Take the 2-minute tour ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

Does it exist any animal species that have two sexes and a kind of different internal diversification in two genders or more? I mean no something like different-task-based diversity but something biological? For example let's imagine a specie with:

  • 2 sexes (male and female)
  • 2 gender (A and B)

and individuals can match iff they are not only of different sex but also of different gender. So you can only have Ma-Fb, Mb-Fa.

share|improve this question
What sort of other classification are you thinking of? There are lots of different classifications, e.g. both male and female humans can have any of the four blood groups. Another example could be dogs (or a lot of other animal species) where another classification is race - each race has male and female dogs. –  Armatus May 11 '14 at 13:18
I would exclude those features because they don't determine directly the matching process (dogs don't match iff they are of different races, human beings don't if they are of different blood group). I've in mind some kind of upper-level biological feature, like sex is (different apparatus), that can influence sexual-selection. –  alessandro May 11 '14 at 19:19
You might find some things of interest with the search term 'alternative reproductive tactics'. –  Oreotrephes May 12 '14 at 19:32
Your definition isn't very good. For instance, a monolingual German speaker and a monolingual French speaker are extremely unlikely to "mate" in a conventional reality (in fact, there is even evidence somewhat supporting this). Obviously it's preposterous to call them "different genders", however. –  Superbest May 12 '14 at 19:38

3 Answers 3

Many organisms have multiple sexes. For instance, here is one which apparently has 7 (and each sex, or "mating type" can only mate with the others). The "gotcha" is that, mostly, they're unicellular organisms where mating in itself is weird to begin with. I haven't ever heard of a metazoan which truly has more than one sex (there may be variation within the males or females, but I think the sperms or eggs are always interchangeable).

Gender, I think, is more of a social term relevant to human behavior. Especially nowadays, so much of the literature and understanding of what is referred to as "gender" is closely linked to things such as gender identity, sexuality, gender roles and personality that is difficult to see how you could meaningfully speak about the "gender" of (non-human) animals.

It's analogous to the idea of "animal language" - certainly some animals may be said to behave in stereotypical ways which influence their mating behavior. Does that mean that what is written about human gender applies? I suspect precious little of it would. I would be quite skeptical of someone discussing gender (in the modern sense) for even uncivilized humans, let alone non-human animals.

share|improve this answer

Hermaphrodites and gender changing (M->F F->M) fish I have heard of. There are also occasionally individuals who are neither male or female, which may or may not count here.

But 3+ separate genders I haven't seen except for fungi, which might occasionally be multicellular, but probably not what you are thinking of. Fungal genders are so many because they define combinations where mating is compatible. This news story has a decent summary of why as far as gametes goes, larger animals are known to have only 2 gametic genders, while fungi can have thousands. You might say that bacteria have gender when they want it (when they have a pili-containing plasmid) and otherwise they have none - any individual may transfer DNA to another under the right conditions (like death).

I know this isn't what you are asking about, but this is the closest I can find... Digging around, biologist Joan Roughgarden has written a book "Evolution's Rainbow" about cases where there may be more than one social role in a given species for biologically male or females - dominance, display, homosexuality and behaviors like this. Social gender roles has been a way of talking about the biological nature of human social roles since the 1970s - see also Sarah Hrdy.

share|improve this answer
You're right when you say that social gender is the closest notion to what I might be looking for. A question: can a social gender of a certain individual change over time? If yes, I would exclude it from my research because I'm looking of something can't change naturally over time, as sex does. –  alessandro May 11 '14 at 19:23
I really believe the social gender can change over time - I think if you look around you will find lots of human examples. Its harder to decide for animals but I'd be surprised there were no supporting cases to be found. Animals including humans have this wonderful but slippery quality when it comes to their personality/identity - they can learn and change. Large changes in social environment can usually change us all a lot. For people you should look at the Big Five personality tests - might give you some ideas? –  shigeta May 12 '14 at 3:09
Are there any computational model of sexual reproduction? –  alessandro May 20 '14 at 8:15
too many to count. from cell division to population models. ask a question, but maybe think about what sort of model you'd like. pop = pop * 3.5 - deaths; is a population model. –  shigeta May 20 '14 at 12:43

I'm not sure what you mean by "gender" in the context of non-human organisms. Gender is usually defined as the intersection between biologically determined sex, and the surrounding culture.

Maybe you could argue that in social incests like, say, ants, the fertile queen and the infertile female workers diverge so much in behavior and gene expression that they aren't the same "sex", or that they could be considered different "genders", but I think that is really stretching the usual definitions of those terms.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.