Questions about Evolution (yoinked from different thread...)

Zombrex

midlandsmissus wrote: »

I don't think there's meant to be a plan for evolution. I just don't understand. I thought evolution was about adapting to environment, survival of the fittest, and devoloping for the better.

Evolution is about keeping you alive long enough so that you reproduce, thus keeping the genes that produced you and your ability to survive long enough to reproduce ticking over for another generation.

If your genes were not able to keep you alive long enough to reproduce they disappear into the sands of time because with no children you have no one to continue your genetic line.

The fact that you go through your life in unbearable period pains is not relevant to this unless it some how stops you surviving or reproducing. And aside from the odd urge from the boyfriend to kill his girlfriend when she is on her period in general periods do not kill the woman.

iguana

midlandsmissus wrote: »

Anyway, believe me I don't feel like I need to prove my medical history to you. This is ridiculous! I find it more amazing that you are not even considering the heavy period/nothing wrong scenario a possibility.

I've edited that reply to include more info. As it happens I'm actually concerned about you, I have what's considered a "normal" heavy period and it never goes beyond 150ml. (I often double ovulate and my cycle can run to 6 weeks at a time.) I know too many women who have been fobbed off by doctors who are arrogantly dismissive about women who are experiencing real problems with their cycle and suffered needlessly for years/decades and two people I know eventually found out that their fertility was damaged by something preventable but undiscovered. Have you had blood tests? You may have a hormonal balance which is causing a lack of re-absorbtion. An ultrasound wouldn't have shown this up.

midlandsmissus

iguana wrote: »

I've edited that reply to include more info. As it happens I'm actually concerned about you, I have what's considered a "normal" heavy period and it never goes beyond 150ml. (I often double ovulate and my cycle can run to 6 weeks at a time.) I know too many women who have been fobbed off by doctors who are arrogantly dismissive about women who are experiencing real problems with their cycle and suffered needlessly for years/decades and two people I know eventually found out that their fertility was damaged by something preventable but undiscovered. Have you had blood tests? You may have a hormonal balance which is causing a lack of re-absorbtion. An ultrasound wouldn't have shown this up.

As I have edited mine, we just keep missing it before we reply .

If you check my post now, I added that I was getting periods every 2 weeks for a time aswell and was just put on the pill. I've often had such extreme pain aswell that I've literally been rolling around the toilet floor at work. I was told that this was normal. Thanks for your help, you've convinced me now that I should go back. I was really fobbed off the last time.

strobe

Galvasean wrote: »

Less talk about private girly stuff, MOAR monkies and dinosaurs! :pac:

https://www.youtube.com/watch?v=2Tt9P2qWfWg

Am I doin it right?

iguana

Galvasean wrote: »

Less talk about private girly stuff, MOAR monkies and dinosaurs! :pac:

Can we combine it? Bearded Emperor Tamarin monkeys have an interesting reproductive system. They ovulate twice per cycle and almost always give birth to fraternal twins. To get the optimal benefit from this female BET monkeys mate with 2 males during their fertile period. Then when the twins are born neither father knows which, if either, baby is his but must do all he can to help the mother and babies survive just in case one or both is his. The males form a love/hate relationship and must co-operate to help the mother look after her twins, each "father" taking one baby when the mother goes foraging. She indicates she wants them to come take the babies by sticking her tongue out at them.

That's good evolving!:D

Galvasean

midlandsmissus wrote: »

So is it that everyhing develops differently really due to it's environment?

