A stimulatory phalloid organ in a weaver bird
Article Abstract:
Red-billed buffalo weavers, B. niger possess a phalloid organ which is a stiff rod of connective tissue lying anterior to the cloaca, and having no ducts. In a study mounting was found to be similar to that in other birds, although the male adopted a reclining position, and the phalloid organ appeared to be rubbed against the cloacal region of the female. It is suggested that the phalloid organ is a stimulatory organ that could have evolved in response to intense sperm competition mediated, by a polygyandrous mating system.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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Bi-directional plasma jets produced by magnetic reconnection on the Sun
Article Abstract:
Magnetic reconnection is seen as the explanation for plasma kinetic energy surges causing events such as solar flares. The observational evidence for reconnection is based on observations of solar X-ray morphology variations, and sudden magnetic topology changes. Ultraviolet observations, revealing the presence of bi-directional plasma jets emitted from small sites above the solar surface, are described. These observations lend support to the theory that reconnection accelerates plasma on the Sun.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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Female mate-choice drives the evolution of male-biased dispersal in a social mammal
Article Abstract:
The male-biased dispersal in the spotted hyaena (Crocuta crocuta) has resulted from an adaptive response by males in simple female mate-choice rules that have evolved to avoid inbreeding. The extent of male dispersal as a response to female mate-choices has depended on the demographic structure of breeding groups, rather than the genetic relatedness between females and males.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2007
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