Can Animals Be Gay?

A long but quite informative article on the subject: http://www.nytimes.com/2010/04/04/ma...pagewanted=all

Fascinating. Thanks for sharing. JR

This is an interesting behavioural ecology subject. Thanks for posting the link Axel.

First to the title, to which my initial reaction was, "yes, of course". The primate species called human, Homo sapiens, is an animal, some humans are gay, ergo an emphatic "Yes" to the question posed in the title "Can animals be gay?" As a biologist I always react negatively to statements like "animals and humans" as if these were two exclusive categories. They are not of course. It's like saying "penguins and birds", which incidentally I hear quite a bit in Antarctica!

The main problem with the article is that it implies that the albatross work on female-female (F-F) pairs is somehow novel and sheds new light on the sexual behaviour of animals in general. Seabird biologists have known about and understood female-female pairs since the late 1970s when the first of several papers came out on Western Gulls. Since that time numerous papers have been published on the subject showing that the phenomenon of F-F pairing occurs in special situations in an array of species, albatrosses being only one of them.

The "special situations" I refer to are when there is a skewed sex ratio in population with more females than males. This can occur for many reasons. In a recent paper I reviewed for a science journal, the authors found a complete lack of males in a small, isolated population of terns after a hurricane had wiped them all out the year before. The reason females were not affected was that they had already left the area when the hurricane came through (males stay behind to in the latter stages of the chick development period to finish off the young). The year following the hurricane, the incidence of F-F pairing was very high and only declined when males started to recruit into the population from elsewhere. F-F pairing "works" for females in situations where 1. there is a shortage of males in the population, 2. both parents are needed to incubate the eggs and raise the chicks successfully, 3. there is a chance of obtaining matings from males. As mentioned, it is quite common in seabirds because colonial breeding makes it easier to obtain matings from nearby males, and two parents are required for successful breeding in almost all seabirds.

However, the F-F pairing strategy does not work very well in evolutionary terms compared to male-female pairings. First, heterosexual pairs copulate many times a day. One reason is to be sure the eggs are fertilised. It is very hard for females in F-F pairs to obtain copulations at this high rate so we often find high levels of infertility in eggs laid by F-F pairs. Second, a female seabird tends to have as many brood patches as there are eggs in a typical clutch eggs; each egg has a place under the lower breast of the bird where it can be in contact with the bare skin of the parent and be incubated. As mentioned in the article, a tell-tail sign of a F-F pair is a very large clutch of eggs, say 5 or 6 in a species that typically lays 2 or 3. The obvious reason is that both females lay in the same nest. Therefore, eggs in a "super-normal" clutch are not incubated properly because each female has too few brood patches to incubate them all at once. Another problem is that the nest itself is designed to hold a normal-sized clutch so eggs in a super-normal clutch tend to spill out over the edges of the nest and are lost. All this means that the breeding success of F-F pairs of seabirds is usually far below that of a M-F pair. In populations of monogamous species where there is a balance of males and females, the F-F pair strategy hugely loses out to the M-F pair strategy. It only works when there is a shortage of males in a population to a point where the breeding success of F-F pairs is better than not breeding at all.

The article did not mention (as far as I could see) that male-male pairs of seabirds do not form when there is a shortage of females in the population. The reasons are obvious- M-M pairs would somehow have to coax females to mate with them and then lay their eggs in the M-M pair's nest. This is a highly unlikely scenario. In populations where females are limited, the best strategy for a male is to try to "steal" copulations from paired females in the colony, rather than to pair with another male. Thus, again, you can see that F-F pairing is a very special reaction to a skewed sex ratio, which doesn't work for males in the reverse situation because of the basic asymmetries between males and females (actually related to the relative size of gametes produced).

By the way, the inclusion in this article on F-F pairing in albatrosses, of discussion about homosexual behaviour in animals other than humans, "reversed" sexual behaviour, and the like, is a red-herring. The evolutionary explanations for these behaviours are entirely different than that for F-F pairing and should not have been presented as if they were somehow a continuum in the article's theme of "gayness" in animals.

Although thought-provoking, overall, I'd only give the NY Times a 5/10 for this attempt at improving the public understanding of science.

Thanks for your insight, John! This fills several gaps in the article. The title is probably deliberately provocative by asking if it makes sense at all to describe f-f and m-m breeding pairs as gay.

Since biologists seem to look for evolutionary benefits when explaining behavior, I am still wondering how to explain that f-f albatross pairs only raise one chick and don't seem to know/care whose egg it is. In this case, is it just about successfully raising 'a' chick?

Very interesting.
This book is one of the few on the subject:

http://www.amazon.com/Biological-Exuberance-Homosexuality-Natural-Diversity/dp/0312192398

Parts can be also found on Google books.