Pretty much. Evolution basically responds to a need, so to speak. For example, when the climate/environment changes the individuals who are best suited to said environment survive and breed better than those less suited. The more suitable individuals pass their genes onto the next generation, so their traits which proved beneficial remain.
There is also what is refered to as an 'evolutionary arms race' where two interacting species basically (for a lack of a better phrase) 'try to out evolve each other'. Example; some herbivores start evolving thicker hides because it makes them less likely to be killed by predators, the predators in turn are evolving stronger jaws to bitethrough the thickening hides. Eventually you might have a new species of herbivore with strong armour (like an armadillo for example) being predated on by a predator with vice like jaws. In instances like this evolution is responding to a changing scenario, like changing climate except it is responding to other evolving creatures who interact with it.

strobe

iguana wrote: »

To punish us for that greedy, disobedient Eve woman who's apple eating was so heinous all her female descendants must suffer.:(

Well, apple thieves are worse than carcinogenic paedophile Hitlers, you have to admit.

midlandsmissus

Galvasean wrote: »

Less talk about private girly stuff, MOAR monkies and dinosaurs! :pac:

It is relevant anway.

Thanks very much for all your info Galvasean, it has explained alot to me, but it was actually Iguana who really got through to me there.

I don't know if I was thinking more intelligent design/evolution or what, but I always really hated it all, because as I've said, I've been in alot of pain for a large portion of my life, and I would think, "Why is evolution such a big pile of crap that I am just this lifeform here today going through so much pain for my whole existence". Is that what I have evolved to?

I lnow that probably doesn't even make sense from an evolution point of view, as in, "what's evolution ever done for me" , but coming from my point of view, it was holding me back.

That maybe I'm not meant to just put up with a random s%itload of pain just because I'm a woman, is helpful to me learning about evolution.

So thanks to the two of you.

Rockn

*this has probably been said because I started writing this reply aaages ago*
Evolution isn't "supposed to" do anything. Saying our early ancestors could have evolved into humans is silly because evolution doesn't plan ahead. It doesn't look to the future and say, "hmmm humans or apes, let's go for both!" When we reproduce we pass on our genes. There's a chance the genes can mutate which might lead to changes that benefit us (ie. help us reproduce). If it does then those genes will spread throughout the population ie. evolution happens. The kind of changes that would benefit us depend on our current environment, predators, competition etc. And those things change over time. What would have been good 10,000 years ago may not be much use now. So of course you end up with less than optimal animals. The reason we still have an appendix is because it would take a huge change for an entire organ to just disappear. And even if a person was born without an appendix it wouldn't be of much benefit to them.

Fur- Changes happen randomly and only stick around if they're useful at the time. It might be nice to have fur in cold climates and maybe gills if we live at the coast but we don't just get what might be good for us. There is no plan for the perfect animal. And there are always trade-offs. Peacocks, for example, have huge tails for courting but their tails also make it easier for predators to get them. So they've had to come to some balance between being eaten and getting laid (bad pun). Imagine if some people grew fur. It keeps them warm in the winter but maybe other people aren't attracted to furries and they have a hard time finding a partner. Hahaha. You've got to consider these other factors when deciding if some evolutionary change is good or not.

All animals you see are a work in progress, constantly being updated a tiny bit at a time. It's like looking at an old house that has had lots of work done over the years and asking, "why are there fireplaces in each room when it has central heating?".

You should read a good book on evolution like "The Selfish Gene". It would answer all your questions.



*mentally blocking out all the period stuff*

The Mad Hatter

midlandsmissus wrote: »

I think it's a very good question. Why would a common ancestor evolve into both apes and humans, when it could have just evolved into humans?

Because evolution never goes in a straight line.

Try to disavow yourself right now of the notion that we're "more evolved" than apes - we're not. We're smarter than them, certainly, but we'd have an extremely hard time living in any environment other than the very comfortable one we're used to.

robindch

midlandsmissus wrote: »

Really? But why design it that way in the first place?

It wasn't designed, it just happened that way.

midlandsmissus wrote: »

Why is there still an extreme amount of pain, when over the years scientific advances such as epidurals, should tell nature that pain is not needed in childbirth and is a hindrance?

Presumably because it's an unnecessary biological expense to have a pain system with an 'off switch'. Alternatively, not enough time has passed in order to evolve one, given that mums don't die from pain and the memory of the pain doesn't really seem to discourage them from having more kids (in fact, there appears to be an evolutionary mechanism which suppresses memory of the pain). In this case, there's simply no selection pressure to evolve a resistance to pain so it's probably never going to happen.

