How Can Hummingbirds Stay Warm?

     Hummingbirds are the smallest homeotherms, they suffer from low thermal inertia and high heat loss.  As a result of this, convective cooling due to wing and air movements further impedes thermoregulation in humming birds.   When temperature is lowered, the wingbeat kinematics of hummingbirds change.  Their frequency is increased, but the stroke amplitude decreases, this suggests there is a thermoregulatory role in Hummingbird flight muscles (Chai et al. 1998).  Research has shown that in hover feeding, oxygen consumption increases moderately between 35-5 degrees Celsius, but while perch feeding, it increases dramatically.  These results suggest that heat from the contraction of flight muscles substitutes for regulatory thermogenesis (Chai et al. 1997).

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This website was created for an assignment in Animal Physiology class at Davidson College.
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