Talk:Eusociality

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[edit] conflicting descriptions of eusociality?

The fifth paragraph (counting the numbered list of eusociality's "defining features" as second) allows eusociality as evolutionarily stable thanks to "superorganism theory," which is said to "make sense only when the sterile caste is physically sterile and not simply being repressed." At the end of the subsequent paragraph, in the discussion of eusociality in mammals, the claim is made that "some canids can [less rigorously] be argued to be eusocial, since only the alpha male and female will breed [... although] the other members of the pack are not sterile, but are dissuaded from breeding by aggressive behavior on the part of the breeding pair."

These are two contradictory claims that cannot both be true. Either eusociality is an altruistic function of a gestalt, wherein nonreproductive members are "physically sterile" and "not repressed"--and canids in their repressive, aggressive breeding-control behavior are something other than eusocial, "less rigorous" definition or not--or else eusociality is not strictly defined by the requirements of some sterility and non-repression, which would revert to the problem of "zero" fitness on the part of the nonreproductive members.

This is merely apparent on the surface; I have no depth in my understanding of the subject, so if anyone who knows can clarify this (both to me and for the sake of a consistant and clear article), please do.

GrammarGeek 02:01, 20 June 2006 (UTC)

[edit] Ug-lee

OK, this article was one big, ugly chunk of shapeless paragraphs and rambling technobabble.

I've made some attempt to improve its readability and clarity, hopefully this is a start. --Kaz 04:27, 12 July 2006 (UTC)

"Sisters are more related to each other than to their offspring" - sorry but the whole sisters / supersisters term needs a little more explanation. Aren't they sterile? DeadMansShoes (talk) 02:30, 18 February 2008 (UTC)

Not necessarily - many eusocial species have workers that are capable of reproducing. You have also, perhaps inadvertently, expressed why some researchers emphasize maternal control as an evolutionary driving force; if you give birth to sterile daughters, then they are compelled to become workers, since they no longer have the choice to reproduce themselves. Dyanega (talk) 19:34, 18 February 2008 (UTC)

[edit] Evolution as theory?

This article talks about various theories and how they relate to Eusociality, but then ends up stating evolution as matter-of-fact. It's still a theory, no matter how much you don't want it to be. EmeraldElement 05:42, 26 November 2006 (UTC)

Evolution is a scientific theory and carries a different meaning than the common usage. Human step 23:28, 17 January 2007 (UTC)

You are right. On the other hand the article does focus a little too much on evolution, IMO. Steve Dufour 00:26, 14 October 2007 (UTC)

Any scientific article that expects to be taken seriously should hardly waste time on criticizing evolution. It is a theory indeed, but it is widely accepted - on solid grounds - as the most probable one to date. This article would be quite incomplete without reference to evolution, and quite off-topic if it started questioning it. —Preceding unsigned comment added by 85.226.61.38 (talk) 10:45, 27 April 2008 (UTC)

[edit] Fictional Examples

"The Nac Mac Feegle, a Gnomish race in Terry Pratchett Discworld series, possess a eusocial culture, with hundreds of brothers begotten of one queen, called a kelda." Thats wrong, so I removed it. Eusociality is when they have sterile workers, none of the Nac Mac Feegle are sterile, and if they are, it is not mentioned. Aeti 02:24, 21 October 2006 (UTC)

I looked at the article for the Nac Mac Feegle and I think they might actually be a legitimate example, at least as far as imaginary creatures go. However, I've removed Borg, Zerg and Aparoid as they all seem to be parasitic, with every individual able to "reproduce", as it were. Also removed Tyranids as I can't find any information on their reproduction. Shayno 17:49, 13 May 2007 (UTC)
I realise the Nac Mac Feegle are hardly essential to the article, but while the books don't specify that any of the Feegle are sterile, they do state that only one of the males breeds with the kelda (her choice), while the rest fight and steal food. Does this make the Feegle eusocial? Among Naked Mole Rats all the rats are capable of having young, but many don't through stress. Is the situation with the Feegles comparable? Kaid100 (talk) 18:47, 1 February 2008 (UTC)

[edit] meerkats

Would meerkats count as an additional type of mammal in this catergory? Only the dominant meerkat matriarch is expected to breed but the other females are not sterile. They communally look after the young as well.