As I said above, evolution doesn't "care" about how much pain mums have during birth, nor how many mums and kids die overall, so long as a number sufficient to maintain the species don't die.

robindch

midlandsmissus wrote: »

Really? But why design it that way in the first place?

It wasn't designed, it just happened that way.

midlandsmissus wrote: »

Why is there still an extreme amount of pain, when over the years scientific advances such as epidurals, should tell nature that pain is not needed in childbirth and is a hindrance?

Presumably because it's an unnecessary biological expense to have a pain system with an 'off switch'. Alternatively, not enough time has passed in order to evolve one since birth began to be a significantly painful event. But given that mums don't die from pain and the memory of the pain doesn't really seem to discourage them from having more kids (in fact, there appears to be a biological mechanism which suppresses memory of the pain). In this case, there's simply no selection pressure to evolve a resistance to pain so it's probably never going to happen. Especially, since death rates are now very close to zero and birth rates are falling.

As I said above, evolution doesn't "care" about how much pain mums have during birth, nor how many mums and kids die overall, so long as a number sufficient to maintain the species don't die.

CerebralCortex

ColmDawson wrote: »

It's important to remember that evolution is not to be expected to have made us into some perfect species. Only traits that make us more likely to reproduce will be taken on. After reproduction, evolution 'doesn't care'. As a result, it'd be completely possible for us to evolve a trait that helps us reproduce when we're young, but also makes us likely to die at sixty years old instead of eighty.

Antagonistic pleiotropy I think it might be called.

liamw

Rockn wrote: »

You should read a good book on evolution like "The Selfish Gene". It would answer all your questions.

+1

midlandsmissus wrote: »

So is it that everyhing develops differently really due to it's environment? I can't think of the right questions to ask. Can you just tell me some other usefull things about evolution?

The problem is you still seem to be viewing evolution as some sort of conscious process. Evolution by natural selection is a blind process. There are no objectively 'good' or 'bad' mutations, this is merely subjective.

The environment drives the genetic drift. Adaptations get selected simply because the adaptation makes the individual more likely to reproduce.

One thing that everyone seems to be missing in this thread is that not all mutations are 'available' to a given species. I didn't think about this until I read 'The Extended Phenotype'. There are some limitations on what can evolve. So perhaps gene A persisted in the gene pool, not because it is better than gene B, but because B never had the potential to be a allele.

Sam Vimes

midlandsmissus wrote: »

Really? But why design it that way in the first place? Why is there still an extreme amount of pain, when over the years scientific advances such as epidurals, should tell nature that pain is not needed in childbirth and is a hindrance?

You seem to be under the impression that evolution should be recognising its environment and adapting to fit it, e.g. "learning" that child birth does not need to be painful from epidurals and so eliminating the pain. You've got it the wrong way around. The changes happen first and are completely random and the environment "tells" the organism if these changes are "good" or not by either killing it or not.
E.g. giraffes didn't grow longer necks because their genomes somehow recognised that there were good leaves on higher branches, random mutations gave some of them longer necks and these allowed them to get these higher leaves that their shorter necked brethren couldn't reach. Longer necked ones lived where shorter necked ones died, hence longer necked giraffes.

In the case of the pain of child birth, someone could be born one day who has a random mutation that makes child birth painless but with medical technology meaning that the people who have painful child births survive anyway, this new mutation doesn't give the woman any survival advantage and so the gene won't spread across the whole species. Her lucky off-spring will always carry the mutation and so have painless child births but the people who are unlucky enough not to have it will always experience pain.

The important point is that the existence of epidurals does not "cause" the evolution of painless child births; that's not how evolution works. We as a species would only evolve this trait when a random mutation gave one person the natural ability to have painless births and where this mutation gave the person a survival advantage that allowed the gene to spread

robindch

CerebralCortex wrote: »

Antagonistic pleiotropy I think it might be called.

