Interesting Topics on Evolution

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eeyonkee

Trad climber

Golden, CO

Topic Author's Original Post - Jan 1, 2013 - 12:41pm PT

First of all this is NOT a thread about whether evolution is true or not. The starting point for this thread is it is. That being said, there are lots of interesting issues within this very big topic that are controversial and thought-provoking. It's clear to me that there are lots of very bright STers with a range of scientific backgrounds that could make this fun. Here are three topics that I've been interested in for several years.

1. Are humans still evolving? I mean significantly. Are we going to continue evolving bigger brains for instance. Since natural selection requires some sort of selection pressure, typically involving either a significant culling or isolation of a population, is this likely in a world of 7 billion where people move (and procreate) freely across the planet?

2. Is group selection, as advocated most notably by the evolutionary biologist E.O. Wilson, a viable process for explaining things like altruism or can this be explained entirely by selection at the organism or gene level?

3. What is the likelihood that the emergence of life on a planet will lead to intelligent life given 100s of millions or billions of years of evolution to work with.

My short opinions are (1) No. (2) No. (3) Low. I could be wrong on all three.

Jaybro

Social climber

Wolf City, Wyoming

Jan 1, 2013 - 12:58pm PT

1) yes, because I don't think it can, stop. Esp with a population and number of variables as high as what we have.

-but it's hard to tell from the inside what the pressures are that are pushing evolution and what mutations are being favored. Probably something like immunity to an upcoming plague. Or nimble texting fingers, or other hand eye coordination factor.

2) need more data

3) low but inevitable, eventually.

darkmagus

Mountain climber

San Diego, CA

Jan 1, 2013 - 12:59pm PT

1. Yes, I think our current "form" has only existed for a relatively short period of time. I think there are some things that have changed even over that short period (like average human height). Maybe different genes are turned on by different/changing factors in the organism's environment.

2. Maybe this is in the domain of something else, like memetics? Although I do think certain aspects of human behavior are fairly "hard-wired" In cases.

3. I also think low. But I would change it to "low-to-medium" if I knew that there were many more potential life-harboring planets verified to exist and were stable over long periods. I always have the feeling that if we could access a "god's eye view" of all life in the universe, we might be very surprised at how much of it there is.

Phantom X

Trad climber

Honeycomb Hideout

Jan 1, 2013 - 01:02pm PT

Please pass the bananas. Happy New Year!

John Butler

Social climber

SLC, Utah

Jan 1, 2013 - 01:06pm PT

4. Social media leads to devolution. :-)

eeyonkee

Trad climber

Golden, CO

Topic Author's Reply - Jan 1, 2013 - 01:14pm PT

I hope the whole idea of three topics doesn't make this too messy...

Jaybro, with respect to 1), obviously the processes behind evolution have not changed, and clearly genetic drift will always occur, but for something significant like bigger brains you need something like smart people preferentially procreating with other smart people AND out-procreating the rest of the population. I just don't see it. In fact the large population would tend to inhibit rather than advance evolution.

mcreel

climber

Barcelona

Jan 1, 2013 - 01:22pm PT

Here's an article that discusses the relationship between population growth and selection:

http://www.dailygalaxy.com/my_weblog/2011/05/human-hyper-evolution-have-mutations-changed-the-course-of-history.html

A quote:
"Five thousand years is such a small sliver of time -- it's 100 to 200 generations ago. That's how long it's been since some of these genes originated, and today they are in 30 or 40 percent of people because they've had such an advantage. It's like 'invasion of the body snatchers.'"

eeyonkee

Trad climber

Golden, CO

Topic Author's Reply - Jan 1, 2013 - 01:28pm PT

Great article, McCreel! I think I have to change my answer to 1.

I just read an old Scientific American article on topic 3 about SETI. The original proponents, largely physicist predicted that the probablity would be close to 100%. Evolutionary biologists then chimed in and suggested that this was a complete misunderstanding by the physicists on how evolution really works. There's nothing particularly inevitable about it.

Ed Hartouni

Trad climber

Livermore, CA

Jan 1, 2013 - 01:31pm PT

http://en.wikipedia.org/wiki/Evolution

1) http://en.wikipedia.org/wiki/Human_evolution#Recent_and_current_human_evolution

2) http://en.wikipedia.org/wiki/Sociobiology
http://en.wikipedia.org/wiki/Evolutionary_anthropology

