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Size and heat
Professor Brian Cox explores the relationship between an organism’s body size and its metabolic rate. He explains that smaller animals have a larger surface to volume ratio compared to larger animals. This means they lose heat at a much quicker rate. To combat this, smaller animals are forced to maintain a high metabolic rate, to keep a constant body temperature; their heart beats at a faster pace and they breathe much quicker, as such smaller animals do not tend to live as long.
Duration:
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