Showing posts with label Animal Sexuality. Show all posts
Showing posts with label Animal Sexuality. Show all posts

Monday, 9 January 2012

New Scientist: Fish that change sex – and back again

At  New Scientist, "Zoologger" has a post up on the transsexual abilities of the hawkfish (species Cirrhitichthys falco), which is found off Kuchino-Erabu Island in southern Japan. As the post notes, transitioning in fish occurs in many species - but this one reverses the process. (Even this ability is not unique though - see Joan Roughgarden, " Evolution's Rainbow ").


Transgender fish perform reverse sex flip

When it comes to selecting mates, hawkfish keep their options open. The flamboyantly coloured reef dwellers start life as females but can transform into males after maturing. Many marine animals do this, but these fickle fish have a rare trick up their fins: they can change back when the situation suits.

Tatsuru Kadota and colleagues from Hiroshima University in Higashi-Hiroshima, Japan, have observed reverse sex changes in wild hawkfish for the first time in the subtropical reefs around Kuchino-Erabu Island in southern Japan.

Hawkfish live in harems, with one dominant male mating with several females. Kadota's team studied 29 hawkfish and found that when it comes to sex change, the size of the harem matters.

If a male hawkfish took on many females, one of the two largest females would change sex and take over half of the harem, mating as a male. Conversely, if that new male hawkfish lost a few females to other harems and was challenged by a larger male, it reverted to mating as a female, instead of wasting precious energy fighting a losing battle. "The ability to undergo bidirectional sex change maximises an individual's reproductive value," Kadota says.

- read the full article at  Zoologger /New Scientist,06 January 2012 .

Footnote:

A reader, Mario, has shared a link to a fascinating story about a domestic hen that transitioned to a cockerel, after an injury. I've known about transitioning in fish species for years, but this is the first time I've come across an instance in birds.

Thanks, Mario.

Books:

Bagemihl, Bruce: Biological Exuberance: Animal Homosexuality and Natural Diversity

Roughgarden, Joan: Evolution's Rainbow: Diversity, Gender, and Sexuality in Nature and People,


 
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New Scientist: Fish that change sex - and back again

At  New Scientist, "Zoologger" has a post up on the transsexual abilities of the hawkfish (species Cirrhitichthys falco), which is found off Kuchino-Erabu Island in southern Japan. As the post notes, transitioning in fish occurs in many species - but this one reverses the process. (Even this ability is not unique though - see Joan Roughgarden, " Evolution's Rainbow"). 

Transgender fish perform reverse sex flip

When it comes to selecting mates, hawkfish keep their options open. The flamboyantly coloured reef dwellers start life as females but can transform into males after maturing. Many marine animals do this, but these fickle fish have a rare trick up their fins: they can change back when the situation suits.
Tatsuru Kadota and colleagues from Hiroshima University in Higashi-Hiroshima, Japan, have observed reverse sex changes in wild hawkfish for the first time in the subtropical reefs around Kuchino-Erabu Island in southern Japan.
Hawkfish live in harems, with one dominant male mating with several females. Kadota's team studied 29 hawkfish and found that when it comes to sex change, the size of the harem matters.
If a male hawkfish took on many females, one of the two largest females would change sex and take over half of the harem, mating as a male. Conversely, if that new male hawkfish lost a few females to other harems and was challenged by a larger male, it reverted to mating as a female, instead of wasting precious energy fighting a losing battle. "The ability to undergo bidirectional sex change maximises an individual's reproductive value," Kadota says.
- read the full article at Zoologger /New Scientist,06 January 2012 .
Books:


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Thursday, 29 September 2011

Tough Survivors: Gender Fluid, Intersex Eels

To rice farmers and agricultural economists, the rice paddy eel is a pest, presenting an indirect threat to rice crops. To me, it's yet another example of the remarkable gender and sexual diversity of the natural world - and one which is a real tough survivor.


