Magazine
May-June 2001
May-June 2001
Volume: 89 Number: 3
En route to their spawning grounds, chum salmon battle the falls of the McNeil River, about 400 kilometers southwest of Anchorage, Alaska. Chum and the six other salmonid species inhabiting the Pacific Northwest face growing threats to their survival as development of the region expands. Efforts to conserve these fish are in place, but as Phillip S. Levin and Michael H. Schiewe explain in "Preserving Salmon Biodiversity," conservationists and wildlife managers sometimes overlook the importance of maintaining the genetic wealth of the many salmonid stocks in a quest to boost the dwindling numbers of fish. (Photograph by Daniel J. Cox/naturalexposures.com.)
In This Issue
- Astronomy
- Biology
- Chemistry
- Communications
- Computer
- Engineering
- Environment
- Evolution
- Mathematics
- Medicine
- Physics
- Policy
- Psychology
- Technology
Preserving Salmon Biodiversity
Phillip Levin, Michael Schiewe
Environment
The number of Pacific salmon has declined dramatically. But the loss of genetic diversity may be a bigger problem.
Combing Chromosomes
John Herrick, Aaron Bensimon
Biology
Extending DNA and labeling specific sequences pinpoints chromosomal features and unravels natural and disease processes
How Were the Comets Made?
Joseph Nuth
Astronomy
Explaining the composition of these 4.5 billion-year-old relics may require scientists to revise their models of the primitive solar nebula
