Evolution

antijoke · 14 Jul 2009 at 09:00

So I was watching 'Inside Natures Giants' last night on C4 and it got me wondering about evolution.

Do you think we will see evolution happening in any of the species alive today?

Greebo · 14 Jul 2009 at 09:04

Normally happens over such a long period of time that we wouldn't notice in our lifetime.

Fenris · 14 Jul 2009 at 09:05

Well think about it, over the last several hundred years the human race is doing two things, growing taller and living longer, thats evolution right there. It's just not very interesting and most people don't tend to care unless the headline reads "Baby born with extra arms".

Raymond Lin · 14 Jul 2009 at 09:05

It's happening in front of your eyes but you don't live long enough to see the difference.

antijoke · 14 Jul 2009 at 09:10

But what about the species that have been around far longer than us?

Take crocodiles for example, have they reached the end of their evolution?

Sparky__H · 14 Jul 2009 at 09:12

Fenris said:
Well think about it, over the last several hundred years the human race is doing two things, growing taller and living longer

Actually both of those can be more strongly attributed to to change in diet and advances in medical technology. We have grown taller since our greater ancestors (10 thousand years) but not by much.

And Evolution is not something you can see unless your extremely fortunate to see some mutation occur which causes further propagation. It would obviously have to be a creature with a short breeding cycle of course.

anticonscience said:
But what about the species that have been around far longer than us?

Take crocodiles for example, have they reached the end of their evolution?

Seeing as how the program already explained how the crocodile has branched out into separate sub-species you know that not to be true.

stinamoo · 14 Jul 2009 at 09:20

*deleted*

antijoke · 14 Jul 2009 at 09:27

I guess I wasn't very clear in what I said and what I meant about the 'end'.

Jamesdavid3 · 14 Jul 2009 at 09:27

evolution happens all the time, but it happens so slow we cant see it.

stinamoo · 14 Jul 2009 at 09:33

*deleted*

int · 14 Jul 2009 at 09:34

Bacteria.

Makunouchi · 14 Jul 2009 at 09:39

anticonscience said:
Do you think we will see evolution happening in any of the species alive today?

have they reached the end of their evolution

I don't think you've understood what evolution is...

antijoke · 14 Jul 2009 at 09:43

stinamoo said:
What do you mean by 'end' then? Species continue to mutate and evolve until they become extinct (or sufficiently different enough that we call them a different species).

I was thinking more along the lines of them not needing to evolve anymore.

Makunouchi said:
I don't think you've understood what evolution is...

That's very possible, but from reading that link that was posted I do have a better insight into what it is.

Sparky__H · 14 Jul 2009 at 09:44

anticonscience said:
I was thinking more along the lines of them not needing to evolve anymore.

You can reach a stage where mutation cannot be a positive (Cant improve on the base model) so said mutation dies out.

Greebo · 14 Jul 2009 at 09:49

Problem is that evolution normally is a reaction to environment and since our environment is changing, crocodiles will still continue to evolve.

The problem some scientists foresee is that if the environment changes too quickly then species will not be able to evolve quickly enough and will die out. Normally these changes take place of 1000's of years.

Idiot example for you. Say over the next 20 years, trees suddenly started to be twice as high as they are now. Giraffes could not evolve a longer neck in time and would lose one of their major food sources. Silly example I know but you get the point.

Makunouchi · 14 Jul 2009 at 09:49

anticonscience said:
That's very possible, but from reading that link that was posted I do have a better insight into what it is.

Just taking the two lines I quoted: evolution is happening constantly, it's a natural process that has no 'end' and no 'beginning' (and also no will of it's own). Evolution isn't forcing us towards some form of 'perfect being', so a crocodile isn't 'complete', even though it's basic shape hasn't changed for hundreds of thousands of years, it's still evolving (or it could be an evolutionary dead end and will die out over time, to be replaced by something else).

Edit: although human interference means the future of lots of species are no longer natural governed.

Tefal · 14 Jul 2009 at 10:00

Sparky__H said:
And Evolution is not something you can see unless your extremely fortunate to see some mutation occur which causes further propagation. It would obviously have to be a creature with a short breeding cycle of course.

E-coli has been seen to "evolve" (i'm sure nitefly will kill me for this) the ability to digest citrate in one experiment through random mutation.

one of e-coli's defining characteristics is it cannot normally digest citrate.

Moley · 14 Jul 2009 at 10:05

Greebo said:
Idiot example for you. Say over the next 20 years, trees suddenly started to be twice as high as they are now. Giraffes could not evolve a longer neck in time and would lose one of their major food sources. Silly example I know but you get the point.

It's actually a perfectly good example because the giraffes would be forced to change their habits or die out. What is likely to happen in this instance is that some of the giraffes would start eating the bark of the trees instead of the leaves. They may also start eating the juvenile trees before they grow too tall.

There are several potential results out of this - the juvenile trees get killed off and eventually that species of tree dies out. Evolution affects plant life too remember.

Also the giraffes that start to eat bark will adapt to their change in diet - albeit slowly.

Those that don't change will die out - survival of the fittest in action.

Sparky__H · 14 Jul 2009 at 10:06

Tefal said:
E-coli has been seen to "evolve" (i'm sure nitefly will kill me for this) the ability to digest citrate in one experiment through random mutation.

one of e-coli's defining characteristics is it cannot normally digest citrate.

Yeah a generational mutation in a rapidly reproducing organism. I'd say that the guy was fortunate

Tefal · 14 Jul 2009 at 10:07

Sparky__H said:
Yeah a generational mutation in a rapidly reproducing organism. I'd say that the guy was fortunate

iirc the experiment was going on about 20 years before it happened.

Also only some batches (it was grown the separated every so often and some frozen) evolved that way, many didn't get the right combination and just became slightly different ecoli.