It's Friday, so I guess this topic is fitting. It's science, not political, though.
Why was sex developed? Why didn't we just continue cloning ourselves?
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It's Friday, so I guess this topic is fitting. It's science, not political, though.
Why was sex developed? Why didn't we just continue cloning ourselves?
What would the world be like without lewd jokes?
I mean cloning jokes might catch up in time, but they'll never be as funny.
Because DNA-technonoligy is kinda new, and it's a whole lot of fun?
I think HoreTore is referring to cloning as bacteria and other single cell organisms do it while so-called higher life forms seem to have developed from that to sex.
I guess the answer is that cloning the entire human body just like that would:
a) use a whole lot of resources at once, or take a veeery long time while you have to run around with a half-finished clone attached to your body.
b) be very complicated, apparently cells can only duplicate themselves, not duplicate a different cell, so your brain cells would have to clone themselves(IIRC brain cells can't clone/renew themselves like other cells anyway) and then the cloned cell would have to get to the appropriate spot in the unfinished clone body.
Sex works around all this by just transferring required information into a single basic cell which then clones and transforms to build a new organism based on the basic information provided. The advantages are:
a) Only during the initial state does it require additional resources, afterwards the new organism can sustain itself (by eating), the weight is also kept to the minimum required until the new organism can carry its own weight.
b) the complexity is mostly handled by the new organism itself based on the given information. The previous body does not have to coordinate the buildup and placement, the new body does this by creating a small blueprint that then grows independently.
I would conclude sex is nature's way to handle the complexity of so-called advanced organisms.
except there are complex life forms which can reproduce asexually - if you think about it there is no reason the Human body couldn't reproduce asexually right now - all it needs is for the body to produce both sperm and eggs for self fertilization (quite a few species of plant actually do this)Quote:
Originally Posted by Husar
the answer is actually considerable more complicated - it is about Genetic Variance and how sexual reproduction produces offspring with far greater genetic variance which allows for far more mutations which in turn allows a species to adapt more successfully to changes in environment
Why does sex exist?
Evolution baby!
If I'm a successful male and you're a successful female we can merge our genetic code and get the good qualities of both of us.
If you're cloning yourself, you're just making more copies of yourself and the only change could come from mutation. It's a lot slower of a process and we'd be a lot less adaptable.
This is the worst sex thread ever. ~;)
How is a babby formed?
Nah, evolution also occurs in asexual species. (You just reduce genetic drift, and a couple of related phenomena, but nothing so drastic that you need to invent a Y-chromosome and give half the species an inability to birth.) The more proximate cause?Quote:
Originally Posted by Xiahou
Looks like all of that bumping and grinding is due to ...
... parasites.
We were able to conduct a controlled test showing that exposure to coevolving parasites led to extinction of populations that could only self-fertilize, while populations that could have sex were able to survive and even adapt to the coevolving parasites. [...] we were also able to show that self-fertilization was favored by natural selection when no parasites were present and when parasites were present but not coevolving with the hosts. So, we were able to isolate coevolving parasites as a factor that maintain high levels of sex in populations that can either have sex or self-fertilize.
No, you're wrong. If you have an egg and a sperm, you're still not cloning anything, it's just a more boring version of sex for species that do not need the additional motivation. ~;)Quote:
Originally Posted by Sir Moody
Yes, I wanted to include genetic diversity and then I forgot about it over trying to make it sound as much like an engineering topic as possible.Quote:
Originally Posted by Xiahou
a species that reproduces asexually will have a lower genetic diversity than one that reproduces through sex.
when situations get tough from a survival standpoint, the population with a higher generic variability will have a better chance of surviving.
Sex, much like Mitt Romney, is the Great Job Creator.
The answer is 69.
Spoiler Alert, click show to read:
Quote:
Originally Posted by Xiahou
Yeah. I am on to him he wants to transcend the human race.Quote:
Originally Posted by Gelatinous Cube
I linked to the most current research on the subject, don't really know why it's being ignored.
Y'all should get on your knees and thank ringworms and malaria plasmodia for spanky sextime. 'Cause it sure looks like the energy and population division brought about by sex simply would not be worth it if it weren't for the hangers-on.
