Evolution - Reality and Misconceptions
Discussion
TwigtheWonderkid said:
4x4Tyke said:
Infertility and modern treatment is an interesting one, so let's consider some of the different scenarios.
- Fertile female with infertile male - Today this is medically solved by a sperm donor, in history it was probably solved by adultery. A selective pressure on genes for women more prepared to cheat. Another truish aphorism is the hunky gardener/gamekeeper seeing to the lady of the house. Cuckolding at work, genetic statistics put this at a few percent in modern Britain. Cheating is natural selection at work.
- Infertile female/fertile male - Solved today with egg donation or surrogacy, in history it was probably solved by cheating or trading up to a younger, more likely fertile woman. Not doing that brings your line to an end, again cheating genes is natural selection at work.
- Both infertile, Today this can be solved with egg & sperm donation, donor or surrogacy with sperm donor, these infertile lines come to an end.
- All above: Adoption, evolutionary fit orphans are more likely to survive; once again natural selection at work. Historically intra-family adoptions was quite the norm. This is a slight selective pressure towards related genes and selects towards our social species status. Families that don't follow this strategy have slightly lower chance of perpetuating their genes.
Fertile Female/infertile male: Likely to be cause by low sperm count or low motility sperm or viscous semen. Easily addressed by IVF or ICSI using the infertile males actual sperm. Hence the issue can be passed to future generations of males.
Infertile Female/ fertile male. Likely to be caused by a blockage issue rather than an egg issue. Damaged fallopian tubes, endometriosis. Easily solved by IVF, using the woman's own eggs, again passing the issue to future generations of females.
Both Infertile: If due to both of the above, again solvable using the actual couples own sperm and eggs, passing the issue on to future generations.
Donor eggs and sperm make up only a small part of infertility treatment.
Using the term 'actual truth' suggests I'm wrong in principle. I'd argue that what you're setting out is a different set of selective pressures, but I think you'd agree that evolution through natural selection is still at work in your scenarios, over time they will probably see less reproductive success.
In the situation for a fertile woman with infertile man, I suggest that using a health sperm donor seems like the best strategy*** for her genes. It is a medical mechanism to the same cheating strategy. Also, I may be wrong, but in the female cases, unless the genetic component of infertility is from the mitochondrial DNA, that female infertility would be slowly deselected by X chromosomes of the males over time.
In the case of male genes resulting in low fertility, you're suggesting they are probably doomed (bar fresh mutations or cross gene interactions). Which is essential what I said, you seem to be reaching the same endpoint by a different route, unless I've misunderstood. I don't see any way around that. Unless it is a biding time strategy until medicine can master genetic fixes.
Good comments, it has made me refine my thinking.
- * As an aside, using the word strategy is this way make me uncomfortable, it implies a degree of anthropomorphism that just isn't there, but I can't really think of a more appropriate word, most of the alternatives are even worse.
4x4Tyke said:
- * As an aside, using the word strategy is this way make me uncomfortable, it implies a degree of anthropomorphism that just isn't there, but I can't really think of a more appropriate word, most of the alternatives are even worse.
TwigtheWonderkid said:
How many people who don't need fertility treatment to reproduce wouldn't be reproducing anyway, if "hardcore evolution" is the benchmark.
Anyone who gets glasses in childhood or teens, they wouldn't survive in the wild. Many everyday childhood illnesses would have finished people off without medicine, vaccinations etc. Any broken bone etc.
Most of us probably aren't truly fit to reproduce.
I would argue that humans are evolving beyond basic biological evolution. Apart from the tools that allow non-survival traits to survive we are developing the technologies to fix genetic faults and even improve on nature, depending on your definitions of fix and improve of course. For some of us at least our intelligence allows us to change our behaviour from that purely dictated by our genetic imperatives.Anyone who gets glasses in childhood or teens, they wouldn't survive in the wild. Many everyday childhood illnesses would have finished people off without medicine, vaccinations etc. Any broken bone etc.
Most of us probably aren't truly fit to reproduce.
Of course we are also affecting the rest of nature to various extents, whether by direct breeding or genetic changes or just environmental pressure.
An interesting argument/discussion would be how development of intelligence serves our genes and if intelligence will cause us to be too successful before it allows us to survive long term.
