Jump to content

jp255

Senior Members
  • Content Count

    195
  • Joined

  • Last visited

Community Reputation

25 Nice

About jp255

  • Rank
    Baryon
  • Birthday 04/26/1991

Profile Information

  • Location
    UK
  • Interests
    Playing the piano, Reading, Racquet sports, tv, films, video games
  • Favorite Area of Science
    Genetics
  1. That is incorrect. Before I go into why, I think it is helpful to use the fitness landscape (https://en.wikipedia.org/wiki/Fitness_landscape) to visualise the process of evolution and it's progression over time. The landscape depicts the phenotype possibilities of a trait (e.g wing) that evolution can find by mutation. The fitness landscape varies in any given environment and changes if environment does, it is depicted by peaks (high fitness) and troughs (low fitness). Natural selection usually drives evolution upwards over time towards a peak (but not necessarily the highest peak in the landscape). The statement is incorrect because evolution is capable of restricting the possibilities of the fitness landscape that can be found. I'll first start by highlighting that there are two senses of randomness that can affect the progression of evolution. The randomness of the number of mutations that occur and the randomness of the outcome of each mutation. I believe that for the most part this thread has focused on the outcome. Number of mutations: Mutation rate is not random, is subject to selection and is non-uniform amongst organisms. Some examples (approximations, google them yourself for more accurate values) of average mutation rate include HIV-1 (1x10-3 mutations per base), Influenza (4x10-4 mpb), Humans (1x10-8 mpb). The fidelity of replication enzymes is subject to selection and this usually accounts for the differences between various organisms. This trait contributes significantly to the process of evolution itself, for the mutation rate affects the speed at which evolution attempts to move on the fitness landscape. To give a tiny bit of perspective on the importance, mpb of 0 results in no movement on the fitness landscape (can’t evolve by definition, but environment could change to favourite current phenotype) and mpb of 1 results in random teleporting around the fitness landscape (too much risk of a generation going extinct due to a string of bad outcomes of mutations, can’t survive millions/billions of generations with this strategy). To bring it back to the analogy used previously (blind evolution walking around the fitness landscape), the rate at which it moves is not random and the rate itself varies between organisms. This means that evolution does influence it's own movements, and I think that does qualify as planning (just not a plan to go to a specific place on the fitness landscape). Outcome: This area is fairly difficult to test given the number of test sites in the human genome of 3.3 billion and the low mutation rate per site. I believe the position is that there is no evidence that certain outcomes of mutation are more likely for standard base mutations (transitions and transversions) because of natural selection. However, studies of human, dog and mouse crossing over (homologous recombination in meiosis) has conclusive evidence of non-random rates of occurrence and non-random outcomes as it’s been shown that in the human genome there are hotspots/specific sequences at which crossing over occurs (The protein regulating this directly manipulates the outcome of crossing over so the former belief of random no longer holds). The reality therefore seems to be random selection from a set of non-random sites (overall largely non-random in the outcome sense given the range of possibilities is significantly reduced. This is an important discovery, the implications to the process of evolution are complex but there is strong evidence that the gene coding for the protein that performs this function is evolving rapidly in the human genome suggesting an advantage. This is a trait discovered in the fitness landscape that directly impacts the process of evolution itself since outcome possibilities are distorted. http://www.nature.com/ncomms/2014/140708/ncomms5370/full/ncomms5370.html Back to the analogy: Human evolution is an example of evolution restricting the possibilities in the fitness landscape that it can find, but it is difficult to say what the landscape looks like. I guess some areas are fenced off. Again I think this is enough to qualify as planning, and self-directing (just not to a clear-cut path extent). Overall, exactly how evolution moves on the landscape is quite complex, and the understanding is limited. The process of evolution is non-uniform amongst organisms and is not static (mutation rate selection and crossing over mechanisms evolved and changed over time).
  2. I agree that the word can be easily misinterpreted, but the word causative is reasonable if one specifies what the cause refers to (the occurrence/incidence (e.g. throw a baseball) or the outcome variance (e.g curvreball, under arm throw, over arm etc.). The term "causative contributor" and predisposition overlap somewhat, perhaps entirely. If a predisposition (occurence or outcome variance) has a known genetic basis, then it is reasonable to say that genetics contributed to the cause of the particular outcome the predisposition relates to. Coming back to homophobia now. On the basis of the evidence posted here it is reasonable to suggest that some individuals may have a genetic predisposition to hold a negative attitude towards homosexuals (homophobia). It is also reasonable to say that genetics is a causative contributor of a negative attitude (considered as a possible outcome!) toward homosexuals.
  3. jp255

