This habit has been bestowed upon them by nature since they cannot fight against predators in the forest. When it is not possible to save oneself through fight the best way is to lie quietly in one place so that the attention of hunters is not attracted.
A bird named poorwill is renowned for its long sleep. Every winter the poorwill hibernates for about 88 long days. During this long sleep its heartbeats lessen considerably and the temperature of its body also reduces. When winter is over and there is warmth in the atmosphere the poorwill wakes up automatically – as if an alarm bell has rung.
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