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| For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Bill Noxon Contents of this Tipsheet:
RECREATING A SPECIES: EVOLUTION TURNS PREDICTABLEIf a daisy were given another chance at evolution, would it still look like a daisy? Would a rose still smell like a rose? Scientists have long wondered how much of a role chance plays in evolution, and the answer, at least for one species of sunflower, is not much. If the 100,000-year-old species developed all over again, it would still be the same, according to NSF-funded evolutionary biologist Loren Rieseberg of Indiana University in Bloomington. This is a surprising finding, since much of evolutionary theory suggests that chance is a significant player in speciation. Rieseberg conducted research on this question by studying the anomalous sunflower, Helianthus anomalus, a naturally occurring hybrid that developed from the interbreeding of two sunflowers: the common sunflower (Helianthus annuus) and the petioled sunflower (Helianthus petiolaris). Rieseberg assumed he could interbreed the two parent species and get another flower, but he didn't know if he would still get the anomalous sunflower, or a totally new species. In all his trials, the anomalous sunflower appeared within four generations. And not only did the flowers look like their counterparts of the Great Basin desert, DNA testing showed that they were almost identical. "I was pretty astonished," says Rieseberg. "I expected to see some similarities, but I didn't expect to see anything like this. I think we'll find that much more about evolution is repeatable and predictable than we had thought." [Cheryl Dybas] SCIENTISTS DISCOVER SMALLEST FROG
Scientists funded by the National Science Foundation have discovered, in Cuba, the smallest frog in the Northern Hemisphere. It is one centimeter long and the smallest of the tetrapods, a grouping that includes all animals with backbones except fishes. This newly discovered tiny tetrapod is tied for the world record with the smallest frog found in the Southern Hemisphere, according to Pennsylvania State University biologist Blair Hedges in a paper published in the December issue of the journal Copeia. Hedges and his Cuban colleagues discovered the tiny orange-striped black frog living under leaf litter among the roots of ferns in a humid rain forest on the western slope of Cuba's Monte Iberia. Hedges and Cuban scientist Alberto Estrada gave the frog the scientific name Eleutherodactylus iberia. Those two words are more than three times longer than the frog itself. Hedges and Cuban scientists have a history of discovering new species of snakes, lizards, and frogs in Cuba's rain forests. One is a lizard tied for the world's tiniest. "You don't often find species that are the smallest, especially in a big group like tetrapods," Hedges said. [Cheryl Dybas] GRANTS FROM NSF AUGMENT AND FOSTER RESEARCH AT ST. LOUIS HERBARIUMMore than 4.5 million specimens make the St. Louis, Missouri Botanical Garden's herbarium one of the nation's largest. Adding up to 200,000 new acquisitions every year, the herbarium will have a collection of 5.3 million specimens by the turn of this century. The National Science Foundation (NSF) has recently awarded the herbarium a grant for its research center that will allow for a near doubling of the harburium's storage capacity. This precludes portions of the collection from having to be placed in permanent storage, inaccessible to researchers. From another recent NSF grant, the Missouri Botanical Garden conducted a large symposium in St. Louis on new tools for investigating biodiversity. More than 450 scientists from around the world discussed questions in systematic biology, a field that documents the diversity of organisms and groups them in ways that reflect their evolutionary relationships. The availability of cheaper, faster computers has opened up new possibilities for studying biodiversity, and according to attending scientists, is leading to new opportunities for breakthroughs in this field. [Cheryl Dybas]
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