Ancient DNA Traces Woolly Mammoth's Disappearance:
Some ancient-DNA evidence has offered new clues to a very cold case: the disappearance of the last woolly mammoths, one of the most iconic of all Ice Age giants, according to a recent article. DNA lifted from the bones, teeth, and tusks of the extinct mammoths revealed a "genetic signature" of a range expansion after the last interglacial period. After the mammoths' migration, the population apparently leveled off, and one of two lineages died out.
Scientists Propose The Kind Of Chemistry That Led To Life:
Before life emerged on earth, either a primitive kind of metabolism or an RNA-like duplicating machinery must have set the stage - so experts believe. But what preceded these pre-life steps? A pair of UCSF scientists has developed a model explaining how simple chemical and physical processes may have laid the foundation for life. Like all useful models, theirs can be tested, and they describe how this can be done. Their model is based on simple, well-known chemical and physical laws.
The Fisherman Is A Predator Like Any Other:
For Peru fishing is a prime source of foreign exchange, second only to mining. The country's anchovy fishing fleet, which seeks the Peruvian anchovy Engraulis ringens, is the world's largest single-species fishery, with an average of 8% of global landings. For safety and monitoring purposes, vessels have the statutory obligation to be equipped with satellite geopositioning indicators, seeing that industrial-scale fishing is prohibited within a band of 5 nautical miles (about 9 kilometres) from the coast. This satellite device, the vessel monitoring system (VMS), gives the real-time position of the vessels to an accuracy of 100 m, communicated to bodies responsible for vessel movement recording and scientific monitoring of fishing.
The Insect Vector Always Bites Twice:
The reality of the threat from vector-borne diseases has been recognized and the problem is prompting research scientists to take a strong interest. Most of these infections, classified as emerging or re-emerging diseases, are linked to ecosystem changes, climatic variations or pressure from human activities. Malaria, sleeping sickness and so on lead to the death of millions of people in the world. African countries are particularly strongly hit. The expansion of Dengue fever and the recent epidemics of Chikungunya and West Nile disease illustrate the trend.
- Log in to post comments