As we get towards the end of our fabulous tour of biology it's time to catch up with some advances and events that have taken place during the last few months. A brief snippet from each and a link. Enjoy.
Rise Of Oxygen Caused Earth's Earliest Ice Age
Geologists may have uncovered the answer to an age-old question - an ice-age-old question, that is. It appears that Earth's earliest ice ages may have been due to the rise of oxygen in Earth's atmosphere, which consumed atmospheric greenhouse gases and chilled the earth.
Scaling of Soaring Seabirds and Implications for Flight Abilities of Giant Pterosaurs
Giant pterosaurs, colossal winged reptiles that lived alongside the dinosaurs, have long been considered the heaviest animals ever to take to the skies. But new research suggests that the notion of giant pterosaurs soaring over Earth simply doesn't fly.
Congruence of morphologically-defined genera with molecular phylogenies
Scientists using molecular techniques assert that genetics more accurately determines evolutionary relationships than does a comparison of physical characteristics preserved in fossils. But how inaccurate, really, were the fossils? Jablonski and Finarelli compared the molecular data to data based on the kinds of features used to distinguish fossil lineages for 228 mammal and 197 mollusk lineages at the genus level.
No matter how they looked at it, the lineages defined by their fossil forms "showed an imperfect but very good fit to the molecular data," Jablonski said. The fits were generally far better than random. The few exceptions included freshwater clams, "a complete disaster," he said.
Jablonski interprets the results as good news for evolutionary studies. The work backs up a huge range of analyses among living and fossil animals, from trends in increasing body size in mammal lineages, to the dramatic ups and downs of diversity reported in the fossil record of evolutionary bursts and mass extinctions.
Two studies add a new twist to the plot. One claims that the skeleton's ape-like feet push back its ancestry near the dawn of Homo. Another argues that the hobbit is a later offshoot of Homo erectus, dwarfed by aeons of island isolation.
Swine Flu: the Predictable Pandemic
New Scientist has a collection of articles on Swine Flu that are really good at answering the various questions you might have
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