And there are groups (like oribatid mites) where parthenogenesis is very common. No sex at all, though males occur. (Here's a challenge: you think of anything common among vertebrates, then look for invertebrates (including single-cellular animals) for whom it's not common. The sea-dwellers are very good for this search.)
Some people would tell you that only Homo sapiens exists as a species. Suppose a 'species' exists as a set of disjointed populations, which will never meet each other (or the probability of it happening is so much smaller than of them going extinct)...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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