    The X cromossome

    To the OP, read my post there. I don't know much about Turner's syndrome or the physiology of it, but there are some clinically relevant genetic explanations. http://www.scienceforums.net/topic/70254-genetics/?hl=turner#entry711647 The points can be extended to klinefelters also. Though I don't know if 2 chromosomes in klinefelters will be inactivated by the inactivation system. How is this relevant to the OP's question? and what are you even talking about? Perhaps you can elaborate on this?
  4. Sarcasm? I already touched upon the useful point I felt he was raising. I didn't understand many of the points he raised, and I did agree with you about the false dichotomy he depicted. To be honest I succumbed to a lot of TLDR behaviour, I apoloise for that. I agree with you that religion is essentially hijacking the "good" already within us and claims that this good is rooted in religion. This point doesn't mean that the religious teachings, bible or whatever, do not contribute to the cause of good behaviours. As for the promotion of bad, you raised the examples of religion condoning various bad behaviours and I agree also that religious teachings/bible do promote bad. The promotion of bad in this way might contribute to the cause of bad behaviours. I don't know how effective words on a page are at causing someone to act violently, were they inherently violent before reading it? did the words really contribute to the cause of the event? I would rather have evidence before deciding what opinion to have on religion causing good or bad. To be honest though, I think the "religion causing bad" arguments are totally unneccessary. The fact of the matter is the religious texts promote bad, and there is no good reason to leave them in there. That is a valid criticism as far as society is concerned, as the promoted behaviours are against the law. There is a simple solution though, get rid of bad morals, and leave only the good morals.
  5. I was considering posting some of the arguments in the biology forum, but I think the discussion would become speculative rapidly. This topic concerns how we (society) determine whether or not an individual is responsible for an action, and for the sake of this topic the definition of responsibility is "being accountable for something within one's own power, control or management" (dictionary.com). I argue that the way in which we determine/quantify "one's own power/control" is inaccurate, and that most probably hold a mistaken view of responsibility (by thinking of it as simple discrete categories, e.g. not responsible, responsible). Before I argue this I need to present arguments which attempt to properly describe the causative contributors of an action as being under one's own control. I'll try present the argument as clearly as I can, in a premise1 + premise 2 ... leads to the conclusion format. Conclusion1: Genetics and environmental factors are causative contributors of actions. Premise 1: Genetics, additive genetics, epistasis and gene-environment interactions can account for and explain individual differences of behavioural and personality traits in human populations. The scientific literature which suggests this is substantial, with MZDZ twin studies determining that genetics substantially contributes to human bahaviours. http://www.ncbi.nlm....pubmed/21761238 is an example, there are many many studies of this kind which examine genetic contributions to other human behaviours. There have been a few threads in the biology forum recently that have other links in too. Premise 2: The study populations are representative of human populations, and allow for the extension of premise 1 to human populations in general. Genetics and some aspects of environment now need to be argued to be out of an individuals control. Conclusion2: Genetic and, to some extent, environmental factors, are out of an individuals control. Premise 1: An individuals genetic make-up is currently fixed throughout one's life (somatic mutations are irrelevant for this discussion). The environment and most environmental factors one is exposed to as one grows up can't, for the most part, be reasonably rejected. Premise 2: An individual who desires an alternative genetic make-up cannot get one, and an individual only has a certain amount of control over the environmental factors that he/she is exposed to. In light of the arguments and conclusions above: Final Conclusion: Responsibility should be considered as a scale or spectrum (as opposed to simple discrete categories, e.g. not responsible, responsible) as the the level of one's own control, concerning specific generalised behaviour (e.g. petty crime), can vary substantially between individuals. Premise 1: Conclusion 1 is correct Premise 2: Conclusion 2 is correct The way in which I suggest responsibility should be considered, is with respect to how much control the individual has. More specifically, the uncontrollable elements can most easily be considered to determine the responsibility, because at the moment factors which can be considered as allowing for control are elusive, and evade identification. So I suggest a scale concerning the combined value of uncontrollable factors, 0 means individual has no uncontrollable factors and so he/she is responsible, 100 is opposite. I think it is reasonable to make this conclusion based on the evidence that we currently have. The evidence (and therefore premises) can be criticised, though the conclusions are reasonable imo. Of course further research is needed in order to obtain more direct evidence. I could go on but I think this post is long enough now, even with omission of proper explanations, but the implications of the conclusion are interesting though, for ethics, law and determinism/indeterminism. Thoughts?
