BIOLOGISTS UNCOVER DARWIN'S "MISSING EVIDENCE" FOR DIVERGENCE OF SPECIES--IN A WARBLER'S SONG Biologists funded by NSF and affiliated with the University of California at San Diego (UCSD) have demonstrated, in a study of the songs and genetics of a series of interbreeding populations of warblers in central Asia, how one species can evolve into two. The investigators have discovered intermediate forms of two reproductively isolated populations of songbirds that no longer interbreed. This work provides evidence predicted by Darwin in support of his theory of evolution. "One of the largest mysteries remaining in evolutionary biology is exactly how one species can gradually diverge into two," says Darren Irwin, a biologist at UCSD who headed the study. "This process, known as speciation, is very difficult to study because it can take a great deal of time to occur." The warbler is the first case in which "we can see all the steps that occurred in the behavioral divergence of two species from their common ancestor," says Irwin. "These results demonstrate how small evolutionary changes can lead to the differences that cause reproductive isolation between species, just as Darwin envisioned." [Cheryl Dybas]
Survive? Resources Use the BACK button in your browser to return to this page. EBS
Breaking News Science activities in Survive? allow students to explore the environmental pressures that shape a population and lead to changes over time. As with all Event-Based Science modules, much of the information that students need is provided in the pages of Survive?. However, more information is needed. Information from the Web about animals, heredity, diversity, and evolution will add to the authenticity of your study. Below are some World-Wide Web sites where additional information is available. Click on the highlighted words and be linked with helpful sites. Links to Survive?
related WEB Sites
| |||||||||||||||||||
Survive? allows students to explore
concepts related to animals, heredity, diversity, survival of
the fittest, and evolution in the context of the discovery of
deformed frogs in
Minnesota.
Click here to
use Google News to search and browse 4,500 continuously
updated news sources for breaking news about evolution and
heredity
|
|
-
The North American Reporting Center In cooperation with the scientific community, this Web site has been designed as place where people can report sightings of amphibian malformations in North America. If you have observed malformed amphibians, or if you have handled a number of wild amphibians but not noted any abnormalities, they urge you to report your sightings by going to How Can I Submit a Report? on their site.
-
Animal Diversity -- a collection of pictures and information about animals supported by the University of Michigan's Museum of Zoology.
-
Where Frogs Live Feature article discussing the effects of environmental conditions on amphibians.
|
 |
- Deformed Frogs in Minnesota Deformed frogs were discovered in Minnesota in 1995. This site will help you learn more about where the deformed frogs were first found, why we are concerned about deformed frogs, what is being done about the problem and what you can do to help.
- Owl Pellets are available from Nature's Classroom.
Video - A Green Frog