TwigtheWonderkid said:
What you quote above are the less common solutions. The actual truth is:
Fertile Female/infertile male: Likely to be cause by low sperm count or low motility sperm or viscous semen. Easily addressed by IVF or ICSI using the infertile males actual sperm. Hence the issue can be passed to future generations of males.
Infertile Female/ fertile male. Likely to be caused by a blockage issue rather than an egg issue. Damaged fallopian tubes, endometriosis. Easily solved by IVF, using the woman's own eggs, again passing the issue to future generations of females.
Both Infertile: If due to both of the above, again solvable using the actual couples own sperm and eggs, passing the issue on to future generations.
Donor eggs and sperm make up only a small part of infertility treatment.
Sadly it doesn't always work, I have the issue (emboldened) and after 4 rounds of IVF still no result for us. I think for some the problem is so large that using ones own sperm is just not an option, it appears my swimmers just no interest. But yes, for evolution purposes, by using science to overcome nature we ensure that some problems may continue down the line. Although I don't know if there's evidence of infertility being passed to the next generation. I guess for infertility it's just one of those things that happen sometimes, though for me in particular I think my problem can be traced to a specific event (receiving a very severe kick to the plums at 14 years old), however I know people who have suffered a similar trauma but can still have children.Fertile Female/infertile male: Likely to be cause by low sperm count or low motility sperm or viscous semen. Easily addressed by IVF or ICSI using the infertile males actual sperm. Hence the issue can be passed to future generations of males.
Infertile Female/ fertile male. Likely to be caused by a blockage issue rather than an egg issue. Damaged fallopian tubes, endometriosis. Easily solved by IVF, using the woman's own eggs, again passing the issue to future generations of females.
Both Infertile: If due to both of the above, again solvable using the actual couples own sperm and eggs, passing the issue on to future generations.
Donor eggs and sperm make up only a small part of infertility treatment.
AshVX220 said:
TwigtheWonderkid said:
What you quote above are the less common solutions. The actual truth is:
Fertile Female/infertile male: Likely to be cause by low sperm count or low motility sperm or viscous semen. Easily addressed by IVF or ICSI using the infertile males actual sperm. Hence the issue can be passed to future generations of males.
Infertile Female/ fertile male. Likely to be caused by a blockage issue rather than an egg issue. Damaged fallopian tubes, endometriosis. Easily solved by IVF, using the woman's own eggs, again passing the issue to future generations of females.
Both Infertile: If due to both of the above, again solvable using the actual couples own sperm and eggs, passing the issue on to future generations.
Donor eggs and sperm make up only a small part of infertility treatment.
Sadly it doesn't always work, I have the issue (emboldened) and after 4 rounds of IVF still no result for us. I think for some the problem is so large that using ones own sperm is just not an option, it appears my swimmers just no interest. But yes, for evolution purposes, by using science to overcome nature we ensure that some problems may continue down the line. Although I don't know if there's evidence of infertility being passed to the next generation. I guess for infertility it's just one of those things that happen sometimes, though for me in particular I think my problem can be traced to a specific event (receiving a very severe kick to the plums at 14 years old), however I know people who have suffered a similar trauma but can still have children.Fertile Female/infertile male: Likely to be cause by low sperm count or low motility sperm or viscous semen. Easily addressed by IVF or ICSI using the infertile males actual sperm. Hence the issue can be passed to future generations of males.
Infertile Female/ fertile male. Likely to be caused by a blockage issue rather than an egg issue. Damaged fallopian tubes, endometriosis. Easily solved by IVF, using the woman's own eggs, again passing the issue to future generations of females.
Both Infertile: If due to both of the above, again solvable using the actual couples own sperm and eggs, passing the issue on to future generations.
Donor eggs and sperm make up only a small part of infertility treatment.
And yes, any condition that's due to environmental issues of course cannot be passed on.
It reminds me of a conversation I had with a senior person in my industry. Very highly qualified, very clever. We were talking about someone we both new who was due to have his first child. and this very clever guy said "I hope his child is healthy, and has both his legs." (Dad had lost a leg in a motorcycle accident). We then had a 10 minute argument about whether or not this could be passed on, and this guy was convinced it could be. It was only when I hit him with the question as to why kids aren't born with tattoos or pierced ears or circumcised, inherited from their parents, that the penny dropped. And believe me, this is not a stupid man.
