Old Weblog - December 2005

Oldest bird had dinosaur feet (New Scientist: 01-Dec-05)
The oldest known bird was closer to a dinosaur than previously thought—a discovery that confuses the evolutionary tree as we currently understand it. An exceptionally well preserved new fossil reveals a foot and skull that more closely resemble those of a group of two-legged predatory dinosaurs called dromeosaurs, than modern birds.
The Earth's greatest mass extinction was probably caused by poisonous volcanic gas, according to a study published in the journal Geology. This "great dying" 250 million years ago killed off more than two-thirds of reptile and amphibian families. But it also facilitated the rise of the dinosaurs, which would rule Earth for the next 185 million years.
A mysterious red furry creature, captured on film in the dense forests of Borneo, could be a new species of carnivore. The mammal, which is slightly larger than a domestic cat, has dark red fur and a long, bushy tail. It was snapped twice at night by a camera trap set up by researchers from the conservation group WWF. Its general shape—with a possibly pointed snout, small ears, and large powerful hind legs—suggests it is a meat-eater. It has some similarities with martens or civets and could belong to these groups, or it may belong to an entirely new group, says WWF.
Scientists have identified a major climate crisis that struck Africa about 70,000 years ago and which may have changed the course of human history. The evidence comes from sediments drilled up from the beds of Lake Malawi and Tanganyika in East Africa, and from Lake Bosumtwi in Ghana. It shows equatorial Africa experienced a prolonged period of drought. It is possible, scientists say, this was the reason some of the first humans left Africa to populate the globe.
The brainier male bats are, the smaller their testicles, according to a new study. Researchers suggest the correlation exists because both organs require a lot of energy to grow and maintain, leading individual species to find the optimum balance. The analysis of 334 species of bat found that in species where the females were promiscuous, the males had evolved larger testes but had relatively small brains. In species, where the females were monogamous, the situation was reversed. Male fidelity appeared to have no influence over testes or brain size.