  6. I actually think Sam's criticism on some points was useful, the conversation just wasn't particularly useful though. With regards to religion causing good and bad. Where is the evidence for or against? and how valuable is the evidence (suggestive?, proof?)? can it explain how much religion contributes to the cause of both "good" and "bad" behaviour? Are your conclusions reasonable? and are you being unbiased here? I would take a guess that religion is a factor which can influence behaviour, though in reality there are many other factors which can contribute to an individual's behaviour. This is apparent from various heritability and GWAS studies. The point of Sambridges posts was to stress that one should take care when claiming religion is a direct causative agent of an event. Imo, someone stating they acting in the name of religion is NOT evidence that religion caused the event occur. Regarding the delusional thing. It has already been stated that there are many sects of religions. They can't all be the sole truth, so we can calculate the probability that each variation is correct, and that probability can then become the probability that the description delusional is wrong. Given that the probability the description, delusional, has a low chance of being wrong, it is a reasonable description.
  7. Yes, that is correct. The data gives no insight into functional role. The data suggests that genetics accounts for a certain percentage of the observed variance in sexual attitues toward homosexuals. So one can say that genetics contributes to the causation of the observed behaviours, rather than saying genetics simply allows for the possibility of homophobic attitudes. That is a possibility that can't be refuted, yes. I disagree here. The correlations actually do suggest that genetics are a causative contributor of the observed attitudes toward homosexuals. Monozygotic twins were observed to be concordant significantly more frequently than dizygotic twins. Perhaps you can elaborate and explain why the evidence should not be considered to be suggestive evidence of genetics being a causative contributor? OK. I am a bit confused. You think genetic predisposition is a possibility, but don't think the correlations adequately suggest genetics as a causative contributor? Whilst we can't accurately predict what kind of response a random individual will have, maybe with perfect knowledge of genetics and environmental factors we could.
  8. http://www.ncbi.nlm.nih.gov/pubmed/21761238 This study reports heritability for violent crimes (convicted offenses I believe) in a Swedih population, and the authors note the results are similar to those obtained from a twin study using self-reported antisocial behaviour. It seems likely that genetics does contribute to the variance observed in antisocial behaviour. I guess it is fair to assume that genetics probably contributes to individual differences that concern douchebaggery related behaviour.
  9. It's also very important to consider sexual selection. OP seems to have not considered the possibility of sexual selection. My overall opinion is that there are many possible explanations, and that many of those explanations are as unsupported as each other. You can't see how violence can potentially be a successful strategy? like rape? how does evolution become unconcerned with a trait then? Evolution is not concerned with anything. Genetic drift (the randomness you were talking of) is an important contributor to the progression of allele frequency change and evolution on the whole, so neutral traits shouldn't be neglected. Also, the term neutral is somewhat confusing as a neutral trait today might be an individuals saving grace tomorrow (environment change). I don't know if evolutionary biologists consider behaviours to be traits or not. I would imagine it is a matter of definition. Though I myself consider them to be traits, or at least as a phenotype. Imo, behaviours can still be described in the same way any other traits can and it is useful to consider them as traits. You seem to have answered your own question? My educated guess would describe the behaviour you detailed as a neutral trait. Would you describe the act of having sex as not a trait michel?
  10. I think the observed higher prevalence of homophobia in heterosexuals is not doubtful, I believe there were other supportive references along with the same observation in the study population. I do agree that the blunt categories "homo, hetero and bi" are not ideal, but I think one can still draw a rather loose conclusion nonetheless. The criticism of the terms "homo, hetero and bi" should only go so far imo, sure they are blunt tools and do not allow for fine-tuned descriptions, but they still a useful measure when considered as self reported sexual identity. In this respect, the terms are useful since they are used very frequently in social settings. With respect to the correlation of sexual arousal to homophobia vs the study I presented. Have you considered that the conclusions drawn from both studies are compatible with each other? it seems you are comparing apples and oranges, the population described as sexually aroused by same-sex activity vs "hetero, bi and homo" populations require their comparability to be investigated via experimentation. If you are to deem the conclusions doubtful, then you need to provide adequate reasoning and support. To Monday: inverted homophobia? what's that. Arousal tendencies and internal conflicts are other areas to explore, though those aroused by same-sex won't necessarily have or seek out same sex themselves. I'll rephrase your sentence to "It is nothing special that genetics allows for personality". The authors didn't mean that. Genetics allows for all traits and phenotype, but how much can it explain about the variance of the trait or phenotype? It is an important difference. I am actually a little surprised that 30-50% genetics can explain the populations variance of personality, but I think it is quite difficult to anticipate the contribution amount with a reasonable level of certainty. I haven't searched for it. It ain't hard to search, try google scholar, or go into pubmed and search in there (try both PMC and pubmed databases, maybe others too). I am somewhat less interested in arousal, as arousal doesn't necessarily mean an individual will actually engage in same-sex behaviour.
