Ask me any questions you have about evolution

reply to post by JenRae93

Originally posted by JenRae93
reply to post by madnessinmysoul

 

Well, it does have to do with the theory of evolution, in that it's the only origin theory that relies in the "big bang" as an explanation for how the hydrogen got here

Um...no, it doesn't.
Evolution is not an origin theory, it's a biodiversity theory

Evolution would remain unchanged by the source of life. Life could be the product of a giant sombrero with magical powers and evolution would still be true.

Little bit late, I was avoiding ATS for a while

Originally posted by purplemer
what is allowing evolution to take place.

Genetics, mostly. Sexual reproduction helps, but isn't strictly necessary.

What causes the shift from disorder to order.

Actually Evolution is a process of increased disorder. The more generations, the more mutations, the more species, then the more genuses. All through it things are living, dying, breeding, eating, surviving, crapping, drinking, and making who knows how many smells and sounds.

A point of perfect order would be a lifeless planet, or a planet with only a single unchanging species, each following the exact same outline as those that went before... which isn't very "lively," is it? They'd probably qualify more as a form of mineral.

I understand you're trying to shoehorn the laws of thermodynamics into this subject - I've seen it often enough. But nowhere on earth will you find the "closed system" needed for the entropic decay found in those laws.

Evolution is a process and that process requires movement.

Or at least some form of dispersal.

Science is a belief system not unlike religion. Its puts your view of the universe in a box.

It can be called a "belief system," insasmuch that I believe that if I do something (say, mixing baking soda and vinegar) and get a result (a moment of froth as carbonic acid is formed, decays, releases carbon dioxide and leaves a solution of sodium acetate and water,) and 999 other people do the exact same thing to get the same result, then it's my belief that the 1001st person, doing the same thing, will ALSO get the same result.

Religion is believing that I and nine hundred and ninety-nine other people can mix baking soda to get carbon dioxide and a water / sodium acetate slush, but that the 1,001st person might produce a mouse. To a religious mind, each of these chemical reactions is a unique and independently-created reaction devised at the whim of some other being. Therefor I might get CO2 / H2O+NaOAc in my science experiment, but if god wills it, performing the experience might set YOU on fire, and madnessinmysoul over there might get a chemical that turns everything it touches into bacon.

Science is very much unlike religion.

Cannot you not see the limitations of science, when the one thing science cannot prove is the existence of consciousness.

And what makes you think consciousness is real? Much like the flat earth, geocentrism, and the thought that the heart is important to emotions, consciousness is actually an illusion caused by our limited awareness of our own existence - which is kind of ironic, but true. If we had full awareness of our own bodies, then what we call "consciousness" would be exposed as nothing more than a fairly random pattern of chemical secretions and reactions with resultant electrical charges.

Think of it this way. Our consciousness is like this picture:
blogs.riverfronttimes.com...
To our perception, it's a coherent picture of a puppy.
In reality it's several million colored dots that are produced by a layer of molecules aligned between two transparent electrodes and two polarizing filters, the axes of transmission of which are (in most of the cases) perpendicular to each other, all backlit with a fluorescent light. (At least for me, dunno if you use a LCD monitor)

Why do you see a puppy instead of a blob of colored dots? Or a spray of angled photons? because it's easier for your brain to handle that that blob of dots resembles a puppy, when in fact it looks NOTHING like a puppy. It's your brain taking a shortcut, arranging the information it's receiving from your eye into something that might be useful to you, and therefor you say "Awwww, cute puppy!"

In the same way, it's easier for our minds to handle the concept of "consciousness" rather than acknowledge the chemical and electrical reactions that are really going on; pay attention to the great and mighty Oz, not all the technicians, actors, grips, set producers, casting directors, special effects guys, and editors behind the curtain.

The only thing you truly know to exist.... your consciousness. Science cannot prove
Does that not tell you something.

It tells me you have a weak understanding of both science and consciousness, yes.

I was just wondering:
what did "Adam" and "mitochondrial Eve" look like, and what lines descended from each of them?

Yes, I am aware that they lived at different times.

reply to post by Kailassa


We don't know what Y-chromosomal Adam and Mitochondrial Eve looked at....and the answer is everyone.

Everyone is descended from Mitochondrial Eve and all men are descended from Y-chromosomal Adam

reply to post by madnessinmysoul


Thanks, Madness, but I meant what other homo genuses were descended from them?

Were Peking Man, Neandertals and/or other homo genuses also descended from them?

reply to post by Nosred


Why does the brain transmit out and act like a reciever?