REFLECTING nature’s remarkable diversity, the rice paddy eel is both hermaphrodite and transgender.
All the young start as females; some become masculine as they mature. When female densities are low, some of the male eels become transgender, turning into the opposite sex again.
The process, which takes up to a year, allows the replenishment of female populations. The greater the proportion of females in the eel population, the greater the reproduction rate.
This remarkable agility to adapt, and without natural predators, allows the paddy eel to multiply fast.
A rice paddy eel may grow as long as 3 feet to 4 feet and weigh as much as half a kilogram. As a voracious predator, its rapid spread threatens fishes, frogs, snails, worms and aquatic insects.
It survives harsh environments as well, from fresh and brackish to saline conditions and even cold temperatures well below freezing.
It can survive for weeks without food and, by burrowing in moist ground, can live for long periods without water.
When not using gills underwater, the rice paddy eel gets a fourth of its oxygen needs from the air – through the skin."

Wednesday, 21 September 2011

Bisexual squid 'can't tell mates apart' in dark waters - Telegraph

"An 18-year study of the Octopoteuthis deletron, a little-known squid which dwells a depth of 400 to 800m, found that males mate as often with their own gender as they do with females.
The difference between the sexes is so slight and meetings with fellow squid so rare that the amorous males are either unaware or unconcerned whether the object of their attention is female or not, US-based researchers said.
There is little light in the depths where the squid reside and the darkness of the water "cannot aid much in recognising potential mates," they added.
Writing in the Royal Society Biology Letters journal, the scientists said the squid only have a single, brief reproductive period during their short lifespan and will mate with any partner they meet during this time regardless of its gender."
-read more at The Telegraph
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Friday, 26 August 2011

Aquinas, "Nature" - and Sex.

Thomas Aquinas and Natural Law are often trotted out by the rule-book Catholics alongside the half-dozen clobber texts as a supposed justification for denying respect and equality to sexual minorities. I have absolutely no expertise in Thomist theology, but was intrigued by this observation, in a longer article ("The Other Side of the Catholic Tradition"), at the Washington Post.

Thomas Aquinas, who followed a century after Hildegard, wrote commentaries on 10 works by the greatest scientist of his day, Aristotle, even though the pope had forbidden Christians to study Aristotle. So controversial was Aquinas in his day that the king of France had to call out his troops to surround the convent where Aquinas lived to protect him from Christians aroused by fundamentalist clergy. For Aquinas, “revelation comes in two books—the Bible and Nature” and “a mistake about nature results in a mistake about God.” Aquinas insisted that one is always responsible to one’s conscience, more than to any other authority (emphasis added).

Lifting the lid on animal sex

 "In his new book Hung Like an Argentine Duck, Australian paleontologist Dr John Long aims to bring the weird and wonderful world of animal sexuality to the masses.
But there are also some interesting insights on human sexuality to be extrapolated from the book, challenging puritanical notions of what is ‘normal’ and ‘natural’: namely, that homosexuality is some kind of man-made choice, and that humans are the only species to indulge in sex for pleasure."

Indeed, once you’ve read Long’s passsages about dildo-wielding porcupines, bat blow jobs and necrophiliac snakes, you may be inclined to think we’re one of the tamer species in the animal kingdom.
“There isn’t any facet of human sexual behaviour that doesn’t already exist in the animal kingdom — the whole gamut of human sexual preference exists in animals in one form or another,” Long animatedly explained to the Star Observer.
“I must admit, a lot of it surprised me. We’re still learning new things all the time. I mention in the book that echidnas regularly have gangbangs, with five males to one female — that research was only published last year.”

In animals, [homosexuality] seems to be more about kinship and bonding, and how those animals fit in with a wider group or community, as opposed to a one-on-one pairing.”
In other words, those arguing that homosexuality is an evolutionary dead end are taking too narrow a view, with evidence that homosexual animals provide vital caring and support roles in animal communities, free from the burden of their own offspring.




