The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Did you know?
Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.
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Approximately one in four people diagnosed with diabetes will develop foot problems. Of these, about one-third will require lower extremity amputation.
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In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
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The human body produces and destroys 15 million blood cells every second.
Disruptive selection.
Three principle forms of natural selection: (a) stabilizing selection, (b) directional selection, an
Coefficients of relatedness: How kin selection works.
An example of a selection list used to identify symptoms.