What purpose would that have in evolution?

reply to post by andy1033

Originally posted by andy1033
reply to post by Nosred

 

Why does the brain transmit out and act like a reciever?

It doesn't.

What purpose would that have in evolution?

Guhhhhhhhh

Basic ignorance of evolution....
Evolution doesn't involve a 'purpose' it involves advantage vs disadvantage vs neutral.

In this case, if the brain acted in the fashion you just mentioned (it doesn't) it would be a huge communication advantage.

reply to post by Kailassa


First off, Homo is the genus for all of these. You want species. As in, Homo sapiens or Homo eregaster or Homo habilis.

Second, no. Both Mitochondrial eve and Y-Chromosome Adam were Homo sapiens, and at least Y-Adam was certainly a fully modern model of the species. They both existed too recently to be ancestral to other Homo species, and it's unlikely even that descendants of M-Eve mingled with H. sapiens neanderthalensis "in that way" simply becausee of the difference in ages - the neandertals were already on their last legs in italy and Iberia by the time M-Eve's descendants started spreading out.

Originally posted by TheWalkingFox
reply to post by Kailassa

 

First off, Homo is the genus for all of these. You want species. As in, Homo sapiens or Homo eregaster or Homo habilis.
Second, no. Both Mitochondrial eve and Y-Chromosome Adam were Homo sapiens, and at least Y-Adam was certainly a fully modern model of the species. They both existed too recently to be ancestral to other Homo species, and it's unlikely even that descendants of M-Eve mingled with H. sapiens neanderthalensis "in that way" simply becausee of the difference in ages - the neandertals were already on their last legs in italy and Iberia by the time M-Eve's descendants started spreading out.

Thanks, WalkingFox.

All humans today carry mitochondria that can eventually be traced back to "Eve".
Most humans today carry dna inherited from neandertals. (3/4 or so?)

If the intermingling with neandertals took place before Eve and we got their DNA through her, wouldn't all humans have it?

I'm still thinking, trying to work this out.
How do we achieve:
1. pre-Eve genetic mingling with neandertals
2. all living humans descended from Eve, and
3. most but not all humans today having some neandertal DNA?

Perhaps males whose lineage included neandertals mated with females descended from Eve?

I'm not out to prove any point, just trying to understand.

Originally posted by Kailassa
Thanks, WalkingFox.

All humans today carry mitochondria that can eventually be traced back to "Eve".
Most humans today carry dna inherited from neandertals. (3/4 or so?)

It's estimated around 1% to 4%, for some modern human populations. Most Africans lack any such traces, and I imagine southern and eastern Asia are also void of any neanderthal background. It's also possible that the 1-4% estimate is an error - contamination of the Neandertal DNA is always a possibility.

If the intermingling with neandertals took place before Eve and we got their DNA through her, wouldn't all humans have it?

I'm still thinking, trying to work this out.
How do we achieve:
1. pre-Eve genetic mingling with neandertals
2. all living humans descended from Eve, and
3. most but not all humans today having some neandertal DNA?

Perhaps males whose lineage included neandertals mated with females descended from Eve?

I'm not out to prove any point, just trying to understand.

They've actually found that any mingling with Neandertals was between neandertal males and modern women - at least any surviving family lines have that arrangement. There are no neandertal mitochondria among human populations, meaning nobody's mother was a neandertal.

UFCS article

Originally posted by TheWalkingFox

Originally posted by Kailassa
Thanks, WalkingFox.

All humans today carry mitochondria that can eventually be traced back to "Eve".
Most humans today carry dna inherited from neandertals. (3/4 or so?)

It's estimated around 1% to 4%, for some modern human populations. Most Africans lack any such traces, and I imagine southern and eastern Asia are also void of any neanderthal background. It's also possible that the 1-4% estimate is an error - contamination of the Neandertal DNA is always a possibility.

I was asking what proportion of humans carry neandertal DNA when I queried 3/4.
I was not suggesting 3/4 of our DNA was neandertal.
Sorry for the ambiguity.

If the intermingling with neandertals took place before Eve and we got their DNA through her, wouldn't all humans have it?

I'm still thinking, trying to work this out.
How do we achieve:
1. pre-Eve genetic mingling with neandertals
2. all living humans descended from Eve, and
3. most but not all humans today having some neandertal DNA?
Perhaps males whose lineage included neandertals mated with females descended from Eve?

They've actually found that any mingling with Neandertals was between neandertal males and modern women - at least any surviving family lines have that arrangement. There are no neandertal mitochondria among human populations, meaning nobody's mother was a neandertal.