'via Blog this'









Thursday, 25 August 2011

A Lesson in Couple Stability From Homosexual Zebra Finches

Is it possible for male couples to form lifelong, stable and faithful relationships?
Well, we know that some do - just look at the pics of couples lining up to tie the knot every time a new state or country introduces same-sex marriage or civil unions. These always show a high proportion of male and female couples who have been in stable relationships for several decades, eager to demonstrate to the world what they already know: that to all intents and purposes, they are really married de facto, and need to make that de jure as well.
We also know that as a group, gay men are statistically less likely than heterosexual married couples to form these life-long, stable and faithful partnerships. To confirm that, all we need to do is to consider the number of gay seniors who live alone, with the numbers who live with the same partner they have been with all their lives. The proportions are quite different to those applicable to straight men.
This is often used as a argument against gay relationships and LGBT equality. For example, in a nasty piece at the NOM sponsored Ruth institute, Jennifer Morse has this to say:
We already know that in terms of economic behavior, male couples are different from female couples, and both are different from married couples. We also know that separation rates (ie divorces) are different for male couples and for female couples and both are different (higher, like way higher) than for married couples.
(In a breathakingly inappropriate headline, Morse her article as "Intelligent Replies to Idiotic Comments", but I let that pass. Rob Tisinai at Box Turtle Bulletin does a great job of showing her "intelligent" replies are made to demolish straw men -supposed that the proponents of marriage do not, in fact, advance. Read it).
I want to respond only to the one part of Morse's piece which is not just a straw man response, but one which is dangerous and deceitful sleight-of-hand, the quote above. Let's look more closely at what she is doing, and then provide a response which, be great serendipity, comes to us from - the world of birds: homosexual zebra finches.
The problem with Morse's argument is that she is not comparing like with like.

"male couples are different from female couples, and both are different from married couples"
Not so. What she should have introduced into this statement, but could not do for her ideological bias, are the qualifiers "unmarried" (before "male couples"), and "heterosexual" (before "married). Then we would have the fairly obvious truism:

"unmarried male couples are different from female couples, and both are different from heterosexual married couples",
Conversely, we could also say,

"married male couples are different from female couples, and both are different from unmarried heterosexual  couples"
Would that statement be true? We don't know: married same-sex couples have not yet been around long enough to have produced compelling long-term evidence one way or the other. We do however have evidence to support another statement that Morse could have made - but did not:

"unmarried heterosexual couples are different from heterosexual married couples",
One of the arguments against cohabitation before marriage is the abundant evidence that these relationship dissolve more easily and more frequently than formal marriages, with the attendant problems that can ensue for all parties involved - particularly the children. All relationships take work to make them endure. The stresses that contribute to relationship breakdown can be hard to resist at any time without reinforcement. The public visibility of a formal marriage, the vows that the parties have made and the legal obstacles in the way of divorce, all provide those reinforcements. It is no wonder that cohabiting relationships (gay or straight) break down more rapidly than married ones (gay or straight).
In addition to the standard difficulties in maintaining any long term relationship, gay couples have additional stresses unique to them, which arise from public prejudice and homophobia. (Things like the challenges of dealing with being fully out, or negotiating partial closets, problems for some couples with family acceptance, for instance). The apparent instability of gay couples may have more to do with their social circumstances, than anything inherent in the homoerotic orientation. To get a meaningful like for like comparison, we should be comparing  unmarried gay couples with unmarried straights, in a context where neither is handicapped by homophobia or public pressure. In the human context, this possibility simply does not exist.
In the natural world it does. Many animal species exhibit same-sex bonding and long-term couple formation. The animal kingdom  shows even greater sexual and gender diversity than the human one - and anything comparable to homophobia appears to be unknown. Published studies of individual species have shown that these same-sex couples are as stable as the mixed-sex counterparts. By great serendipity, the BBC has reported on another of these, a recent report of research into homosexual zebra finches, which corroborates my hypothesis above: that in the absence of homophobia, male couples can endure every are every but as stable as any others.

