Tag Archives: genus

International Research Team Close Human Evolution Gap with Discovery of 1.4 Million-Year-Old Fossil Human Hand Bone

University of Missouri researcher part of team that found the bone in Kenya

COLUMBIA, Mo. – Humans have a distinctive hand anatomy that allows them to make and use tools. Apes and other nonhuman primates do not have these distinctive anatomical features in their hands, and the point in time at which these features first appeared in human evolution is unknown. Now, a University of Missouri researcher and her international team of colleagues have found a new hand bone from a human ancestor who roamed the earth in East Africa approximately 1.42 million years ago. They suspect the bone belonged to the early human species, Homo erectus. The discovery of this bone is the earliest evidence of a modern human-like hand, indicating that this anatomical feature existed more than half a million years earlier than previously known. (more…)

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A Whole New Meaning for Thinking on Your Feet

Smithsonian researchers report that the brains of tiny spiders are so large that they fill their body cavities and overflow into their legs. As part of ongoing research to understand how miniaturization affects brain size and behavior, researchers measured the central nervous systems of nine species of spiders, from rainforest giants to spiders smaller than the head of a pin. As the spiders get smaller, their brains get proportionally bigger, filling up more and more of their body cavities.

“The smaller the animal, the more it has to invest in its brain, which means even very tiny spiders are able to weave a web and perform other fairly complex behaviors,” said William Wcislo, staff scientist at the Smithsonian Tropical Research Institute in Panama. “We discovered that the central nervous systems of the smallest spiders fill up almost 80 percent of their total body cavity, including about 25 percent of their legs.” (more…)

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Infectious Fungus, Thought to Be Asexual, Isn’t

*Candida tropicalis turns out to have sex, making it the second medically important member of the genus to be capable of mating. Sex may improve the survival of the species, particularly when it’s under pressure. It may also mean the species can achieve greater virulence or drug resistance more quickly than previously thought.*

PROVIDENCE, R.I. [Brown University] — The fungi of the Candida genus, known to millions of patients worldwide for their ability to cause serious infections, were once all thought to be asexual. Even after scientists discovered that the mating habits of Candida albicans were many and varied, they remained convinced that many of the more infectious ones did not mate. Now with the first report that Candida tropicalis can mate sexually as well, the chastity of the whole genus comes into further doubt. (more…)

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