UFCS article

That makes sense.
I'd read speculations that the most likely way was through the horny Homo sapiens spending time with the neandertal women, but I couldn't see how that made sense genetically.

Thanks.

reply to post by Kailassa


On that latter point... Well, that's a bit of cultural bias. Even in this day and age, society can have difficulty accepting the notion of "our" women with "their" men - no matter who "us" and "they" are.

Though truthfully, it does make you wonder. Historically with our species, it's always been the men who go over yonder, grab a wife that's handy, then call the rest of the family over if the eating's good. This is because in our species, like most others, male are expendable - you only need a rather small number for breeding purposes.

So, were excess neanderthal men doing the same thing as we do? I know a few women who would love to get with a barrel-chested man who can out-wrestle a grizzly, so it's not too far-fetched.

Originally posted by TheWalkingFox
reply to post by Kailassa

 

On that latter point... Well, that's a bit of cultural bias. Even in this day and age, society can have difficulty accepting the notion of "our" women with "their" men - no matter who "us" and "they" are.

Though truthfully, it does make you wonder. Historically with our species, it's always been the men who go over yonder, grab a wife that's handy, then call the rest of the family over if the eating's good. This is because in our species, like most others, male are expendable - you only need a rather small number for breeding purposes.

So, were excess neanderthal men doing the same thing as we do? I know a few women who would love to get with a barrel-chested man who can out-wrestle a grizzly, so it's not too far-fetched.

IMO cultural patterns and inclinations can be just as much part of evolution as genetic changes are. But then I believe that genes, or the expression of them, influence behaviour more than is generally realised. That's not to say we don't have freedom of choice, just that there is pressure in certain directions.

It can't be denied that some humans have an urge to experiment sexually, and there's no reason to assume that urge was not in existance in those time. There's also a tendancy of the group as a whole to reject other groups. So I'd expect some interbreeding to go both ways, when individuals thought they could get away with it.

We know that with animal breeding, mongrels tend to be tougher and healthier.
The same goes for humans, apparently:

Pill Users Choose 'Wrong' Sex Partners
Animal studies show that female mammals can smell out males whose MHC genes are different from their own. MHC genes affect important immune responses. By mating with males who have different MHC genes, females give their offspring a better disease-fighting repertoire.

It's true of humans, too. In laboratory studies, women who sniff men's sweaty T-shirts find them more attractive when they come from men whose MHC genes don't match theirs. It's not that certain MHC genes smell better to women -- it's the difference that counts.

So it's possibly that a bit of mingling with the natives has left the human race rather more robust than it would be otherwise, and this could also have left us genetically inclined to continue such experimentation.

If aliens ever land here, you can be sure that whatever they looked like, there'd be humans of both sexes lining up for some Wookie nookie.

reply to post by Kailassa


Being a product of such a pairing, and being quite inclined to continue the trend, I agree fully.

Interesting about the sweat, though. I wonder if it works in similar ways intra-sex. Like, are guys more comfortable with similar scents, with the "foreigner" spurring some territorial reaction? I have my own anecdotal evidence, but I'm not inclined to do rigorous testing.

Originally posted by TheWalkingFox
reply to post by Kailassa

 

Being a product of such a pairing, and being quite inclined to continue the trend, I agree fully.

Inter-racial or inter-planetary?

Interesting about the sweat, though. I wonder if it works in similar ways intra-sex. Like, are guys more comfortable with similar scents, with the "foreigner" spurring some territorial reaction? I have my own anecdotal evidence, but I'm not inclined to do rigorous testing.

You're suggesting that similar scents could lead to group bonding?
That could be advantageous, as loyalty and chivalry would help for the survival of the group.
And humans, being physically vulnerable, must have done a lot more of their surviving as groups than as individuals. Die defending a group, and (some of) your genes will most likely survive within the group. Die as a loner or small family and your genetic inheritance is likely to die with you.

However I'd expect the bonding to be with familiar scents rather than with similar scents. Or perhaps with both.
This could explain the way women living in close proximity tend to synchronise their menstruation.

hmm... Bonding seminars used by some businesses, perhaps the more they make everyone sweat together, the better they work.

Double hmm... Perhaps all the scents women wear are responsible for the competitive gut-gouging bitchiness too many women show toward each other. In the hippie days it was just a dab of patchouli or sandlewood, and women were all sweet and supportive. - well, not actually, but perhaps a bit moreso than these days.