RANGE OF TEMPERATURE TOLERANCE ByDr P B Sirsat
RANGE OF TEMPERATURE TOLERANCE By-Dr. P. B. Sirsat Assist. Professor in Zoology, B. SC. T. Y.
RANGE OF TEMPERATURE TOLERANCE ØLife in this universe exists within a range of -200 to 1000 c. Ø Normal life persists within narrow temperature limits of about -10 to +500 c. Ø Many nematodes, rotifers & tardigrades have shown to with stand cooling to-2720 c with out ill effect. Ø Some algae & Bacteria are reported to live in the hot spring at 800 c. at temperatures greater than 900 c (BOTT & BROCK, 1969).
ØThe organisms (Microbes, Plants & Animals) which can tolerate very large fluctuations in temperature are called as eurythermal organisms. ØFor example, Cyclops, toad, wall lizards, grass snakes, man, etc. , are eurythermal animals.
ØThe organisms which can tolerate only a small variation in temperature are termed as stenothermal organisms.
ØThe common stenothermal organisms are fishes, snails, coral reefs, etc. In organisms all metabolic processes necessary for life start at a certain minimum temperature & increase with rise in temperature
Øuntil they reach the maximum temperature called as optimum temperature. The temperature range for any particular species is determined by the prevailing temperature of which normal physiological activities of the animals take place, as in distribution of the rotifer keratella procura (Nayer, 1970).
ØThis rotifer species is known to appear in the ponds of pilani, Rajasthan (India). If the temperature is below 240 c & to disappear when it rises above 240 c. The frequency of distribution reaching a peak during months October to March, with the fall in temperature.
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