Jump to content

Asexual Animal?


an1malclawz

Recommended Posts

I'm not sure. They don't really do studies on that type of thing. I can really only think of animals that are biologically asexual, like whip-tailed lizards (there are no males of the species so females basically clone themselves but have to mime sex with other females to kick off the process).

There are some species where lower animals in the heirarchy have forced celebacy either by chemical retardation (like naked mole rats) or by force (wolves and merecats). But I'm not sure if there are any species that would not have sex when presented the opportunity. I think the more likely animals to show asexual tendencies are solitary animals rather than those that gather in groups, like tigers or pandas or leopards, etc.

Has anyone found anything?

Link to post
Share on other sites

I think there are asexual animals but it would be nearly impossible to find them. After all, we can find homosexual animals based on the fact that we catch them in the act. Even if we found an asexual animal, we would just assume that it either couldn't get a partner or just was not going to have sex for that round. Also since social mammals have to fight for the right to mate, an asexual animal would just never fight for it and let the more sexually aggressive ones go at it.

Anyway I figure asexual mammals would be rare. After all, without the urge to mate their genes would not pass on most likely. Well unless its a female asexual that is forced to mate. Even then though, I would have to question whether or not the animal would raise the offspring or even if the animal would become pregnant. Stressful situations, ie rape, tend to result in the body aborting the fetus.

Link to post
Share on other sites

There have been studies regarding asexual sheep, but I don't know if there is a link to it.

Also, there is book called "Zamba: The True Story of the Greatest Lion That Ever Lived," by Ralph Helfer. Ralph Helfer was an animal trainer who trained animals to work in movies. He trained Gentle Ben (the bear), Clarence the Cross-Eyed Lion, elephants, giraffes, orangutans... he had a lion named Zamba who starred in "Fluffy" with Tony Randall. Zamba was so tame he let his 7 year old daughter play with him. Ralph introduced many attractive lionesses to Zamba, but Zamba never seemed interested in the lionesses. He wanted Zamba to have cubs, but Zamba never fathered any cubs. Although there was a younger lion that Ralph worked with who looked a lot like Zamba and was named "Zamba Junior." Could Zamba have been an asexual lion? Perhaps that was why he was so tame -- because he did not have all the "anxiety" that most lions have.

Link to post
Share on other sites

I don't know about cats but I have three De-sexed cats and I have observed their behavior for many years now. One of my cats always humps the blankets in my house but the other two are uninterested in doing the same.

Link to post
Share on other sites
Here's one article talking about the study on rams, and how those uninterested in sex have the same hormone levels as those into ewes or other rams.
Link to post
Share on other sites

Can there be asexual animals?, we're kinda like animals, we're primates and we can be asexual.

I've heard that about 10% of rams show no inclination to mate, even when cooped up with ewes. I'm certain that animals can be asexual, just as people can.

E.

Link to post
Share on other sites
you*hear*but*do*you*listen

I'm pretty sure my cat is ace. :P

Link to post
Share on other sites

I'm pretty sure my cat is ace. :P

Me too. She's a repulsed aromantic asexual, also; won't let any other cat get near her.

Link to post
Share on other sites

I've read an article somewhere before saying how there seemed to be asexuality in animals. They presented it as a surprising discovery, but it didn't really surprise me much. I've always thought that if asexuality can exist in humans, there's no reason why it can't also exist in other species.

Link to post
Share on other sites

In any gregarious social animal, there is a hierarchy in the group largely centred around sexuality. I would venture to suggest that SOME "subordinate" animals of social species (eg. wolves, lions, meerkats, great apes) are to some degree asexual. They don't particularly contest the alpha animals because they don't particularly care if they get to mate or not.

Followed to its extension, I'd say that I'm arguing that asexuality in social animals serves an important, cohesive function for the group when reproduction amongst all animals is not possible. There is always a need for caretakers and hunters and watchmen, and all of these activities are difficult to engage in if you're constantly trying to get laid or move up the sexual hierarchy.

