The species would be a great ape of a distinct genus, with human-like intelligence and inventive power. The members would only have one sex (either male or female), so that all individuals have the same reproductive anatomy. They reproduce around as often as a human, with the offspring being clones of the parent. The species would interact with other species with both male and female sexes and genders. Is it plausible that a species like this would retain both the male and female genders, or would one or both become unrecognisable as the binary genders due to the effects of genetic drift?
Is it plausible an asexual or Kleptogenic ape could retain both sexes?
No, it's not plausible, not really, not in apes.
Both asexual reproduction & unisexual Kleptogenic reproduction is achieved by all-female species & (if possible, I'm not sure there aren't barriers to either in apes) would produce female offspring.
In the Komodo dragon asexual reproduction can produce male offspring true but the problem for apes is the X & Y genes & that females are XX, Komodo dragons don't have the same sex gene set up as apes, in Komodo dragons the sex genes are W & Z with males being ZZ & females being WZ which allows them to produce male as well as female offspring.
A female ape couldn't produce a male only having XX to play with.
Having said that It is possible that they could have developed the reproductive strategy as a backup that sees use when there are no males of their own species available but with the females being XX it's more likely than not & always a danger that eventually the males just disappear entirely.
But, that said, that still leaves you with a pretty long time frame when the two reproductive strategies are coexisting, if they were as intelligent (or nearly so) as us & culturally want to preserve both sexes then that could be a pretty indefinite period of time.
If however you're asking in a rather awkward way if they could retain both gender roles assumed by different individuals of the same sex then yes, of course they could & to some degree the whip tail lizard demonstrates that at a basic level with one often mounting another in ersatz mating displays.
There's some evidence the 'mating' in whip tail lizards can help trigger ovulation & reproduction.
If simple hormonal triggers can be caused by 'mating' in a lizard then it's far from outrageous to suggest various instinctive & emotional factors in an ape that had become asexual might lead to more complex behaviours including the adoption of the missing gender by some of the population.
But this might be less likely in a Kleptogenic ape, more likely it would simply adopt the males of the other species into the male role in most instances, which of course doesn't preclude the full range of sexual identity currently found in humans* & only suggests the 'norm' of the species.
*aka anything & everything.
Not Likely, but Possible:
So I will operate on a couple of assumptions based on your comments.
- Your males somehow have the capacity to gestate young.
- The males and females have lost the capacity for sexual reproduction with each other.
- Fundamentally there is a question if a great ape could long-term survive without sexual reproduction and gene mixing. I will ignore that issue for this question, but it is central to your species and will need to be addressed somehow.
So ultimately your question is if the two genders would diverge as two separate species or stay bound as a single species with shared characteristics.
The same question can apply to every starting individual in the population. They no longer are bound to each other as they no longer mix genes. By some definitions, they are no longer a single species. Your "staying together" scenario is unlikely, but not impossible with enough pressure to remain together.
Given sufficient mutation and evolution, every "individual" in the starting population could give rise to a new species. Then every individual of each subgroup could give rise to a new species. They don't exchange genes and every mutation is a success or failure on its own.
But you could have selective pressure to maintain cohesion. If survival as a collective puts a premium on homogeneity, anyone different than the expected body plan and behavioral pattern is selected against, dies, and fails to reproduce. So as long as there is pressure for all individuals to resemble the original group, they will continue to do so. If there was a significant specialization by gender in the group, one gender might be incapable of survival without the other. At that point, your group dynamic would resemble symbiosis.
- One alternative to maintain cohesion is if there was still a mating requirement. The females gestate, but need to have sex to be primed to do so. When this happens, there is an equal chance that a bit of the male is cloned OR that the female undergoes parthenogenesis (or perhaps both happen and there are always "twins"). The female can't reproduce without the male, and the male can't reproduce without the female, yet no DNA is exchanged.
If the mutation is in a consistent direction, or there is an alternate means of gene exchange (say, some kind of virus), then you might even have evolution of the group in a common direction (for example, everyone gets taller because tall individuals keep doing well and eventually every group has a "tall" mutant that thrives).
Given these premises, certainly
We won't evaluate the likelihood of the kleptonic reproduction. But if they reproduce this way (or any other), then naturally they can have two or more genders. Gender is a social construct, after all, not dictated by any simple genetic means even in humans. If some activities were limited (even partially) to one gender role, then the population would actually need multiple genders to realize its full potential.