New one on me -- thanks!

robindch

Sam Vimes wrote: »

Longer necked ones lived where shorter necked ones died, hence longer necked giraffes.

There's a new(ish) area of study in biology called epigenetics which is, broadly speaking, the study of how environment influences genetic expression - how individual genes get turned on or off by internal or external factors.

It seems that Lamarck might have been onto something after all, though the way it happens, and the levels of epigenetic influence are anything but clear.

nozzferrahhtoo

midlandsmissus wrote: »

I don't think there's meant to be a plan for evolution. I just don't understand. I thought evolution was about adapting to environment, survival of the fittest, and devoloping for the better.

Yes and no. Take your example of painful childbirth…

There is no mind or plan with evolution. It does not sit there and think to itself “Humans would be improved by pain free child birth” before it then sets to work on the task, scribbling on a drawing board with a thoughtful tongue sticking out of its mouth a little to one side.

Firstly, mutation etc has to hit on a change. Then that change has to be propagated successfully. Pain free child birth would not occur in one step, it would have to be many steps and each one of them would have to be selected for and maintained.

Ask yourself what kinds of changes would be required to achieve it. They are not insignificant changes and they could be anything from massive changes in the size of the head of the baby, or massive changes in the waist and hips width of human females, to many more things.

Each change would have to happen and be selected for without any plan or target to arrive at a conclusion of pain free child birth.

Against this background the changes in each step would have to either be beneficial or costless. Ask yourself what the “cost” of each change would be, in terms of the energy and behaviour of the creature caused by those changes. A massive increase in the waist or hip sizes of the human female would be very costly. Compare then these costs with the benefits obtained.

Many seemingly beneficial traits are lost for no reason if you do not consider the “cost”. A good example are sightless fish. Why did they lose their eyes? Surely having eyes is a benefit, even if 98% of your time is spent in environments so dark that you can not usually use them.

But no, the cost of maintaining eyes is high. You are more vulnerable to injury with them, the chemicals required to build and maintain them are complex, and that is just the eyes. The Brain is one of the most difficult to maintain organs, and the presence of eyes requires a brain to be maintained that can receive, process AND respond to the input from them. The “cost” of having eyes was higher than the benefit and so evolution removed the eyes.

The “cost” of our brains is high too, but the benefit we gain from them outweighs the costs. The brain has slowly enlarged and become more complex. This however has necessitated a change in gestation of children and has resulted in, among other things, a larger head at birth. This is where your pain comes from, and the “cost” of that pain is worth paying for the mental prowess we gain from our brains.

Your issue is you are thinking like a subjective designer. You think something is "better" and so evolution should do it that way. This is simply not how it works. There could be 1000 better ways to do something. This does not mean that A) evolution will hit on it or the cost of doing it the "better" way is beneficially proportional to the gain of doing that way.

nozzferrahhtoo

midlandsmissus wrote: »

What other species have common ancestors?

Well if you subscribe to the Theory itself then all species have common ancestors. It merely depends on how far you go back in time to find it. It is easier to go back to our common ancestor with other great apes for example than it is to go back far enough to find the common ancestor between yourself and the cucumber in your salad.

In the same way both you and I have common ancestors within the human chain we have common ancestors with every other living thing. If we were siblings then they would be our parents, but we are not. Go back enough generations however and we would find one.

The study and discovery of common ancestry is one of the most exciting in the study of biology. Common ancestors have been predicted, mocked in cartoons, and then discovered for real so many times. The most famous is the common ancestry between whales and land mammals. The cartoons of what a half whale half land mammal would look like were indeed very funny, but they dried up very quickly when just that very thing was found.

The power to predict those fossils before even finding them is one of the strongest sources of evidence for Evolution. Prediction is very important in Science and when you predict incredibly detailed things and then find them, it is a very strong support for your Theory.

Capt'n Midnight

midlandsmissus wrote: »

Why do we still have an appendix?

