Colombia es el país con mayor diversidad de aves en el planeta

ORIGINAL: Noticias Ambientales

01/ 02/ 2013

Colombia mantiene su condición, con 1.897 especies catalogadas, según la revista científica local Conservación.

Según la publicación, le siguen Perú, con 1.834; y Brasil, con 1.785. Según refiere, durante el 2012 fueron descubiertas ocho nuevas especies por los investigadores Thomas Donegan, Alonso Quevedo, Paul Salaman y Miles McCullan, quienes tuvieron a su cargo la revisión anual del Libro Aves de Colombia, que se dedica al tema.

Entre estas figuran, ilustradas con fotos, el Troglodytes montícola o Cucarachero de Santa Marta, en peligro de extinción, que habita en una pequeña zona de páramo, 2.250 metros sobre el occidente de la Sierra Nevada, en el norte del país. Otras especies registradas fueron la pavita roja (Haematoderus militaris) y el Turdus sanchezorum.

A estas se agrega la cacatúa galerita ( Melopsittacus undulatus), un ave exótica, de especie recién confirmada. Tanto Donegan como Alonso destacaron los programas de conservación desarrollado en los últimos años por la Fundación Proave. La buena nueva contrasta con la alarma que cunde ante las tasas de deforestación prevalecientes.

Deep Sea Vents: Science at the Extreme

ORIGINAL: Environment.nationalgeographic.com

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Deep sea vents in the Atlantic Ocean’s Mid-Atlantic Ridge support tubeworms, eelpout fish, and crabs. The Mid-Atlantic Ridge is an underwater mountain chain that extends about 10,000 miles (16,000 kilometers) from the Arctic Ocean to the southern tip of Africa. Photograph by Emory Kristof

Republished from the pages of National Geographic magazine

With a mile and a half (two and a half kilometers) of Pacific Ocean sitting on their shoulders, ghost-pale crabs and fish forage among blood-red tube worms. Such communities flourish where super-heated water gushes from seafloor springs. Advances in the tools that scientists use to investigate deep-sea ecosystems are expanding knowledge of these creatures and their hostile environment.

Strange Life Clearly Seen

Water heated as high as 760°F (404°C) by magma from Earth's interior billows from a seafloor chimney. The surrounding ocean is just a few degrees above freezing. When the two fluids meet, iron sulfide precipitates, giving the "black smoker" its color. In these dark depths, chemosynthesis—based on thermal and chemical energy from the vents—is the primary mechanism sustaining life.

A living cloud flecks the water around a clump of limpet-encrusted tube worms and mustard-yellow mussels in the high-definition image at far right. With a magnifying lens on another camera the cloud resolves into a crowd of flea like crustaceans called amphipods. Amphipod swarms like this one—observed at 9° N on the East Pacific Rise—may be the densest concentrations of invertebrate life on Earth.

High-intensity lighting and high-resolution imaging technologies provide researchers with the equivalent of a microscope to examine life in the deep sea. These tools can reveal organisms that have always been part of vent communities but have been hidden until now.

Timothy Shank, a marine ecologist at Woods Hole Oceanographic Institution, calls the array of previously unknown species found at vents "mind-boggling." He has calculated that, on average, a new species has been described every week and a half since biologists first visited the Galápagos Rift vents in 1979. "More than 20 years later," he says, "we're still on the tip of the iceberg. We're trying to understand relationships among vent animals—and we're still discovering new species!"

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