On the horizon
Getting to the nut of biodiversity
Biodiversity starts with the neighborhood oddball. That's the conclusion of a new study of tropical forests and why they contain such a broad variety of plants. An international team of scientists found that biodiversity builds as the least- common trees gain footholds and grow.
The results, they say, could help with recovery strategies for damaged areas where forest managers are trying to restore diversity.
The study focused on seven pristine forest plots in Southeast Asia and Latin America. Ranging from damp tropical forests to their dry counterparts, the forests shared a common trend: The older the established trees, the more diverse the forest became as newcomers arrived. The researchers, led by University of California at San Diego biologist Christopher Wills, suspect that the newcomers thrive because they have different resource needs than the longer-established trees, and the newbies aren't susceptible to the range of animals, fungi, and microbes that attack the well-established population.
Their results, which appear in the current issue of Science, raise questions about whether the same principle applies to temperate forests, coral reefs, and other ecosystems.
Talk with guys who like to fish, and they soon may begin to argue over who snagged the biggest. But the smallest?
Last week, researchers in Britain reported finding what they called the smallest fish and vertebrate known - a mature female Paedocypris progenetica measuring 7.9 millimeters. It was netted from a peat bog in Sumatra.
Not so fast, says the University of Washington's Ted Pietsch. Last fall, he published a study dealing with angler fish. One specimen, a mature male pulled from the deep ocean off the Philippines, measured a mere 6.2 millimeters.
One could be forgiven for missing it, however. It nearly gets lost after it finds a mate. Female angler fish measure about 46 millimeters. Tiny males attach themselves to the female with their teeth. (One female can play hostess to up to eight males.) They supply her reproductive needs. She provides food and transportation. Not a bad gig for either, given scientists' estimate that 80 percent of female angler fish swim the seas for 25 to 30 years - their whole lives - and never meet a mate.
Tired of that old suit? Turn it into a satellite. That's what International Space Station crew members will do Friday during a scheduled six-hour spacewalk. They've fitted a Russian Orlon space suit with ham-radio gear, a CD with images and artwork from students worldwide, a TV transmitter, and telemetry equipment. Voílà: SuitSat-1.
Russian engineers first conceived of the idea to celebrate the 175th anniversary of one of the country's leading technical universities. From there, the idea grew to become an educational tool for students worldwide.
The suit/satellite will beam back greetings from school children, as well as telemetry describing the satellite's condition and a simple TV picture. To encourage students to track SuitSat-1, greetings contain code words in different languages. Students who collect them all earn certificates. Ham-radio operators should be able to hear the satellite's FM signals on 145.99 Mhz as it passes overhead.
When it's first released, SuitSat-1 will track the space station's orbit fairly closely. But over time, its orbit will decay until it enters Earth's atmosphere and burns up. Planners expect the satellite to last for about six weeks.