Why do we not have fur? - We are not suitbale to our climate

Why do women have periods? Evolution is supposed to be bettering traits that aid survival. Bleeding copius amounts for five days would attract predators no? Also, could the womb lining not just build up WHEN the egg is fertilised, is seems SO badly organised the way it is!

Why are so many born with serious defects, when evolution is meant to mean that genes which hinder survival become rarer?

Why is childbirth so dangerous, it would result in alot of deaths if not for the medical intervention we have now? Evolution is meant to ensure strength of reproduction.

Thanks!

appendix
at one stage they removed them from children while doing other surgery - they don't anymore because of the effects
if your gut gets flushed out because you have the runs the bacteria there can repopulate the gut later on

fur
we are one of the best long distance hunters on the planet, we can chase kangaroos , gazelle and other fast herbivores to exhaustion. being furless can have advantages in hot climates if you are are an endurance hunter
fur pattern is also good for short time in the water, we don't have water proof fur like otters, we have lots of fat compared to other primates more like seals really
climate is why we use clothes (a tool if you like)
patagonian natives could withstand extreme cold while being nearly naked, their body temps dropped more than other humans, people do adapt
I remember a case where an Icelandic trawler sank and the only person who survived was 22 stone, he was able to swim to shore because of the extra insulation

Like beavers and few other species we have a history of modifying the enviroment to suit ourselves in the short term, but groups of humans have evolved to meet local conditions.

and one reason why we may have lost fur is that we are born premature compared to other primates, furless and less facial development, this also means it's childbirth is easier than it would otherwise be

they've discovered apes in swamps that behave in a way that loosing fur and standing upright might be advantageous

there are people who are covered in hair on all their body

periods
pedators weren't really a big issue for animals that live in trees / groups / were top predators themselves - when food is in short supply they aren't an issue either
try attacking a female baboon and see how far you get - our ancestors were bigger , had larger groups and were much faster on the ground and could use water as an escape route too

defects
a lot of the older defects turn out to have some advantage
sicle cell anemia vs malaria
cystic fibrosos vs cholera
but more importantly from the view point of evolution it's only a defect if it stops those genes reproducing. One theory says that there is a genetic disposition to make people more attracted to men , if women have it they produce more children and that offsets the fewer children born to men who were more attracted to other men ( it's a theory )

childbirth
suppose the benefits of large brains and better benefits give a survival advantage over being stillborn

Overall
inheritable traits that don't reduce your survival or breeding potential won't be forced out.
if a gene is neutral then inheritance is random (attached ear lobes, colour of eyes, ability to wiggle ears , freckles - assuming they have no other effect)

you have to remember that evolution doesn't just mean nature red in tooth and claw , there are subtlier effects ,as Nietzsche said "that which does not kill me makes me stronger"

all the same it would have been nice to hang on to a decent sense of smell and a tail

keppler

midlandsmissus wrote: »

Why are so many born with serious defects, when evolution is meant to mean that genes which hinder survival become rarer?
Thanks!

I'll go out on a limb here and suggest that by birth defects you're referring to diseases too? If so, may i suggest you google 'recessive genes' it may at least answer part of you query

midlandsmissus wrote: »

Really? But why design it that way in the first place? Why is there still an extreme amount of pain, when over the years scientific advances such as epidurals, should tell nature that pain is not needed in childbirth and is a hindrance?

Seriously if you want to learn anything about evolution then i suggest that you learn to replace the word design with 'ad-hoc'.
As for pain, imagine a few reasons why you need pain to survive at all! then imagine you were giving birth in a time/place where modern medical science did not exist! how would you know if something was even wrong/complication with your birth??????
Evolution is not a conscious entity/being, it is not actually aware that modern medicine exists (that is not to say that modern medicine will not have an effect of some sort on evolution)

midlandsmissus wrote: »

Thanks for taking the time to reply, I see from this thread that people get annoyed to hear the "why do apes still exist so" question, but surely you should be happy to hear people asking questions? How else are you meant to learn except for asking questions?

