Size variation and the distribution of hemimetabolous aquatic insects: two thermal equilibrium hypotheses

350 210 Stroud Water Research Center

Sweeney, B.W., and R.L. Vannote. 1978. Science 200(4340):444–446.

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Adult body size and fecundity of a number of hemimetabolous aquatic insects depend largely on thermal conditions during the larval period. Small adults and reduced fecundity result when temperatures are either warmed or cooled with respect to more optimal thermal conditions. Temperature apparently affects adult size by altering the larval growth rate and the timing and rate of adult tissue development for each larva. The data suggest a new interpretation for the geographic distribution of aquatic insects.


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