Low temperature tolerance of insects in relation to the influence of temperature on muscle apyrase activity

Temperature acclimation in Tribolium confusum and Musca domestica: rate of acclimation measured at locomotory, metabolic and enzyme levels

“…It was also shown that the temperature coefficients were lower in the cold-acclimated insects. This is opposite to the relationship found in interspecific comparisons of insects (Mutchmor and Richards, 1961), but similar to the relationship, shown for other animals and processes by Bullock (1955), Presser (1958), and Precht (1958, Other workers using different muscles in individuals of a species, have also shown the temperature dependence of ATPases. Calaby (1952, 1953) found a greater activity in flight muscle than in the leg mus cle in the locust, Locusta migratoria.…”

“…These spe cies are examples of those insects that function at the extremes of the normal temperature range. Work by Mellanby (1939Mellanby ( , 1940, Colhoun (1954Colhoun ( , 1960 and Mutchmor and Richards (1961), with insects whose habitat tem peratures are well within the normal temperature range, has shown species differences with respect to functional capability at low temperatures. In general, they found that insects which normally encounter a wide range of temperatures have the lowest chill-coma temperatures.…”

“…Colhoun (1960), Mutchmor and Richards (1961), Thiessen and Mutchmor (1967), and Anderson and Mutchmor (1968) have shown that, if individuals of a spe cies are maintained at two different temperatures, the chill-coma temper ature of the insects exposed to the lower temperature may be as much as 5°C lower than that of insects which were maintained at a higher temper ature.…”

“…The highest temperature coefficient was obtained with the cockroach, the lowest with the minnow. Mutchmor and Richards (1961) established a relationship between temperature tolerance and ATPase activity among six species of insects, a crayfish, Cambarus diogenes. and the horseshoe crab, Limulus polyphemus.…”

“…Mutchmor and Richards (1961) acclimated the mealworm, Tenebrio molitor, to 35®C and 15*C and the cockroach, £, americana to 30, 10, or 15^C. Differences in chill-coma temperatures indicated that accli mation had occurred.…”