Not a surprising result given that complex sea life significantly predates complex land life. It's had much longer to genetically diversify.

Similarly either we are all black, or black as a genetic race doesn't exist. The genetic diversity within humans in Africa exceeds the diversity outside of it. You can find two "black" Africans that are more genetically different than an Australian aborigine compared to a red headed Irishman.

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IAmBroom 6 days ago | parent [-]

Not sure of that last claim, as Australian natives are (AFAIK) considered one of the very oldest groups to separate from other Homo sapiens. IIRC, they're the only major group that has no Neanderthal DNA, because they migrated/were separated before H. sapiens met H. neanderthalis.

	▲	bryanlarsen 6 days ago \| parent [-]
		There are lineages in Africa that split from other lineages in Africa before the Australian aborigine split. Add on more frequent (but still rare) mixing for even more diversity. Mixing makes the majority more homogeneous but can increase diversity at the extremes.