Link to post
Share on other sites
Most of what is known about asexuality is really an educated guess or supposition; otherwise there would be some way to respond to the skeptics. So what research has been done on asexuality? There are several recorded instances of animals that refuse to mate, such as lab rats. A study on Mongolian gerbils showed that part of a population of male gerbil fetuses that developed between two female fetuses refused to mate, but instead spent almost 50% more time taking care of the young than male gerbils who as fetuses were positioned between two other males. They were also about 30% more likely to stay with a nest when the mother had left. This suggests that, although not perpetuating their own genes, they helped perpetuate their sisters' genes, which has evolution benefits for at least half that family's genes. These "asexual" male gerbils had on average half the level of circulating testosterone and 50% smaller bulbocavernosus muscles compared to the gerbils who had been between two males as fetuses. As male gerbils become violent when placed together, there was no way to tell if these asexual gerbils weren't actually homosexual instead, but the study still indicates that there are mammals that refuse to reproduce due to natal conditions. (8) Another study done on rams showed that besides the population of rams readily willing to mate with females, there was also a subset of rams who mounted other rams, and another subset that refused to mate at all. The asexual rams had testosterone levels comparable with those of the heterosexual rams, exogenous testosterone treatments did not prompt them to mate, and so the researchers concluded neither hypogonadism nor basal androgen concentrations caused the rams to exhibit asexual behaviors. However, when anesthetized, the homosexual and asexual rams had higher levels of cortisol concentration than the heterosexual ones. The researchers noted, "the endocrine response to anesthesia is most likely mediated through the central nervous system, the present results indicate that functional differences exist between the brains of rams that differ in sexual behavior expression and partner preference." (9) Since scientists have already noted that the brain of homosexual men is structurally different from that of heterosexual men (cell structure of gay mens' hypothalamus more closely resembles that of a heterosexual female's), that the asexual brain may too be structurally different should not be too easily dismissed. The existence of animal displays of asexuality run contradictory any suggestions that asexuality is a problem caused by psychological issues such as fear of commitment, or conscious/unconscious repression of sexuality, as animals are presumed to be incapable of both, although this rests upon the assumption that asexuality has the same cause in humans and animals.

I think this was the article that Shaedofblue might have been trying to find- this is I think the commonly cited Ram study:

http://www.biolreprod.org/content/67/1/263.full

Link to post
Share on other sites

In any gregarious social animal, there is a hierarchy in the group largely centred around sexuality. I would venture to suggest that SOME "subordinate" animals of social species (eg. wolves, lions, meerkats, great apes) are to some degree asexual. They don't particularly contest the alpha animals because they don't particularly care if they get to mate or not.

Followed to its extension, I'd say that I'm arguing that asexuality in social animals serves an important, cohesive function for the group when reproduction amongst all animals is not possible. There is always a need for caretakers and hunters and watchmen, and all of these activities are difficult to engage in if you're constantly trying to get laid or move up the sexual hierarchy.

I'd actually argue against that completely from a behavioral standpoint. With respect to wolves, female wolves don't mate not because they don't care whether they get to, but because the dominant female harasses them so much that they never come into heat. Male wolves again don't mate not because they are asexual and don't want to, but because the dominant male remains very very close to the dominant female throughout her heat cycle and because the dominant female generally would not permit them to mount. The existence of things like the canine post-coital tie, intended to stop other males from copulating with a female in heat, sort of shows this point. If the lower-ranking males were asexual and uninterested, the tie would be selected against very very quickly--it can't be safe for even a large predator to be wandering around tied by its genitals to its mate for a couple of hours!

With respect to lions, I don't know where you're getting the idea of subordinate lions not mating, because all lions currently part of a pride mate. All females of breeding age mate with the dominant male or males when they come into heat regardless of their status within the pride. In the case of a pair or occasionally trio of males holding a pride, there is usually one dominant male who has first access to mating partners, but all males mate with receptive females. As for males not currently holding a pride, well, that's the equivalent of a human who for whatever reason can't attract a mate, not one who isn't interested in the first place.

Meerkats I'm not familiar with, and I'm not as familiar with ape reproduction as I am will wolves and lions, but I do know that in chimpanzees subordinate males copulating with females when dominant males aren't looking is very, very, very common. In general, I would argue that social subordinate animals prevented from mating by dominant members of the group (and these are males in almost all species; canids are an exception) are not asexual but celibate, and involuntarily celibate at that. There are also entire lines of males in these species who reproduce specifically by being sneaky about it and flying under the radar of the dominant animals, actually.

The only social animal species which reproduce sexually I would argue have truly asexual members as a rule and not an uncommon exception are social insects. I think you could make a valid case for worker bees being asexual, for example. Maybe naked mole rats. And of course truly asexually reproducing animals such as amoeba qualify, too, but these are largely unicellular. Would self-fertilizing hermaphroditic species count as being asexual, even if they are technically reproducing via sexual reproduction?

Link to post
Share on other sites
  • 3 years later...

Would self-fertilizing hermaphroditic species count as being asexual, even if they are technically reproducing via sexual reproduction?

Bannana slugs. Not really unless one refused to mate. I don't think asexuality is defined by what gametes you have - eggs, sperm, or both. I tend to see them as hermaphroditic sexual animals as a generalization.

Link to post
Share on other sites
Guest
This topic is now closed to further replies.
×
×
  • Create New...