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Why aren’t humans covered in hair like other primates are? (continued)

Paul Seedhouse
Newcastle upon Tyne, UK

In his answer to this question, Anthony Woodward dismisses the idea that hairlessness enabled hominins to hunt down animals on the savannah without overheating, but he makes the mistake of assuming that speed is the only effective hunting strategy available. All successful predators play to their evolutionary advantages, and hairlessness in humans enabled persistence or endurance hunting on the savannah.

David Attenborough suggests that this may be the most ancient human hunting strategy and that it could have been conducted even before weapons were developed. His film of a human running a Kudu antelope to death over 8 hours can be watched on .

Attenborough suggests that humans have the advantage that they can cool themselves by sweating from their pores and carrying water, and that running on two feet over long enough distances is more efficient than running on four feet.

Woodward notes that cheetahs can run at 110 kilometres per hour, but the downside is their lack of endurance, partly caused by rapid overheating due to their thick coat of hair. Hunts are usually limited to 300-metre sprints, after which cheetahs require up to 30 minutes to recover before eating or moving their prey, which is often stolen by other predators at this point.

It remains to be seen which predator remains around as a species for the longest.

Talia Morris
Cape Tribulation, Queensland, Australia

The answer to this one is simple: we are. Human skin has as many hair follicles per unit area as that of other primates, but because our body hair is much finer, it is less visible.

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