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Waveform Audio File Format  |  1995-06-29  |  382.5 KB  |  1 channel  |  22,050 sample rate  |  35 seconds  |  [TEXT/LMAN]
Transcription: Most animals are ectothermic, which means that their body temperature changes according to the outside temperature. Ectothermic animals are more active in the heat because chemical reactions inside cells work faster at higher temperatures. Animals behave in particular ways to control their body temperature. For example, lizards lie out on the rocks in the morning sun to gain heat. They burrow at night to conserve heat. Birds and mammals are able to maintain a constant high body temperature. Such animals are called endothermic.