This is an unresolved problem in biology. In general, evolution never makes sense. There is no inherent goal or optimization. If the individual is fit and adapted, it produces offspring. If not, it does not hand down its genes. There is no deeper process involved.
I mean, you could say there’s no inherent goal on anything, goals are always subjective/constructed, so from that perspective nothing ever makes sense.
But I think the question was how is it possible that sex differentiation could have contributed to make us fit and adapted even though in the surface it might seem to be more like an obstacle to reproduction (and thus, survival).
My guess is that specialization allows for higher level social structures that can more easily organize to survive. You have extreme cases with the bees, ants, etc. whose individuals can even have different sets of chromosomes and are very specialized for specific roles, making them so successful that you have them all over the planet for far longer than humans, millions and millions of years with hardly any changes.
But on the other hand, it is weird how sexual reproduction was selected for many times and rarely reverts back.
Like there are a lot of different modes of it in nature, species with more than 2 sexes, species that have 2 sex organs etc. but it does seem that somehow it gets selected for over alternatives.
Two parent reproduction leads to better adaptability. Asexual reproduction leads to the offspring being genetic copies of the parents, which is great if the parent fits well to the environment it is in, but any change to that environment could be catastrophic and lead to the species dying out. With two genetic sources, it allows for greater deviation in the species. So if there is a change in the environment, some will die, but there is a higher likelihood of some individuals being able to adapt better and survive in the changing environment.
I feel the question wasn’t so much about the sexual process (fusion of genetic information of two individuals) but about sexual differentiation (separation of this information into two parts) . At least, to me “uni sex” is not the same as “no sex”. These are different things, in biology you can find creatures that reproduce sexually but do not have sexual differentiation.
Yeah that’s one theory and it makes intuitive sense but if you read the link the person I responded to posted that doesn’t fully explain it and doesn’t necessarily have statistical backing.
Yes… the thing is that with asexual reproduction you can reproduce way more and much faster… so even though each individual division might have less variability, you have many more generations of splits and a bigger population that ends up being forced to spread around more to different conditions and eventually leading to mutations faster than they would have otherwise.
Also, the ease of reproduction makes each individual more disposable, and at that point it doesn’t make as much sense to have more mechanisms to protect your genetic material from mutagens, you can just let the mutants die when they are not fit and produce new ones until ultimately you hit the jackpot and achieve a new resistance. This is what makes bacteria so adaptable, with new strains appearing every day.
While it’s not the reason we have 2 sexes, there is an evolutionary reason for 2 partners to make an offspring, which is likely a big contributing factor
While asexual reproduction is easier, the downside is that the child is almost an exact genetic match of the parent. There’s a lot of reasons why this is not ideal (I don’t remember them lol, its complicated), so having 2 organisms mix their genes to create a genetically unique offspring is extremely advantageous. Having 2 sexes is likely easier than doing this with a unisex species, but as another commenter pointed out: evolution doesn’t make sense, it just does what works.
Sexual reproduction is more advantageous than asexual reproduction because it makes genes more varied and prone to mutations and changes. If, for some reason, all beings of your species without characteristic “X” die because, for example, they do not have enough resistance to cold, in the end someone with resistance to cold survives because, through the mixing of genes and other factors, this advantageous characteristic has emerged and prevails.
Whereas in asexual species, everyone is born with almost the same genes as their parents, so if it starts to get very cold, eventually everyone dies because no one has developed resistance to cold, as it is rarer for this to happen.
PS: I am not an expert and I try my best to explain what I remember.
It seems to be the demands of large terrestrial mammals. Land is a harsher environment where more genetic diversity from sexual reproduction is more advantageous. Being larger and having longer lifespans makes asexual reproduction rarely advantageous. One parent needing to gestate the offspring would exacerbate the pressures for sexual dimorphism. Almost no mammals asexually reproduce, in fact it might actually be none, but I’m not sure.
I mean, it does, but the thing is successful reproduction of fertile offspring and the aiming process is randomly throwing while blindfolded and someone attacks your arm.
This does make me wonder why we aren’t uni sex, from an evolutionary point of view. Wouldn’t it be easier to reproduce?
This is an unresolved problem in biology. In general, evolution never makes sense. There is no inherent goal or optimization. If the individual is fit and adapted, it produces offspring. If not, it does not hand down its genes. There is no deeper process involved.
