, just 8 kilometers north-northeast of the volcano, was the largest of dozens of subalpine lakes battered by the eruption. Unable to see much that resembled a lake, the scientists suspected that Spirit Lake had either boiled away or was buried by avalanche debris. Further investigation revealed that the lake had survived, but it looked more like land than water because thousands of logs, tons of volcanic ash and other rubble blanketed its surface. The riches: In “More than ‘More Individuals’: The Nonequivalence of Area and Energy in the Scaling of Species Richness” from The American Naturalist, Allen H. Hurlbert from University of North Carolina, Chapel Hill and Walter Jetz from University of California, La Jolla start the article: Understanding spatial variation in species richness has long been a central focus of ecology, but while we have gained a solid appreciation for empirical patterns, less...

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