Cells from the smallest to the largest of mammals often seem to be "one size fits all." Now a closer look reveals that whether a cell lives in an elephant, mouse or something in between can make a big difference in its life. Researchers from the University of Florida Genetics Institute, Harvard Medical School and other institutions developed mathematical models that they used to examine 18 cell types from mammals ranging from mice to elephants. They found two basic categories -- cells that stay the same size but have drastically different energy needs that depend on the size of the mammal, or cells that grow larger in larger mammals and use energy at the same rate, no matter the mammal's size.
Bacteria are known to share genes, spreading drug resistance, for example. But how common is it in other organisms, including mammals like us? Two new studies show that most bacteria have genes or large groups of genes shared by other bacteria. Even among higher organisms, shared genes are the rule rather than the exception, UC Berkeley and LBNL researchers say.
Like a piece of chalk dissolving in vinegar, marine life with hard shells is in danger of being dissolved by increasing acidity in the oceans. Ocean acidity is rising as sea water absorbs more carbon dioxide released into the atmosphere from power plants and automobiles. The higher acidity threatens marine life, including corals and shellfish, which may become extinct later this century from the chemical effects of carbon dioxide, even if the planet warms less than expected.
The brain appears to process information more chaotically than has long been assumed. This is demonstrated by a new study conducted by scientists at the University of Bonn. The passing on of information from neuron to neuron does not, they show, occur exclusively at the synapses, i.e. the junctions between the nerve cell extensions. Rather, it seems that the neurons release their chemical messengers along the entire length of these extensions and, in this way, excite the neighbouring cells.
The sperm whale and its large prey, the jumbo squid, are among the deepest divers in the ocean, routinely reaching depths of 3,000 feet or more. Now, in a new study, a team of marine scientists reports the successful tagging of sperm whales and jumbo squid swimming together off Mexico's Pacific coast--the first time that electronic tracking devices have been applied simultaneously to deep-diving predators and prey in the same waters.
A plague of ticks, stifling hot summers and relentless pressure from wolves have driven the moose population on Isle Royale National Park to its lowest ebb in at least 50 years.
A petition to provide Endangered Species Act protection for the longnose sucker, a fish, in the Monongahela River drainage of West Virginia, Maryland and Pennsylvania failed to provide substantial scientific information indicating that protection could be warranted, according to Martin Miller, chief of endangered species for the U.S. Fish and Wildlife Service's Northeast Region.