Female maternal relatives of gay men have higher fecundity, thus providing a genetic mechanism for the inclusive fitness hypothesis. See the work of Andrea Camperio Ciani and others: for example: Factors associated with higher fecundity in female maternal relatives of homosexual men. The Journal of Sexual Medicine 2012.
>________________________________ > From: "Culliney, Thomas W - APHIS" <thomas.w.culli...@aphis.usda.gov> >To: ECOLOG-L@LISTSERV.UMD.EDU >Sent: Thursday, March 28, 2013 1:07 PM >Subject: Re: [ECOLOG-L] Exclusive homosexuality > >Not every trait need be for some purpose (i.e., an adaptation). Human >sexuality is complex, and homosexuality is a facet of it. Perhaps it has >something to do with the fact that humans are sexually receptive at all times >and engage in sex not only for procreation, but also for recreation. > >Tom Culliney > > >-----Original Message----- >From: Mitch Cruzan [mailto:cru...@pdx.edu] >Sent: Thursday, March 28, 2013 12:31 PM >To: Culliney, Thomas W - APHIS >Cc: ECOLOG-L@LISTSERV.UMD.EDU >Subject: Re: [ECOLOG-L] Exclusive homosexuality > > >This neglects that fact that homosexuality is not an accident of history or >just a artifact of modern human societies. This trait is too widespread and >occurs at too high a frequency in human populations to be explained by chance >- there must have been a selective advantage in the past. The widespread >nature of this trait across human populations suggests that it must have been >present in the human lineage by at least the time of the second major >migration of hominids out of Africa around >60,000 ybp. The inclusive fitness argument mentioned several times by >contributors to this listserve is probably the best explanation for the >maintenance of homosexuality in human populations. > >Mitch Cruzan > >On 3/28/2013 7:46 AM, Culliney, Thomas W - APHIS wrote: >> I was referring to strict homosexuality in humans. Granted, there probably >> are cases in which children of a (perhaps deceased) sibling or other close >> relative would be raised by a homosexual, thus raising his or her inclusive >> fitness, but such cases would be rare. The Darwinian fitness of a strict >> homosexual is, as a rule, zero. Helpers at the nest do forgo their own >> reproduction to help relatives raise offspring, but, as far as I know, there >> is no requirement for them to be homosexual. >> >> Tom Culliney >> >> From: Jonathan Colburn [mailto:col...@gmail.com] >> Sent: Thursday, March 28, 2013 10:05 AM >> To: Culliney, Thomas W - APHIS >> Subject: Re: [ECOLOG-L] Exclusive homosexuality >> >> >> Hi Tom, >> >> Respectfully, the Darwinian fitness sounds like inclusive fitness, which is >> often measured by reproductive success. However, reproductive success of a >> homosexual is not always a good measure of their inclusive fitness (e.g. >> helpers at the nest). Ultimately, any action that staves off fixation of >> alleles to zero is about as close as we can come to determining that >> something is inclusively fit... >> On Mar 28, 2013 9:20 AM, "Culliney, Thomas W - APHIS" >> <thomas.w.culli...@aphis.usda.gov<mailto:thomas.w.culli...@aphis.usda.gov>> >> wrote: >> I note that the albatross article mentioned the words "natural" and >> "normal." Homosexuality certainly is natural, as it occurs in nature, in >> animals from groups ranging from arthropods to mammals (who knows what goes >> on in the plant kingdom?). In all cases, there appears to be an adaptive >> reason for the behavior. However, in its reproductive consequences, >> exclusive or strict homosexuality, as exhibited in humans, cannot be >> considered normal sexual behavior. The Darwinian fitness of homosexuals is >> zero. To the extent that there is a genetic component to the behavior in >> humans, with their diverse sexuality, the trait undoubtedly persists in the >> population largely through the actions of bisexual individuals leading to >> the production of offspring. >> >> The above is an argument strictly from a biological perspective, and is not >> a moral judgment. What two consenting adults do in private is their own >> business and no one else's. >> >> Tom Culliney >> >> -----Original Message----- >> From: Ecological Society of America: grants, jobs, news >> [mailto:ECOLOG-L@LISTSERV.UMD.EDU<mailto:ECOLOG-L@LISTSERV.UMD.EDU>] >> On Behalf Of Kristen Dybala >> Sent: Wednesday, March 27, 2013 10:55 PM >> To: ECOLOG-L@LISTSERV.UMD.EDU<mailto:ECOLOG-L@LISTSERV.UMD.EDU> >> Subject: Re: [ECOLOG-L] Expedition notice and question >> >> Laysan albatrosses are a fairly well-known example. Here's a (lengthy) >> article describing it: >> http://www.nytimes.com/2010/04/04/magazine/04animals-t.html?pagewanted >> =all >> >> -Kristen >> >> >> On Wed, Mar 27, 2013 at 6:53 PM, Merav Vonshak >> <merav...