Humans can be distinguished from other living apes by a
strikingly enlarged brain, reduced hair coverage on most parts
of the body, and by a suite of skeletal and muscular adaptations
associated with habitual bipedal locomotion, including the loss
of the grasping ability of the foot. Humans are terrestrial
bipeds with a limited ability to swim and dive that must be
learned.  The species shows strong variation in body size and
proportions, and pigmentation, some of which can be related to
the wide range of environments in which Homo sapiens lives.
Humans exhibit moderate sexual dimorphism in body size.   Humans
are opportunistic omnivores, showing remarkable ingenuity in
extracting, producing, processing and preserving foods. Humans
are the only species that can control or make fire, and cooking
is practiced by all known extant human groups.  Regional
variations in diet are influenced by availability within a
particular environment, by cultural traditions such as food
preferences and avoidances, and even genet