  11. T "It is genetic" is a bad phrase. "Genetics contributes" is a better one. Explaining selection is a difficult feat. Detection of selection can be challenging also, and it usually requires DNA sequences (in this case we don't know what the contributing genes are, so no DNA to work with). It will be a while before we can provide reasonable explanations for selection that is backed with adequate evidence.
  12. I would like to see the adoption of such laws, and I would support a court case in which an individual seeks to sue his/her parents for the suboptimal lifestyle they caused. I don't expect tlaws such as these to be implemented any time soon, and maybe my prediction won't even come true. Ultimately, this is just my opinion on this subject area, and I believe it is more reasonable than the current laws. Much of your post was rubbish because it lacked explanation. My point was that the age of genetic counselling is irrelevant, and so is the 100,000 years of which you speak. Genetic counselling is around today and is used quite frequently. Awareness of genetics is also now at a level to make decision with regards to the laws surrounding this issue, it is irrelevant if it wasn't 200 years ago. You say you are to actively oppose me. Why? is it because you don't think it is worth enacting the laws I propose? or do you disagree with my reasoning? What is the point of this? Such an argument could equally be applied to any and every action. Perhaps you can elaborate further on your claim that my proposal would result in worldwide suffering.
  13. You do raise a good point. Science can progress to find a cure in the future, but that doesn't help us now. We have a dilemma now, because we have the ability to reduce the risk of transmission yet it is still considered acceptable to subject future children to these risks. Imo, even if the laws I propose go obsolete it is better to brdge the gap and prevent harm rather than do nothing and leave people to consider these risks as acceptable. It just doesn't make sense to ignore the techology we have today, the law I propose would promote its use somewhat. You say "recently", but genetic counselling has been around for many years.
  14. It only occured to me just yesterday to actually look on pubmed for some scientific literature on this topic, seems I was infected by the bad reasoning e-virus present in this thread. I think it is important to point out that exposure to (or awareness of) homophobia and what causes one to adopt a homophobic mentality should be considered separately. I can't stress this enough, and I think people in this thread may have been arguing (without saying) for either or, or perhaps both. I think this can lead to confusion, especially when considering the homophobic baby line of reasoning (which btw, is not evidence that homophobia isn't genetic). I found some literature which provides suggestive evidence that attempts to explain both the contribution of genetics and evironment to the variance of the trait homophobia in a population. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2292426/ They basically just looked at MZ DZ correlations to calculate Heritability, and the more specific components (ACDE). The takehome is that there is substantial contribution from both genetics and environment, and it is not heavily one or the other as people have suggested here. Also, it is very important to remember that things are not so simple as they appear and can't always be simply categorised as being "learned/taught" or the opposite. These results suggest that the factors which cause anyone individual in a population (assuming population from study is representative) to adopt a homophobic mentality can be of genetic and environmental nature, and that both genetics and environmental factors play important roles (if you want values go to the paper). This evidence trumps pretty much all reasoning used in this thread, it can be critiqued however. Other interesting observations (mentioned in the paper): 1) homophobia prevalence is higher in males than in females 2) homophobia prevalence is higher in heterosexuals than homosexuals 3) the term "Homosexuality" will be interpreted by most as a reference to gay males and not to females 4) Heterosexuals have different attitudes towards gay males and females, with gay females being viewed in a less negative light.
  15. So does it also disturb you that very unpleasant diseases like Huntington's disease still exist today? HD prevalence could almost be reduced to de Novo mutations only, if people placed more value in their child's wellbeing. I wonder if the families segregating those traits feel guilt for deciding to initiate the high risk biological coin flip that determines their childs wellbeing. Whilst I myself agree with the adoption of laws on this topic that would deny certain people the choice to procreate, I have suggested the adoption of laws that wouldn't. I do think it is reasonable (and I think even society should agree) to describe the couple in my scenario as negligent, and I think it is reasonable to seek justice for that negligence. The justice could at the very least be paying for all of the medical bills (from birth the death) associated with the condition the couple have inflicted upon their child. That would at least offer the child some form of compensation for the entirety of his/her life. Depends what you are calling Nazi-ish. If you think my intervention is Nazi-ish, then surely you should think it is Nazi-ish to punish the negligent texting driver? Why shouldn't the acceptable level of genetic disease risk be brought down to what is possible nowadays? Why not make more use of the scientific technology and knowledge we have today? Seems like we are still living in the past, back when one couldn't easily manipulate inheritance patterns. Maybe it is simply to early to be suggesting such intervention, these things take time? Maybe it took a while for phone usage whilst driving to be forbidden? I believe it is too early for there to be court cases of this kind. However, I predict there will be some in the future (when the children of today are adults).
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.