No, there is no sterile worker caste, therefore no eusociality by anyone's definition. To people who study eusocial insects, there are NO eusocial mammals, since even in mole rats the workers are not *irreversibly* sterile, the way they are in most sucoail insects. Dyanega 06:53, 16 September 2007 (UTC)
Still they should be mentioned, but with a disclaimer that they are not "true" eusocialites. Humans could also be mentioned since we often have non-reproducers helping raise their siblings' kids. Steve Dufour 00:24, 14 October 2007 (UTC)
It wasn't until the discovery of naked mole rats that ANY mammals ever even came close to being considered eusocial, including humans - there is a definition, one that's been in place for decades, and humans do not fit that definition. If you want to publish a NEW definition of eusociality, and write it so that humans qualify, and see how well it is accepted by the scientific community, then that might be a different matter. Dyanega 06:56, 14 October 2007 (UTC)
I am not suggesting changing the exact scientific definition. However it might add interest to the article if "eusocial tendencies" in humans and other mammals were mentioned, but only if a secondary source had said it first of course. (Please don't misunderstand this, but I think it would be worse if people quit reading the article out of boredom than if they were fed a little off-topic trivia to keep them interested -- or to help understand the concept. I don't pretend to be an expert on the subject however.) Steve Dufour 16:38, 14 October 2007 (UTC)

Given that overlap of generations and cooperative care of offspring (2 of the 3 defining criteria) occur in a vast number of living organisms, then - in that sense - there are many, many species with "eusocial tendencies". Realistically, the essential part of the definition, and the thing the article is intended to communicate, is just how important and unusual the "reproductive division of labor" aspect is. Eusociality is a very rare and peculiar phenomenon, in terms of the number of existing lineages that exhibit it, and perhaps only taken for granted because a few of the organisms that DO exhibit it are so familiar (ants, honey bees, termites); the bottom line, though, is that humans and virtually all other cooperatively-breeding mammals don't even come close to the sort of system seen in these insects. It may seem like it's just a technicality, but it's the kind of major technicality that makes for complete and unquestionable distinction between the things being compared - sort of like saying aside from humans not having wings, we have "flying tendencies" (which, in a very real sense, we DO - but not the sort of thing that would lead a biologist to classify humans as a species that is capable of flight). In that same way, whatever behaviors we may show that resemble those of eusocial species, we still could never classify humans AS eusocial. Even as the present definition stands, it is at odds with the original concept of the term, which was that "castes" were permanent, irreversible states - which is not true for naked mole rats, but is true for all other eusocial organisms. Rather than coin a new term describing the behavior of mole rats, the vertebrate biologists essentially did what I suggested earlier - they re-wrote the definition of eusociality so that they would be able to say that there was a mammal that was eusocial, and their arguments were persuasive enough that the point was effectively conceded (though there is still some debate - a lot of the utility in the categorization of social behaviors ultimately comes down to what sorts of questions you're asking, and for some of those questions, it's useful to consider mole rats as eusocial, but not for all such questions). Dyanega 19:46, 14 October 2007 (UTC)

Thank you. I came to this article because it is linked from the first sentence of Ant, which I was working on. I still think this article could be a little more friendly to the average person who doesn't know anything about the concept. Steve Dufour 15:10, 15 October 2007 (UTC)

"2 of the 3 defining criteria" it seems they meet all three with the current definition - "reproductive division of labor (with or without sterile castes) " DeadMansShoes (talk) 02:35, 18 February 2008 (UTC)

There is no species on earth where every single female has exactly the same number of offspring. Literally, then, EVERY species on earth has a "reproductive division of labor". Obviously, one cannot interpret "reproductive division of labor" to mean simply that some females have more offspring than others. It was implicit in the original usage of the phrase that this meant there were qualitatively different classes of females, one of which had a characteristic and qualitatively different level of reproductive output; the qualifier is that obligate sterility is not necessary, but that even if not, the less-reproductive class of females is a well-defined class. This is true for mole rats (which is why the point was conceded), but is NOT true for humans or any other vertebrates. This concept has been expanded upon in the elaboration of "skew theory". Dyanega (talk) 19:30, 18 February 2008 (UTC)