Just goes to show how uneducated people are about the whole topic.
TwigtheWonderkid said:
Sorry, you're right. "Easily solved" was a ridiculously flippant. It's not easy and it's often not solvable.
And yes, any condition that's due to environmental issues of course cannot be passed on.
It reminds me of a conversation I had with a senior person in my industry. Very highly qualified, very clever. We were talking about someone we both new who was due to have his first child. and this very clever guy said "I hope his child is healthy, and has both his legs." (Dad had lost a leg in a motorcycle accident). We then had a 10 minute argument about whether or not this could be passed on, and this guy was convinced it could be. It was only when I hit him with the question as to why kids aren't born with tattoos or pierced ears or circumcised, inherited from their parents, that the penny dropped. And believe me, this is not a stupid man.
Just goes to show how uneducated people are about the whole topic.
No Problem, I wasn't having a dig, just saying it's not always easy to resolve, I guess depends just how lazy and how few swimmers we have.And yes, any condition that's due to environmental issues of course cannot be passed on.
It reminds me of a conversation I had with a senior person in my industry. Very highly qualified, very clever. We were talking about someone we both new who was due to have his first child. and this very clever guy said "I hope his child is healthy, and has both his legs." (Dad had lost a leg in a motorcycle accident). We then had a 10 minute argument about whether or not this could be passed on, and this guy was convinced it could be. It was only when I hit him with the question as to why kids aren't born with tattoos or pierced ears or circumcised, inherited from their parents, that the penny dropped. And believe me, this is not a stupid man.
Just goes to show how uneducated people are about the whole topic.
I actually remember now that I think about it, the consultant we saw did actually say that the issue wouldn't be passed to the next generation, maybe because it was caused by trauma. If it was a genuine genetic thing, then maybe it would have been.
That's crazy about the guy, thinking that the loss of a leg due to an accident could be passed down, but come to think of it I know a lot of very intelligent people that believe all sorts of weird crap, one particular guy that thinks even current rocket launches are fake! LOL
TwigtheWonderkid said:
I think the current must read book for the latest on evolution is The Greatest Show On Earth by Richard Dawkins. And for those who dislike Dawkins, it's written in his capacity as one of the world's leading evolutionary biologists as opposed to one of the world's leading atheists.
It's a really great book.
Jerry Coyne - Why Evolution is True is a good read, and quite "dry"....It's a really great book.
also, Adam Rutherford - a Brief History of Everyone Who Ever Lived is a very interesting, and funny read.
The topic of epigenetics has arisen in another thread, lacking some good examples of the top of my head I've search out some details and this is quite a good article explaining what it's all about.
In simple terms, epigenetics is the study of how the environment can influence gene expression. Were genes alone do not provide a full answer. One example is Schizophrenia, it is know this has a strong genetic basis, but twin studies show that if one twin suffer from it, there is only a 50% chance the other will get it. If it was entirely genetic it would be a 100%, so what is going on.
http://www.naturalhistorymag.com/features/142195/b...
I'm not convinced by the standard explanation of evolution being a slow gradual process. I find it much easier to accept the theory of punctuated equilibrium and the suggestion that animals can express genes when environmental conditions to demand it, some of which may alter dna. A kind of will full evolution.
That said I've been willing myself to grow a bigger cock for years and no luck.
That said I've been willing myself to grow a bigger cock for years and no luck.
FredClogs said:
I'm not convinced by the standard explanation of evolution being a slow gradual process. I find it much easier to accept the theory of punctuated equilibrium and the suggestion that animals can express genes when environmental conditions to demand it, some of which may alter dna. A kind of will full evolution.
That's not making a great deal of sense to me. Can you explain what you mean in terms of molecular biology? otolith said:
FredClogs said:
I'm not convinced by the standard explanation of evolution being a slow gradual process. I find it much easier to accept the theory of punctuated equilibrium and the suggestion that animals can express genes when environmental conditions to demand it, some of which may alter dna. A kind of will full evolution.