I think people here appear to be getting aggrevated with you because you you are asking random questions about evolution but yet you do not appear to even know the basics (your putting the horse before the cart)
you may aswell be asking about calculus before you can even add or subtract.

if your really interested in learning yourself then may i suggest a good book to start with? The Greatest Show on Earth...Richard Dawkins.

Galvasean

keppler wrote: »

if your really interested in learning yourself then may i suggest a good book to start with? The Greatest Show on Earth...Richard Dawkins.

It's a good place to start. Not as in depth as his other books on evolution, but a very good place to begin for someone with little or no experience in the subject.

Jimmy444

keppler wrote: »

(your putting the horse before the cart)

Mind you don't upset the apple tart there, Bertie!

DeBunny

midlandsmissus wrote: »

Why do women have periods? Evolution is supposed to be bettering traits that aid survival. Bleeding copius amounts for five days would attract predators no?

Hmmm . . . where exactly did get this idea from?

https://www.youtube.com/watch?v=szFO7Wo7ZCE

sonicthebadger*

midlandsmissus wrote: »

I think it's a very good question. Why would a common ancestor evolve into both apes and humans, when it could have just evolved into humans?

Short answer: different environmental pressures in different habitat ranges of the ancestor species.

Humans are a funny kind of creature to look at from an evolutionary point of view because as soon as we got smart enough we started to change our habitat to suit ourselves which meant we spread all over the shop. Most animals cannot do that. Most animals have to spread by dying in their millions over several generations to adapt to a new habitat, often becoming either a new branch of the same species or (with enough time and distance isolation) a new species.

P.S. Please also note that "evolving into humans" wasn't the plan. Just being better suited to survival was the plan. The fact that the human format was suitable was sheer accident. In fact, I personally think and Octopus shape would have been way better, as would living underwater since most of the worlds habitat is water.

CerebralCortex

midlandsmissus wrote: »

I think it's a very good question. Why would a common ancestor evolve into both apes and humans, when it could have just evolved into humans?

Replication. You're still making the mistake of imposing agency onto the evolutionary process, which is a mistake.

darjeeling

robindch wrote: »

There's a new(ish) area of study in biology called epigenetics which is, broadly speaking, the study of how environment influences genetic expression - how individual genes get turned on or off by internal or external factors.

It seems that Lamarck might have been onto something after all, though the way it happens, and the levels of epigenetic influence are anything but clear.

I think we've yet to see over how many generations these epigenetic changes can persist. There's some evidence to say that they can last a few in some cases, but I think overall that hard-coding of information in the genome is far more significant in evolutionary terms.



It looks to me that the genome has evolved to evolve. Our concept of what a gene is has changed significantly, and we can now detect all kinds of strange activity in the cell, with unexpected bits of DNA being modified and copied into RNA. Some of this activity reflects sophisticated, evolved control systems that we're just beginning to unravel. Other activity may be tolerated random noise that might in future generate something evolutionarily useful - we don't yet know.

I also think that higher (complex, multicellular) organisms are sophisticated ways of coordinating genes that evolved in much simpler ancestral organisms. Potential for evolution in simple, unicellular bacteria, yeasts etc. is enormous, given the massive numbers and short life cycles of these lifeforms. In contrast, potential for evolving new genes in, say, humans is much lower. Instead, complex organisms have relatively few mutations that change the proteins themselves (compare, say, chimps & humans), and rather more regulatory changes that lead to a bit more of one protein being made and a bit less of another etc, etc.

GO_Bear

But a Tornado will never blow through a junk yard and form a fully functional Boeing 747

MrPudding

GO_Bear wrote: »

But a Tornado will never blow through a junk yard and form a fully functional Boeing 747

Clearly. Have you ever seen a tornado use a torque wrench?

MrP

sensibleken

If evolution is driven by mutation, how come we aren't all out boinking x-men? Is it because wolverine can't put on a condom without ripping it?