Male pair of Zebra finches
Same-sex pairs of monogamous birds are just as attached and faithful to each other as those paired with a member of the opposite sex.
The insight comes from a study of zebra finches - highly vocal, colourful birds that sing to their mates, a performance thought to strengthen the pair's bond.
Scientists found that same-sex pairs of finches sang to and preened each other just like heterosexual pairs.
The study is reported in the journal Behavioural Ecology and Sociobiology.


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Tuesday, 7 December 2010

Breaking Up Is Hard To Do..... Also For Vultures

Same sex pair bonding is widespread, throughout the natural world. Zoos are not exactly the natural world. The animals live in unnaturally confined conditions, and are often maintained there for the specific purpose of boosting numbers, in formal breeding programs. Unless you have an objection in principle to the mere existence of zoos (I'm neutral on that one), it's difficult to get seriously dogmatic about the story Guido and Detlef, the male vultures of Munster zoo - but it does raise some questions:

The drama began in March when Guido and Detlef set up home together at the Allwetterzoo, in the British Army garrison town of Munster, northwest Germany.
The griffon vultures, Gyps fulvus, showed no interest in female company. They were happy in their own world, grooming one another with tender sweeps of their savage beaks between rearranging the sticks that made up their nest, although the other vultures kept stealing materials as if to spite their arrangement.
Dirk Wewers, the zoo's curator, said: "They always sat so closely together. They defended their nest from the other vultures. A suitable female was missing and in such a case vultures look for companionship from the next best thing, even if it is a male. Detlef looked for a bird of the opposite sex but settled with Guido."

Saturday, 31 July 2010

Bisexual Snails

There is a widespread myth out there that homoeroticism is somehow "against nature" because "animals don't do it".  The argument is deeply flawed on numerous counts:  Are we to model our behaviour on the animal kingdom? If so, why was the church for so long opposed to the male -behind heterosexual sexual position as ("animal like"), insisting instead on the completely unnatural missionary position? Why argue  that animals "Don't" do it", and simultaneously that it should be avoided because animals (the hare, the weasel, the hyena) DO "do it"?
The whole idea of "against nature" is a key part of the Christian church's development of opposition to same sex relationships, but is full of weaknesses in logic as well as empirically verifiable evidence.
I am in the midst of preparing a lengthy post demonstrating how flawed the argument is. In the meantime, by serendipity I have come across the following story in New Scientist magazine, on the omnisexual appetite of the rough snail. Remember, that logically a single counterexample is enough to demolish an argument such as "all animals avoid same sex activity." This counterexample eliminates that claim at a stroke. Other counterexamples, which I will present shortly, will demonstrate the more modest claim that exclusive heterosexuality is somehow "normal". What is abnormal, in the global context, is exclusive, compulsory heterosexuality .
Males track females by following their mucus trails, and will attempt to mate with pretty much any snail they encounter, regardless of whether it is the correct sex or even the same species. They mate with males just as often as they do with females – though they do give up such copulations sooner.

Wednesday, 28 July 2010

Same-Sex Parents, Furred and Feathered.

There have been an increasing number of research studies which show that as parents,  same sex couples are at least as good as opposite sex- couples. As a gay father and grandfather myself, I don’t really need to be told this by modern research: I first learnt of the evidence decades ago, from a family friend who was then a child welfare social worker, and is today a top authority on the subject. I also have the best of all possible authority, the experience of my own family. My daughter is very clear on the subject: she is on record as saying “Gay Parents? I recommend them”. She has told me that when she says a young child with two dads, her immediate response is - “Lucky child”. Still, it’s good to see the evidence getting a more public hearing. and reaching the mainstream.

I was interested though, to find that in this, as in so many other areas, of human sexuality, the same pattern is found in many species of animals and birds.

Two Dads, with Kids
Homosexuality in animals has been known since ancient times, but still fails to penetrate the public consciousness. Nevertheless, researchers are now starting to publicize the abundant evidence for same sex coupling, pair bonding, and parenting. (And contrary to the protestations of Focus on the Family, NOM, et al, these do not always go together, not in humans, not in animals.) The nature and variety of the forms that animal parenting can take is breathtaking, with all the variations found in human society, and more (some of the animal practices would land humans in jail. “Nature” is not all sweet and lovable).