That's not making a great deal of sense to me. Can you explain what you mean in terms of molecular biology? I don't know of the biology, I'm just a layman, but Ive read a few things like this and believe Dna is not set in stone and animals have the ability to alter their Dna or at least express hidden features and unlock new levels. See the fish who change sex etc..
a quick youtube of some of Dawkins' interview helps to explain a few things - the development of eye for example is a good topic around evolution and the Blind Watchmaker is another good read.
Part of my confusion with evolution is how many types of the same species exist and continue to "evolve" within their species group but don't fundamentally change.
taking human intervention and breeding out of the equation take a wild animal, a lion for example. they have evolved into apex predators over millions of years but are they still evolving ? yes maybe through survival of the fittest getting faster or stronger but they are not developing into say a Tiger...why are there lions and tigers and not just one species?
that stuff kind of messes with my head a bit. clearly spiders wouldn't eventually evolve into "lions" but it feels like they are sort of happy where they are...
Part of my confusion with evolution is how many types of the same species exist and continue to "evolve" within their species group but don't fundamentally change.
taking human intervention and breeding out of the equation take a wild animal, a lion for example. they have evolved into apex predators over millions of years but are they still evolving ? yes maybe through survival of the fittest getting faster or stronger but they are not developing into say a Tiger...why are there lions and tigers and not just one species?
that stuff kind of messes with my head a bit. clearly spiders wouldn't eventually evolve into "lions" but it feels like they are sort of happy where they are...
Nom de ploom said:
taking human intervention and breeding out of the equation take a wild animal, a lion for example. they have evolved into apex predators over millions of years but are they still evolving ? yes maybe through survival of the fittest getting faster or stronger but they are not developing into say a Tiger...why are there lions and tigers and not just one species?
Stripes are better camouflage in the jungle, plain light brown better on a plain. Obviously a bit more to it than that.ash73 said:
Nom de ploom said:
Part of my confusion with evolution is how many types of the same species exist and continue to "evolve" within their species group but don't fundamentally change.
Indeed, confusing aspect to me is all the basic building blocks (eyes, ears, noses, mouths, spines, limbs, tails, wings, etc) seem to have evolved incredibly quickly during the Cambrian explosion, since then it's just be a case of switching things on and off and amplifying features that are useful. Why no new features?But sure, extra features would be great if they're codes in our Dna already I'd love to have the x-men upgrade.
Edit to add the "peppered moth" is as close to a good example we have of "evolution" in action but there is a myriad of exams of animals which can change colour at will so its not massively impressive. Speciation, I believe, in a complex organism has never been observed which is indeed why there is so much wonder at whether it actually happens or not.
Edited by FredClogs on Thursday 30th August 13:39
ash73 said:
Indeed, confusing aspect to me is all the basic building blocks (eyes, ears, noses, mouths, spines, limbs, tails, wings, etc) seem to have evolved incredibly quickly during the Cambrian explosion, since then it's just be a case of switching things on and off and amplifying features that are useful. Why no new features?
Once you have features meaning you can move, touch, eat, detect light, heat, sound and smells - what 'new feature' would convey a significant survival advantage compared to tweaking or optimising those existing features?FredClogs said:
otolith said:
FredClogs said:
I'm not convinced by the standard explanation of evolution being a slow gradual process. I find it much easier to accept the theory of punctuated equilibrium and the suggestion that animals can express genes when environmental conditions to demand it, some of which may alter dna. A kind of will full evolution.
That's not making a great deal of sense to me. Can you explain what you mean in terms of molecular biology? I don't know of the biology, I'm just a layman, but Ive read a few things like this and believe Dna is not set in stone and animals have the ability to alter their Dna or at least express hidden features and unlock new levels. See the fish who change sex etc..
otolith said:
OK, but that is altering the expression of a gene during an individual's life. It isn't altering their genome. They will still pass the same sequence they were born with to their offspring.
This kind of thing?https://www.newscientist.com/article/2127103-squid...
Toltec said:
otolith said:
OK, but that is altering the expression of a gene during an individual's life. It isn't altering their genome. They will still pass the same sequence they were born with to their offspring.
This kind of thing?https://www.newscientist.com/article/2127103-squid...
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