Australia to vote on Gay marrige - Page 37

On October 22 2011 12:40 meatbox wrote:

Fun fact; blue eyes was the result of genetic inbreeding which occurred around 5000BC, lol.

Homosexuality doesn't occur naturally amongst animals, a dominant male 'rapes' competing males in an effort to humiliate and stamp their authority, happens in the navy quite often, homosexuality is the result of a feminine mind placed in a masculine body.

On July 14 2011 12:28 Masamune wrote:
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Yes, I’d hate genetics as well if I couldn’t grasp it...

First of all, his quote doesn’t suggest him being a medic/doctor at all; it was just an excuse for you to state that you were in medical school, as if stamping a seal of authority on your post...which is actually quite embarrassing because if my doctor pretended to be so informed on a subject like genetics and evolution (so integral to the field of biology) when he really had no inkling on the subject, I’d probably find myself second guessing his medical advise as well. Then again, many doctors are clueless about these fields because it’s not essential to the practice of medicine (even though medicine is heavily based upon it) so I guess another one bites the dust.

Anyway, let’s break down your post and point out the many flaws in it.

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Actually, it’s still somewhat debateable as to why many organisms switched from asexuality to sexuality, factoring in all the costs associated with the latter, but the strongest theory as to why it occurred was definitely not to encourage reproduction; it was most likely to increase genetic variation in a dynamic and changing environment (which many multicellular organisms occur in), allowing evolution to work faster on these sexual organisms.

Furthermore, if you think about it for a second, you would realize that sexuality would go against preserving one’s own genome as it causes you to pass on only half of it to your progeny...


You may use the “in general” part of this quote as a cop-out for your misunderstanding, but given the nature of your post, I’d imagine you wouldn’t know how so.

An organism being incapable of reproduction in no way means that their genes have reached a “dead end”. The answer lies in Hamilton’s Inclusive Fitness Theory (which Darwinian evolution is a subset of). To put it in layman terms, if I happened to die in a freak accident today, all my genes could theoretically still be passed on to the next generation due to having biological siblings who share DNA (and therefore genes) with me. This concept is the basis of eusociality in insects, common among many species of the order Hymenoptera.

For those who are scratching their head at this last sentence, many of you have probably seen a wasp hive before of which it is inhabited by usually one queen and workers/soldiers. Well, it so happens that the workers in a colony are generally sterile (extreme but common), forgoing their own reproduction in favour of the gyne who in most cases is their mother. Like homosexuality, this behaviour remained elusive for many biologists prior to Hamilton’s ground breaking work (including Darwin, who considered eusociality as being fatal to his theory of evolution by natural selection) because why would an organism give up its own reproductive success in favour of its sibling? To make this short, many eusocial species (though not all) are generally haplodiploid, so sister workers are more related to each other than they would be to their own son or daughter (0.75 vs. 0.5), thus making sense why they would help take care of their supersisters in favour of their own offspring (the genetics behind this would take another two paragraphs to read so if you’re interested pm me, but I’m losing readers at this point so just take my word for it). Thus, like kin selection can be attributed to eusocial species, it can also be used to explain homosexuality in humans (I’ll get to that later).


I’m not sure if you realize this but CF is a mendelian inherited trait while homosexuality most likely is a quantitative trait so of course the former would be much easier to detect and understand.

Furthermore, if the genetic basis of homosexuality is murky, so is that of intelligence as both are complex inherited traits that have not had a gene identified for either. The theory behind their existence is there but the technology (lack of resolution in detecting biological factors associated with aforementioned traits) is still lagging behind. But we don’t question the idea that smarter parents will tend to have smarter children, despite the lack of proof for the existence of a gene for intelligence so why the fuss with homosexuality? Both traits and twin studies already prove the underling biological component in both (if requested I’ll search them up and post the abstracts here) so perhaps people should revise their perspective on the situation.

And I have no idea why you would even mention allele expression when right before that you mention homosexuality being linked to a “vastly reduced chance of reproduction”. If you were right and there were no continuity in a gay gene’s lineage, why even mention allele expression to begin with? Do you even know what allele expression entails?


Recent studies generally suggest a prevalence rate of between 2-5% in modern Western populations, but as you have conceded, there are many factors that can confound an accurate statistic. For every gay that is open and out, how many are closeted? In some countries you can receive the death penalty for being gay and Western society—although a lot more tolerant nowadays—still has a far way to go before gays even have a neutral portrayal. With that in mind, these recent estimates can at best tell you only a conservative estimate of the prevalence of homosexuality in humans, which cannot be explained by spontaneous mutation rates, but must persist due to biological factors conferring some kind of potential fitness benefit.


Having more adults per children leads to greater survivorship of the latter and if these children harbour a gay gene that is not “active”, can further lead to a larger propagation of the gene. Remember (not sure if it’s even in your memory to begin with...) but the unit of selection is the gene, not the individual or the group.



Once again, you demonstrate your complete lack of understanding of evolution and genetics with this excerpt. Although one’s direct fitness would be greatly reduced due to homosexuality, the same fate would not necessarily apply to their indirect fitness, and the scientific literature supports this perspective.

Your example of Huntington’s disease and its effect of an increased libido/fecundity in females actually parallels what is thought to occur with homosexuality—and this is an advantage from the perspective of the gene for these traits. You need to realize that that’s all that really matters when it comes to evolution. A gene doesn’t care about its bearer but about itself only. If it can increase its propagation at the expense of other genes, then such a scenario is likely to occur.

In either case, evolution can explain these examples that you list. With Huntington’s disease, if I’m not mistaken, the age of onset is generally in adulthood and is a recessive disorder. Thus, people still tend to have kids without knowing they could be carriers of the disease. Furthermore, recessive mutations are hard to weed out of populations because they can hide in heterozygotes, and if it confers an increase in libido/fecundity, could also be classified as a balanced polymorphism (provided that the effect is still present in heteros).

With Cystic Fibrosis, it may be detrimental to be homozygous for the disorder-causing alleles but if you are heterozygous for them, then you can generally live a normal life and also be generally immune from cholera and other diarrheal illnesses. Thus, balanced polymorphism can also explain this disorder's prevalence in the population.

With regards to homosexuality, I found this post in my history (didn’t even realize it was within this same thread as well...I know there are more in other threads scattered on the forum but I guess this proves you didn’t at least read through this one) which explains the evolutionary reason behind homosexuality:





I’m sure (I hope) that you’ve heard the phrase that sociology is a subset of psychology which is a subset of biology which is a subset of chemistry which is a subset of physics which is a subset of math. Well it’s true; evolution is integral to the field of biology and happens to be highly influential in the fields of psychology and sociology, which genetics also plays a major role in. Although the environment does complicate such a complicated issue as homosexuality in humans, it is less influential on many of the other myriad of species in nature used to discern many of its mysteries. Regardless, when you look at homosexuality from an evolutionary/genetic standpoint, you also happen to be looking at it from a psychology/sociological standpoint as well.

Sorry to come off as a douchebag with this monstrous post, but when someone comes into a thread dedicated to a minority group—still persecuted and viewed negatively today—only to try and flaunt their knowledge (or in this case, lack thereof) at the expense of these individuals (because let’s face it, your post was basically implying that homosexuality is a disease almost on par with life threatening ones such as Huntington’s and CF) who already have enough shit on their plates, I had no choice but to reply.