The sex that invests the least has time to spare to seek other mates. Therefore, broadly speaking, males invest less and seek quantity of mates, whil… - Matt Ridley

Human beings are of course unique. They have, perched between their ears, the most complicated biological machine on the planet. But complexity is not everything, and it is not the goal of evolution. Every species on the planet is unique. Uniqueness is a commodity in oversupply.

Progress and success are always relative. When the land was unoccupied by animals, the first amphibian to emerge from the sea could get away with being slow, lumbering, and fish-like, for it had no enemies and no competitors. But if a fish were to take to the land today, it would be gobbled up by a passing fox as surely as a Mongol horde would be wiped out by machine guns. In history and in evolution, progress is always a futile, Sisyphean struggle to stay in the same relative place by getting ever better at things.

In behavior, as in appearance, every human individual is unique.