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At least 1,099 records · Page 61Linked to original sources
USGS1986

Frozen gene pools - A future for species otherwise destined for extinction

Conclusion: Semen banks and ova and embryo banks can be practical methods to maintain gene pools. Gene pool preservation is desperately needed today due to the rapid decline in number of species and their habitat, a matter that is of concern to.biologists, economists, and politicians worldwide. Techniques are available for the cryopreservation of semen from many animals (and embryos from a few mammals) and adaptations of these techniques to other animals should be possible. A frozen gene pool in conjunction with existing programs makes it possible to preserve gene pools at less cost or in.some cases where no other alternative to extinction existed.

American Association of Zoological Parks and Aquar↗
USGS1987

Populations of trap-nesting wasps near a major source of fluoride emissions in western Tennessee

Trap-nesting wasps were collected from eight sites at distances of from 1.2-33.0 km from an aluminum reduction plant in western Tennessee. The sites had similar topographies, soils, and vegetation, but differed in their exposure to fluoride, which was emitted in large quantities from the plant. It was postulated that if fluoride emissions had greatly changed the insect community then relative densities of their predators would have varied accordingly. However, the degree of fluoride pollution was unrelated to the relative densities of the wasps and to the number of cells provisioned with prey. Monobia quadridens, Trypargilum clavatum, and T. lactitarse were found to have two complete generations in western Tennessee. Trypargilum collinum rubrocinctum has at least two generations, and Euodynerus megaera probably has three generations. Six other wasp species and a megachilid bee were also collected.

Proceedings of the Entomological Society of Washin↗