Bytes

hiv origin: The origin of HIV that causes AIDS has been found in wild chimpanzees living in southern Cameroon, according to an international team of scientists. A virus called SIVcpz (Simian Immunodeficiency Virus from chimps) was thought to be the source, but had only been found in a few captive animals. Now, a natural reservoir of SIVcpz in animals living in the wild has been identified.

It is thought that people hunting chimpanzees first contracted the virus in the Democratic Republic of Congo in 1930. The fact that symptoms of AIDS differ vastly between individuals explains why it was another 50 years before the virus was named.

poison ivy: Global warming may encourage a more prolific growth of poison ivy and also make it itchier, say scientists from the Duke University in the US. The noxious vine grows faster and bigger as carbon dioxide levels in the atmosphere rise. The scientists conducted experiments in which they increased the carbon dioxide levels to those expected in 2050 and observed the effects on the plant. More carbon dioxide also encourages the vine to produce more of its rash-causing chemical, urushiol, they say.