BIOL3045 Lecture Notes - Lecture 16: Vasoconstriction, Homeostasis
3 Jul 2018
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Animal Ecological Physiology BIOL3045 460381099
Lecture 16: Temperature dependence.
Endotherms have very sophisticated mechanisms to cope with temperature. Occur at the level of
maintaining homeostasis. Example: Goosebumps, vasoconstriction, shaking.
Other endotherms may undergo hibernation, decreasing heartbeat and temperature, to live off the
fat they gained form the feeding season.
Burgmann’s rule: looking within different populations, there is a tendency for organisms to get
bigger as latitude (colder) increases. Allows for insulation of body more, more mass less surface,
maintaining better constant body temperature. This is also observed for ectotherms. Developmental
rates are also faster in the warmer temperatures. This also corresponds with egg size: species that
live in hot climates have smaller eggs, those in the cold have larger eggs.
b0 = f(T)
When b0 vs temp, there’s an exponential increase.
Boltzmann and Arrhenius distribution of temperature dependence.
Effects of size and temperature on metabolic rate:
Intrinsic population growth predictably goes down with increasing environmental temperature.
This is important due to global warming, heterogeneous how temperature is changing all over the
world. More smaller species as the temperature is increasing. Populations are becoming younger.
Individuals are maturing faster.
Declining body size, response to warming? How will these things respond to gradual increases in
temperature over time? Don’t know how acclimation will affect this.
Document Summary
Endotherms have very sophisticated mechanisms to cope with temperature. Other endotherms may undergo hibernation, decreasing heartbeat and temperature, to live off the fat they gained form the feeding season. Burg(cid:373)a(cid:374)(cid:374)"s rule: looki(cid:374)g (cid:449)ithi(cid:374) differe(cid:374)t populatio(cid:374)s, there is a te(cid:374)de(cid:374)(cid:272)(cid:455) for orga(cid:374)is(cid:373)s to get bigger as latitude (colder) increases. Allows for insulation of body more, more mass less surface, maintaining better constant body temperature. Developmental rates are also faster in the warmer temperatures. This also corresponds with egg size: species that live in hot climates have smaller eggs, those in the cold have larger eggs. b0 = f(t) Whe(cid:374) (cid:271)0 (cid:448)s te(cid:373)p, there"s a(cid:374) e(cid:454)po(cid:374)e(cid:374)tial i(cid:374)(cid:272)rease. Effects of size and temperature on metabolic rate: Intrinsic population growth predictably goes down with increasing environmental temperature. This is important due to global warming, heterogeneous how temperature is changing all over the world. More smaller species as the temperature is increasing.
