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Discovery of new fossils reveals key link in evolution of hind limbs

By Guest PostJanuary 19, 2014Natureafrican lungfish, brinson foundation, crocodile, data, discovery, drexel university, edward daeschler, evolution, first legged animals, fish, front wheel drive, harvard university, hind legs, hind limbs, key link, land dwelling tetrapods, large forefins, locomotion, neil shubin, new fossils, partial pelvic fin, pelves, shallow freshwater environments, tetrapods, tiktaalik roseae, transitional species, your inner fish

Researchers have discovered well-preserved pelves and a partial pelvic fin from Tiktaalik roseae, a 375 million-year-old transitional species between fish and the first legged animals, which reveal that the evolution of hind legs actually began as enhanced hind fins. This challenges existing theory that large, mobile hind appendages were developed only after vertebrates transitioned to land.

The scientists describe the fossils in the Proceedings of the National Academy of Sciences, online on Jan. 13. The piece marks the inaugural article for Prof. Neil Shubin, Robert R. Bensley Distinguished Service Professor of Organismal Biology and Anatomy, as a member of the National Academy of Sciences. (more…)

The Original Twitter? Tiny Electronic Tags Monitor Birds’ Social Networks

By Guest PostSeptember 24, 2012Nature, Sciencearchipelago, bird, brian otis, broadcast, costa rica, crow, drexel university, ecology, encounternet, forest, frequency, galapagos islands, german, internet, islands, john burt, lysanne snijders, Netherlands, new caledonia, radio tracking, radio transmitter, scotland, social behavior, social mobility, social network, South Pacific, st andrews, Technology, university, Washington, wireless sensor, woodland bird

If two birds meet deep in the forest, does anybody hear? Until now, nobody did, unless an intrepid biologist was hiding underneath a bush and watching their behavior, or the birds happened to meet near a research monitoring station. But an electronic tag designed at the University of Washington can for the first time see when birds meet in the wild.

A new study led by a biologist at Scotland’s University of St. Andrews used the UW tags to see whether crows might learn to use tools from one another. The findings, published last week in Current Biology, supported the theory by showing an unexpected amount of social mobility, with the crows often spending time near birds outside their immediate family. (more…)

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Discovery of new fossils reveals key link in evolution of hind limbs

The Original Twitter? Tiny Electronic Tags Monitor Birds’ Social Networks