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Full-Text Articles in Life Sciences

Meeting Of The Elephant Interest Group At Michigan State University, June 21, 1977, Jeheskel Shoshani Jul 1977

Meeting Of The Elephant Interest Group At Michigan State University, June 21, 1977, Jeheskel Shoshani

Elephant

Digest of the minutes of the first informal meeting of the Elephant Interest Group at the 57th Annual Meeting of the American Society of Mamalogists (ASM).


Stability Of Small Unisexual-Bisexual Populations Of Poeciliopsis (Pisces: Poeciliidae), William S. Moore Jul 1975

Stability Of Small Unisexual-Bisexual Populations Of Poeciliopsis (Pisces: Poeciliidae), William S. Moore

Biological Sciences Faculty Research Publications

All-female species of Poeciliopsis depend upon ♂ ♂ of closely related species for sperm. This relationship creates a competitive situation in which bisexual ♀ ♀ compete with unisexual ♀ ♀ for sperm from ♂ ♂ of the bisexual species. Earlier studies demonstrated a sufficient mechanism inherent in the behavior of ♂ ♂ for allowing coexistence in mixed unisexual-bisexual populations. Courtship preference of ♂ ♂ for conspecific ♀ ♀ is dynamically countered by social interaction among ♂ ♂ : subordinate males mate with unisexual ♀ ♀ in impetuous courtships. The Poeciliopsis monacha-Poeciliopsis 2 monacha-lucida complex occurs naturally in small isolated populations …


Coexistence In Unisexual-Bisexual Species Complexes Of Poeciliopsis (Pisces: Poeciliidae), William S. Moore, Frances E. Mckay Sep 1971

Coexistence In Unisexual-Bisexual Species Complexes Of Poeciliopsis (Pisces: Poeciliidae), William S. Moore, Frances E. Mckay

Biological Sciences Faculty Research Publications

All-female forms of Poeciliopsis rely on males of closely related bisexual species for sperm. The natural habitat of Poeciliopsis in Sonora, Mexico, consists of a variety of small ponds connected by intermittent watercourses. Optimal areas, containing mixed female aggregates, are defended by territorial males. Social structure in natural populations very closely resembles that of laboratory experiments, wherein subordinant males show reduced mate discrimination and inseminate unisexuals.

An equation relating male density to unisexual inseminations is used in a computer simulation model of a population. A stable equilibrium is inherent in unisexual-bisexual species complexes but the level of equilibrium is affected …