Article Abstract:
The bird evolution in the Paleogene is studied by describing the changes in climate that took place during the Eocene and early Oligocene across Europe and the lowermost Eocene Fur Formation of Denmark. The phylogenetic assessment of the Fur bird fossils are critical for future calibration of the neornithine evolutionary timescale and some early diverging clades are clearly present in the Paleocene as evidenced directly by new fossil material alongside the phylogenetically constrained Lower Eocene taxa.
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Article Abstract:
The ultimate, adaptive basis are integrated with the proximate, mechanistic bases for variation in reproductive effort in birds, particularly altricial species. The studies on the American kestrel and other species suggest that the seasonal increase in plasma concentrations of prolactin might regulate both a seasonal advance in the timing of incubation onset and a seasonal increase in the rate of yolk androgen deposition.
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Article Abstract:
The behavioural studies on thermal avoidance and preference and on the effects of temperature on motor activity indicate that the thermosensitivity of crustaceans is in the range 0.2-2 degree Celsius. Work on planktonic crustaceans suggests that they respond to changes in temperature by klinokinesis and orthokinesis.
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