the earliest Homo sapiens had bodies with short, slender trunks and long limbs. These body proportions are an adaptation for surviving in tropical regions due to the greater proportion of skin surface available for cooling the body. More stocky builds gradually evolved when populations spread to cooler regions, as an adaptation that helped the body retain heat.
Modern humans now have an average height of about 160 centimetres in females and 175 centimetres in males.
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