@gmail.com<mailto:merav...@gmail.com>> wrote: >> >>> This story reminds me of a similar story - a male pair of Griffon >>> vultures (Gyps fulvus). They incubated eggs and reared other pairs' >>> youngs as part of a breeding in captivity effort in Israel some years ago. >>> Merav >>> >>> Merav Vonshak >>> Postdoctoral Fellow >>> Gordon Laboratory >>> Department of Biology >>> Stanford University >>> Stanford, CA 94305-5020 >>> >>> Phone: 650-725-6791<tel:650-725-6791> >>> email: mvons...@stanford.edu<mailto:mvons...@stanford.edu> >>> http://www.stanford.edu/~mvonshak >>> >>> On 27, Mar2013, at 12:08 PM, Montblanc, Genie wrote: >>> >>>> WT, >>>> >>>> Since I don't study this, I'm giving a, "What I've heard in the news," >>> response. There were two stories awhile back, both relating to >>> animals in captivity, about homosexual pair bonding. One was with >>> penguins, I think they also raised a chick together, and the other >>> was with dolphins. Given that long-term pair bonding only occurs in >>> 8-11 species in the entire animal kingdom, the question might be moot >>> anyway. >>>> That is my inexpert response. Have a great expedition! >>>> Génie >>>> >>>> Eugénie MontBlanc >>>> Great Basin Fire Science Delivery Coordinator University of >>>> Nevada/Mail Stop 0186, Reno, NV 89557 >>>> Phone: 775-784-1107<tel:775-784-1107> (Fax: -1109) >>>> Email: e...@cabnr.unr.edu<mailto:e...@cabnr.unr.edu> >>>> Web: www.gbfiresci.org<http://www.gbfiresci.org/> >>>> Twitter: @GBfirescience >>>> >>>> -----Original Message----- >>>> From: Ecological Society of America: grants, jobs, news [mailto: >>> ECOLOG-L@LISTSERV.UMD.EDU<mailto:ECOLOG-L@LISTSERV.UMD.EDU>] On >>> Behalf Of Wayne Tyson >>>> Sent: Wednesday, March 27, 2013 10:32 AM >>>> To: ECOLOG-L@LISTSERV.UMD.EDU<mailto:ECOLOG-L@LISTSERV.UMD.EDU> >>>> Subject: [ECOLOG-L] Expedition notice and question >>>> >>>> [NOTE:] I will be on expedition (with a stop at the National Native >>>> Seed >>> Conference in Santa Fe NM on April 10) until the two weeks at the end >>> of April and the first week of May, then gone again beginning the 2nd >>> week of May until around May 24. I will not be checking email during >>> those periods, but will respond to as many email messages as possible >>> during those hiatuses. A third expedition following those is likely, >>> but the period of hiatus is iffy.] >>>> Here is my parting question. Please feel free to post it on other lists. >>>> >>>> Re: Homosexuality in animals other than Homo sapiens. We know that >>> homosexual behavior occurs in other species in some forms (Bonobo >>> chimpanzees [Pan paniscus], for example), and we know that >>> hermaphrodites of some species fertilize each other simultaneously. >>> But my question is in which species other than humans, does EXCLUSIVE >>> homosexuality, especially in the form of pair bonds, occur? >>>> WT >>>> >>>> I'll pick up my answers in late April. If I have time, I may be able >>>> to >>> respond to some today. Please respond on-list, and not to me personally. >>> >> >> >> -- >> ---------------------------------------------------------- >> Kristen Dybala, Post-doctoral Researcher Museum of Wildlife and Fish >> Biology University of California, Davis >> kedyb...@ucdavis.edu<mailto:kedyb...@ucdavis.edu> >> (415) 218-9295<tel:%28415%29%20218-9295> - cell >> >> >> >> >> >> This electronic message contains information generated by the USDA solely >> for the intended recipients. Any unauthorized interception of this message >> or the use or disclosure of the information it contains may violate the law >> and subject the violator to civil or criminal penalties. If you believe you >> have received this message in error, please notify the sender and delete the >> email immediately. > > >