How do same sex couples find their next generation? In many of the same ways humans do, but excluding the turkey baster and in vitro fertilization. Quite often, they were in the same position I was – offspring resulted from an earlier, opposite-sex partnership. For females, Laysan's Albatross and many other birds may use sperm donors, finding an obliging male to copulate with, for the sole purpose of fertilizing their eggs. Male couples may find surrogate mothers: Black Swan male couples may hook up with a female in a menage a trois – then boot her out after the eggs have been laid. Adoption is also common: many species have same sex couples that take on orphaned or lost youngsters. Some couples are rather more cavalier though, and simply kidnap their youngsters – quite literally, in this case. (Don’t try this if you’re human, though.) Just as in human society, some youngsters biological parents who either can’t or won’t raise them themselves – and they may dump them on same sex couples to raise, in nest parasitism.

Are they good parents? Quite often, not only as good, but better. There are many reasons for this. In birds, quite often it is not true that children “need” a mom and a pop. Many species (such as Warthogs, Red foxes and Sage Grouse) are raised by just one parent. When they get two parents, even of the same sex, that is immediately a bonus – they get double the parenting right off. Often, they get better, more spacious homes. Some female bird couples (Greater Rheas, Canada Geese) build what amount to double nests to hold two clutches – but where only one clutch has been fertilized, bingo: a double size home for a standard size family. Some male couples get bigger nests because only the male does the nest-building. Two males = two builders, and again, a bigger home. Other male couples get not so much a bigger home, as a bigger lot. Black Swans use their superior combined size and strength as two males to grab bigger or better territories – and thus better feeding grounds. Mammal youngsters sometimes get better feeding, simply by having to moms to nurse them: some females will suckle their partners’ young - grizzly bear mamma pairs may both nurse and protect each other's young. Then there are the family variations not usually seen in humans. If two parents are better than one, how about three, or even four? Grizzly bears are often raised by female pairs – and sometimes by female trio (The familiar term "gay bears" takes on a whole new meaning).

When sexual activity between males, or between females has been professionally observed, it has too frequently been dismissed or explained away as “deviant”, or the result of “accident”, or even as “immoral” behaviour (as in “A Note on an Apparent Lowering of Moral Standards in Lepidoptera”, the title of a published scientific paper. I kid you not.) In many parts of modern Western culture, there has arisen a deeply held assumption, in spite of all the evidence to the contrary, that the only "natural" form of sexuality and family is "one man, one woman". Even when faced with evidence to the contrary,from the animal world or from human anthropology and history, these people dismiss such evidence as "freakish", or unnatural. In their own observations, their hetero normative assumptions distort the evidence. When one animal is observed mounting another, it is simply assumed that the one on top is male, the other female. And so the myth is perpetuated that only opposite sex mounting occurs.

The plain truth is that in nature, sexual diversity is the norm. (It may well be that what is truly “unnatural” is exclusive heterosexuality . Fortunately, several writers over the last decade have begun to expose the way in which these biases have been distorting scientific research and its dissemination. We will be hearing a lot more about animal same sex relationships and parenting in future - which will help to counter the lies and ignorance propagated by the sexual morality brigade.

Also See:
Previous Posts at "Queering the Church"


Books:

Tuesday, 27 July 2010

Queer Bonobos: Sex As Conflict Resolution

In trying to understand "natural" sexuality, a look at the world of the bonobo is intriguing. Often loosely described as "chimps", bonobos are in fact a quite distinct species, closely allied to both chimps and to humans, and may in fact be the closest of all primates to humans in evolutionary development. In addition to physiological and genetic similarities, they also show some features of sexual behaviour that are unusual in animals - but familiar to humans. For example, females remain sexually receptive for far longer than other species. Instead of being physically ready for sex for just a few days in her cycle, the female bonobo is almost continuously sexually attractive and willing for sex. Intercourse is more frequent than in other primates, although the reproduction rate is similar: there is a partial separation between sex and reproduction. Mating is more often face to face, like humans, than in other animals, where the dog-like position is almost universal. Both males and females become sexually aroused remarkably easily. Oh, and there's a great deal of same sex activity. Frans De Waal, on whose research I base my notes,  says that the most typical sexual pattern is genital rubbing between females:
One female facing another clings with arms and legs to a partner that, standing on both hands and feet, lifts her off the ground. The two females then rub their genital swellings laterally together, emitting grins and squeals that probably reflect orgasmic experiences.
Males also engage in genital contact, including "penis- fencing", and rubbing the scrotum of one against the buttocks of another.
De Waal first became interested in bonobo behaviour not for its sexual component, but as part of a study into primate aggression. In continuous observations of bonobos in a zoo, he found that a standard feature of the behaviour was sexual arousal and intercourse immediately before feeding. As soon as a caretaker approached with food, the males would develop erections, and the animals would invite each other for sex. (This is not just an aberration of captivity. Other researchers have observed the same association between food and sex in the wild: after a group had entered trees with ripe fruit, or after they had killed a young prey animal, there would be a flurry of sexual contacts before settling down to eat.)
De Waal later found that it is not just food that leads to sexual arousal, but anything that gets the interest of more than one animal at a time - in other words, anything that could lead to competition. In the zoo environment, when two bonobos share an interest in a cardboard box thrown into the enclosure, they briefly mount each other before playing with the box.
In some aggressive contexts related to conflicts between animals, there will often be genital contact to follow. Where one male drives another away from a female, the two males may later reunite for some mutual genital rubbing. Or if one female strikes a juvenile, its mother may lunge at the other female - but as with the males, this brief conflict will be followed by the two rubbing their genitals together.
De Waal thus concludes that sexual behaviour among bonobos is a mechanism to reduce conflict:
During reconciliations, bonobos use the same sexual repertoire as they do during feeding time. Based on an analysis of many such incidents, my study yielded the first solid evidence for sexual behavior as a mechanism to overcome aggression. Not that this function is absent in other animals--or in humans, for that matter--but the art of sexual reconciliation may well have reached its evolutionary peak in the bonobo. For these animals, sexual behavior is indistinguishable from social behaviour.
Sexual relationships are also used in a more positive way, to forge social bonds, particularly between the females. As with many animal species, bonobos live in clan groups. In their case, the males remain for life in their birth clans, so they will know all the other individuals. It is the female bonobos who leave, and start a new life as adults in a new clan, where they are strangers. They routinely approach one or two senior females, and attempt to establish a sexual relationship. If this is reciprocated, the association becomes permanent, with the older females acting as guardians to the younger. Later, as the newcomers themselves become established seniors within the clan, they may likewise accept sexual approaches from new female arrivals, and take on their guardianship.
Here we can point out that this use of sexual relationships to promote social bonding and avoid conflict has clear parallels in human society.  At the domestic level, the "kiss and make-up scenario" is well known, in which a quarrel between partners may be followed by particularly intense love-making. At a grander level, for many centuries of European history, formal marriage was usual only for the wealthy classes, to protect property and inheritance rights. At the highest social levels, dynastic marriages were frequently arranged to ensure political alliances between royal houses - and to reduce the risk of war. Elsewhere, other societies have used homosexual relationships between men in the same dynastic way, to promote cordial relationships between clans. This has been noted in medieval Egypt, and in China.
There is one other feature of bonobo sexuality that I found has a remarkable resemblance to some human practice. Freed from the tight connection between intercourse and reproduction,young and attractive bonobo females are able to use their charms for material gain.   Some females have been observed to approach males with an enticing food supply with clear a clearly sexual offer. After intercourse, the male will share his food with the female, who then leaves.
Females offering males sexual favours for profit: sound familiar?
Source:
de Waal, Frans B.M. : Bonobo Sex & Society, Scientific American, arch 1995, which I found on-line here
See also my previous post here at QTC:
Books: