Publications by authors named "H H Heatwole"

Dehydration and drinking behaviors were investigated in the little file snake (Acrochordus granulatus) collected from marine populations in the Philippines and in Australia. File snakes dehydrate in seawater and do not drink seawater when dehydrated in air and offered seawater to drink. Dehydrated file snakes drink freshwater, and the threshold of dehydration for first drinking response is a deficit of -7.

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Temperature probably had no direct effect on the evolution of sea kraits within their center of origin, a geologically stable thermal zone straddling the equator, but may have indirectly affected expansions and contractions in distributions beyond that zone through global fluctuations that caused alternation of higher and lower sea levels. The northern limit of the Laticauda colubrina complex seems to be the 20°C isotherm; in the south, the range does not reach that isotherm because there is no land (also a habitat requirement of sea kraits) within the zone of suitable temperature. The relationship of temperature to the pattern of geographic variation in morphology supports either the hypothesis of peripheral convergence or the developmental hypothesis but does not distinguish between them.

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The direction of coiling was periodically recorded for two species of viperid snakes--copperheads (Agkistrodon contortrix) and cottonmouths (Agkistrodon piscivorus). Overall, neither species showed a significant preference for coiling in a particular direction. Only 1 of 22 snakes exhibited an individual preference, a result within expectation for random direction of coiling when using a 5% rejection level for statistical testing.

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Article Synopsis
  • The study examined the ultrastructure of pit organs and neuromasts in the skin of adult giant salamanders (Andrias davidianus) using transmission electron microscopy.
  • Neuromasts and pit organs exhibit differences in synapses, kinocilia arrangement, and the extent of separation between sensory cells and supporting cells, suggesting they have complementary functions.
  • The neuromasts in A. davidianus have unique features compared to other salamanders, including kinocilia orientation, supporting cell intrusion, thickened synaptic membranes, varied synaptic sphere distribution, and lack of a cupula.
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