Science Buddies: "Ask an Expert"

Hello!

My name is Zamira. Earlier this year, my biology teacher taught us about sexual versus asexual reproduction (rather standard, for a biology class). Alas, despite having learned this same subject in both seventh and eighth grade, it only then struck me that every definition I'd been provided had acknowledged the fact that sexual reproduction required more than one organism, but none had said it required two. And so, I was wondering: are there any species that require more than two organisms to reproduce?

(I apologize if this is out of place on this forum, considering it's not for a science project; I did check for other sources, but it seems my question is a bit too esoteric, even for Google. Thank you in advance for any insight you can provide.)

Hello Zamira,

Excellent question! In general, sexual reproduction is only done with two organisms. However, there is some research coming out that genetic contributions can be made by more than two organisms. For example, in the case of a surrogate mother (an egg is fertilized in a laboratory and placed in the womb of an unrelated mother), it has been demonstrated that some genes from the unrelated mother can transfer into the fetus, resulting in the baby having essentially three genetic parents (the biological father, the biological mother, and the surrogate mother).

In nature, however, sexual reproduction is only between two organisms.