I mean, you could say there’s no inherent goal on anything, goals are always subjective/constructed, so from that perspective nothing ever makes sense.
But I think the question was how is it possible that sex differentiation could have contributed to make us fit and adapted even though in the surface it might seem to be more like an obstacle to reproduction (and thus, survival).
My guess is that specialization allows for higher level social structures that can more easily organize to survive. You have extreme cases with the bees, ants, etc. whose individuals can even have different sets of chromosomes and are very specialized for specific roles, making them so successful that you have them all over the planet for far longer than humans, millions and millions of years with hardly any changes.
But on the other hand, it is weird how sexual reproduction was selected for many times and rarely reverts back.
Like there are a lot of different modes of it in nature, species with more than 2 sexes, species that have 2 sex organs etc. but it does seem that somehow it gets selected for over alternatives.
Two parent reproduction leads to better adaptability. Asexual reproduction leads to the offspring being genetic copies of the parents, which is great if the parent fits well to the environment it is in, but any change to that environment could be catastrophic and lead to the species dying out. With two genetic sources, it allows for greater deviation in the species. So if there is a change in the environment, some will die, but there is a higher likelihood of some individuals being able to adapt better and survive in the changing environment.
I feel the question wasn’t so much about the sexual process (fusion of genetic information of two individuals) but about sexual differentiation (separation of this information into two parts) . At least, to me “uni sex” is not the same as “no sex”. These are different things, in biology you can find creatures that reproduce sexually but do not have sexual differentiation.
Yeah that’s one theory and it makes intuitive sense but if you read the link the person I responded to posted that doesn’t fully explain it and doesn’t necessarily have statistical backing.
Yes… the thing is that with asexual reproduction you can reproduce way more and much faster… so even though each individual division might have less variability, you have many more generations of splits and a bigger population that ends up being forced to spread around more to different conditions and eventually leading to mutations faster than they would have otherwise.
Also, the ease of reproduction makes each individual more disposable, and at that point it doesn’t make as much sense to have more mechanisms to protect your genetic material from mutagens, you can just let the mutants die when they are not fit and produce new ones until ultimately you hit the jackpot and achieve a new resistance. This is what makes bacteria so adaptable, with new strains appearing every day.
Strength in numbers?
While it’s not the reason we have 2 sexes, there is an evolutionary reason for 2 partners to make an offspring, which is likely a big contributing factor
While asexual reproduction is easier, the downside is that the child is almost an exact genetic match of the parent. There’s a lot of reasons why this is not ideal (I don’t remember them lol, its complicated), so having 2 organisms mix their genes to create a genetically unique offspring is extremely advantageous. Having 2 sexes is likely easier than doing this with a unisex species, but as another commenter pointed out: evolution doesn’t make sense, it just does what works.
Sexual reproduction is more advantageous than asexual reproduction because it makes genes more varied and prone to mutations and changes. If, for some reason, all beings of your species without characteristic “X” die because, for example, they do not have enough resistance to cold, in the end someone with resistance to cold survives because, through the mixing of genes and other factors, this advantageous characteristic has emerged and prevails.
Whereas in asexual species, everyone is born with almost the same genes as their parents, so if it starts to get very cold, eventually everyone dies because no one has developed resistance to cold, as it is rarer for this to happen.
PS: I am not an expert and I try my best to explain what I remember.
It seems to be the demands of large terrestrial mammals. Land is a harsher environment where more genetic diversity from sexual reproduction is more advantageous. Being larger and having longer lifespans makes asexual reproduction rarely advantageous. One parent needing to gestate the offspring would exacerbate the pressures for sexual dimorphism. Almost no mammals asexually reproduce, in fact it might actually be none, but I’m not sure.
because evolution doesn’t target some optimal thing
I mean, it does, but the thing is successful reproduction of fertile offspring and the aiming process is randomly throwing while blindfolded and someone attacks your arm.
what like via budding?
Via fucking just anybody, I suppose. Like those species which are hermaphroditic
There probably was a version of us that evolved to reproduce that way but the homophobes killed them off.
Ya exactly, I don’t really get why we evolved sexes. Im sure it’s just a Google search away later tonight when I have time.
Have a good read my dude
evolution doesn’t have a whole lot of “why”, just “oh look that happened”
Nature has Sequential Hermaphroditism as a thing.
Or just Hermaphroditism.