(Santa Barbara, Calif.) — — Scientists at UC Santa Barbara have discovered a caste of genetically identical “warrior worms” — — members of a parasitic fluke species that invades the California horn snail. The findings are reported in the …
Biodiversity worldwide may be decreasing, but at smaller scales it is increasing or at least changing in composition, suggesting the need for a dramatic shift in the current focus of ecological research. These changes may undermine the functioning of local ecosystems, according to an article in December’s American Naturalist. The authors studied data collected on oceanic island land birds and plants. Records from islands are useful because they present discrete areas where additions and subtractions of species can be accurately determined. The article, “Species Invasions Exceed extinctions on Islands Worldwide: A Comparative Study of Plants and Birds,” documents the fact that “land birds have experienced massive extinctions on oceanic islands, with many islands losing more than half of their native species,” said Gaines. “On these same islands, however, many exotic bird species have become established, such that the total number of land bird species has remained relatively unchanged.”
Although it is expected that populations of many organisms will move away from the equator and toward the poles to stay cool during global warming, researchers have found that the intertidal zone does not exactly fit this pattern. A study published in this week’s Science Magazine indicates that there may be “hot spots” at northern shoreline sites within the next three to five years. This is partly due to the timing of the tides.