Word: dna
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Dates: during 1990-1999
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...well: they're a lot more promiscuous than people are. Even though bacteria can reproduce asexually by splitting in two, they often link up with other microbes of the same species or even a different species. In those cases, the bacteria often swap bits of genetic material (their DNA) before reproducing...
They have many other ways of picking up genes as well. The DNA can come from viruses, which have acquired it while infecting other microbes. Some types of pneumococcus, which causes a form of pneumonia, even indulge in a microbial version of necrophilia by soaking up DNA that spills out of dead or dying bacteria. This versatility means bacteria can acquire useful traits without having to wait for mutations in the immediate family...
Unlike bacteria and protozoans, which are full-fledged living cells, capable of taking in nourishment and reproducing on their own, viruses are only half alive at best. They consist of little more than a shell of protein and a bit of genetic material (DNA or its chemical cousin RNA), which contains instructions for making more viruses -- but no machinery to do the job. In order to reproduce, a virus has to invade a cell, co-opting the cell's own DNA to create a virus factory. The cell -- in an animal, a plant or even a bacterium -- can be physically...
There's a new use for DNA testing: tracking illegal whaling practices, according to a report in Science magazine. Researchers used portable equipment to test whale meat being sold in Japan, where the product is an expensive delicacy. The presence of protected minke, fin and humpback whales as well as dolphin were found in several of the samples, indicating that banned meat was being sold. The genetic test could provide a policing mechanism in the future...
...resolved today, at least to the satisfaction of a Russian panel. Participants declared she was killed during the Bolshevik execution of her family in 1918. Since then, several women have claimed to be Anastasia, insisting that the young girl survived the killing. Last year British experts conducting DNA tests on the remains of the royal family could only confirm the identities of the Czar, his wife and three of the four daughters. The more recent Russian study concludes that the bones of the Romanov son Alexei and his sister Maria, not Anastasia, were missing...