This is the greatest and most valid anti-scientific argument ever.Quote:
Originally Posted by Gelatinous Cube
That is not an explanation for sex as we, humans, know it. That's an explanation for sexual reproduction (pollen, flowers, etc.), but not "spanky sextime". The explanation for "spanky sextime" is efficiency: it's vastly more efficient to inseminate directly than leave things to chance...Quote:
Originally Posted by Lemur
Yeah, the reason I posted this is because of reading such an explanation. And I can accept that explanation just fine, it makes sense. I do have a problem with it, however, which I'm hoping for help to understand:Quote:
Originally Posted by Lemur
If sex gives an advantage over parasites, how has the species who clone themselves(fish, plants) survived? Why haven't they gone extinct?
Quote:
Originally Posted by HoreTore
Just because sex has an advantage doesn't mean all non-sexytime species should be extinct. You are dealing with absolutes, which is not necessary in this case. Plus, Sexytime mammals have no need to compete with fishies and plants that clone themselves.
What kind of fish clone themselves? All the fish I am aware of use insemination of eggs, even if it's outside the body.
Duh. The Clonefish. You need to get out of the house, broQuote:
Originally Posted by Husar
Every organism has a reason for existing, ie. they have beaten extinction somehow. I'm wondering what the organisms who reproduce through cloning has done to avoid extinction.Quote:
Originally Posted by Major Robert Dump
A specie of Stickleback is given as an example in the book I'm reading.Quote:
Originally Posted by Husar
Extinction is what happens when a species cannot adapt to changing conditions quickly enough to survive. This means there is more than one way to avoid it, and paradoxically the most common one is to not be confronted with it.Quote:
Originally Posted by HoreTore
HEY SPEAKING OF PARASITES AND SEX, HAVE I TOLD YOU ABOUT MY EX WIFE????
....And what I'm interested in is what those other ways are.Quote:
Originally Posted by Tellos Athenaios
How has a fish survived contact with parasites(who are practically everywhere in the water) without developing genders, which is the way almost every other non-microscopic organism has dealt with them?
And why did almost every other specie on the planet choose sex instead of whatever other option there is to combat parasites?
Despite all its advantages, sexual reproduction has one obvious disadvantage: it adds an internal evolutionary process, sexual selection. It's no longer good enough to be fit and clever; to adapt well to the environment. You also have to seek out another specimen of the opposite sex and successfully reproduce with it; typically involving a screening process where specimens may reject one another as mating partners; were some (or many) specimens might not get to reproduce at all.
It'll probably make the species more vulnerable to environmental change as the concept of what makes an attractive mate has to readjust to the new reality (through natural selection, of course).
But apparently the advantages to sexual reproduction are too big for this to matter.
No, plenty of plants and animals reproduce sexually without sexual selection in that sense (think grasses, corals, etc.). Sexual selection occurs with direct insemination, and direct insemination is such a major improvement in efficiency that it is worth the hassle of sexual selection. Additionally direct insemination is also by far the best bet for sexual reproduction in arid regions because it compensates for the primary drawbacks of sexual selection (the risks from exposure to a hostile environment for eggs and sperm).Quote:
Originally Posted by Viking
As far as numbers are concerned asexual beats out ;) sexual reproduction
Frequency is one of the factors. Bacteria from a human point of view are constantly dividing. Sure each event has a smaller drift than sexual reproduction. But they divide so many times in a short period of time it adds up.
Species that can both sexually and asexually populate based on how rapidly the environment is changing. Essentially they clone in a stable environment and sexually reproduce in an unstable one.
True, but there is still sexual selection in terms of efficiency in e.g. pollination.Quote:
Originally Posted by Tellos Athenaios
As I understood it, sex gives a controlled mutation, and also better mutations more often.
If we talk about penetrative sex, it was a advantage to be able to take care of the fosters inside the body, so they are less shark food when they get born.
And as a sidenote: Sex exist because it's DAMN fun. I don't think the first fish who penetrated anther fish ever went back to the alternative..
The first female fish to be penetrated must have been in for quite a shock though.