3) http://en.wikipedia.org/wiki/Evolution_of_human_intelligence
http://en.wikipedia.org/wiki/Behavioral_modernity

mongrel

Trad climber

Truckee, CA

Jan 1, 2013 - 02:05pm PT

Moosedrool is right on the money.
1. Yes, unquestionably evolving, but perhaps not how you are thinking. Evolution is just change in frequencies of genetic variations that code for phenotypic (observable) traits. It's directional to the extent that those traits result in the leaving of greater numbers of offspring in future generations whether through getting more food, avoiding getting eaten, or just having more offspring that survive (and then getting eaten). Sharp eyesight once conferred an advantage in survival; now, not so much. So the genetic combinations that produce it are less prevalent than they used to be: voila, evolution; although most people would probably consider it to be de-volution. Larger brain/greater intelligence/stuff like that no longer confers a consistent survivorship or procreative advantage; on the contrary. So, I'd say we're definitely evolving but in the direction of what I personally judge to be less desirable characteristics, both physical and social, rather than more desirable ones. But it's all just the value judgment of anyone's individual personal context.
2. Probably both things are going on; maybe in different proportion in different species.
3. Intelligence is initially going to be an advantage in just about any evolving ecosystem, so without any doubt whatsoever, given the huge number of likely life-supporting planets, there's something we'd label as intelligent life out there. The real question is, do we think it exists on Earth? Depends on how you define it.

Jingy

climber

Somewhere out there

Jan 1, 2013 - 02:08pm PT

Let's try this one at a time:

1. Are humans still evolving? I mean significantly. Are we going to continue evolving bigger brains for instance. Since natural selection requires some sort of environmental pressure, typically involving either a significant culling or isolation of a population, is this likely in a world of 7 billion where people move (and procreate) freely across the planet?

Yes, we don't have a choice in the matter. Given an unlimited amount of time in the future, the only thing that will stop human race is the human race itself. Calling something progress when it poisons the wells will ultimately end everything.

2. Is group selection, as advocated most notably by the evolutionary biologist E.O. Wilson, a viable process for explaining things like altruism or can this be explained entirely by selection at the organism or gene level?

Not sure of the correlation,group selection vs. altruism vs. individual/gene. Too much question for me.

3. What is the likelihood that the emergence of life on a planet will lead to intelligent life given 100s of millions or billions of years of evolution to work with.

This, I think, depends on what is considered "intelligence". Looking back on recent history (within 100 years) we can ask were they really intelligent? With all that has been discovered by some human beings in the last 100 years can we say that anyone from 100 years ago held anything that we can point at as intelligence? I say no, and for this reason I say our growth, understanding, and knowledge will continue to climb as long as those who refuse to think don't stop the learning by society. But, given the last 100 years of progress with regard to knowledge about the world we live in, those who would stifle knowledge and learning, will not be able to stop the dissemination of future knowledge yet to be found, no matter how hard they try.

eeyonkee

Trad climber

Golden, CO

Topic Author's Reply - Jan 1, 2013 - 02:22pm PT

Clearly, topic 1 would seem to have a "correct" answer, and I got it wrong. What really interests me about that one is whether we are continuing to evolve to be smarter, bigger-brained hominids. Seems that many people just assume that this is true as if there is something inevitable about it. My take has always been you need selection pressure for that to happen, and the current conditions just don't support that. I think it's going to be technology-aided processes that will accomplish this in the future.

With respect to 2, this is a little more estoric than the other two, and required reading would be something like The Selfish Gene by Richard Dawkins and The Social Conquest of Earth by E.O. Wilson. The consensus, I believe, is that group selection just doesn't work, but it definitely is a controversial subject in the field and really interesting from the standpoint of how morality came about.

Ken M

Mountain climber

Los Angeles, Ca

Jan 1, 2013 - 02:24pm PT

1. Evolution is alive and well in the human species, and operating to full effect.

evidence:

continuing breaking of athletic records--production of exceptional "tip of the iceberg" individuals

continuing lengthening of AVERAGE lifespan--production of better average "stock"

continuing identification of those who in past would have been discarded as misfits or disabled and would have been discarded, but are now seen as genius--Einstein, Hawking, Temple Grandin.

Also of note: you can't pass genetics on, if you die. One of Einstein's kids died of diptheria, a vaccine preventable disease that we almost never see anymore, and another, who was considere SMARTER than his dad, was institutionalized with schizophrenia and basically destroyed by the treatments of the time...which would not happen now. He almost certainly would be able to live a nearly normal life, and utilize his genius, and pass his genes on. (two Einstein grandchildren do live in Los Angeles, one is a doctor)

zBrown

Ice climber

chingadero de chula vista

Jan 1, 2013 - 02:30pm PT

here's more on the possible emergence of life ...

this discovery is profound in that one of the worlds, a "super-Earth" designated Tau Ceti "e" -- may be sitting inside the star's so-called habitable zone.

http://www.supertopo.com/climbing/thread.php?topic_id=2031364&msg=2031364#msg2031364

Ken M

Mountain climber

Los Angeles, Ca

Jan 1, 2013 - 02:35pm PT

I take issue with the concept of "smarter, bigger brained"

I don't neccessarily think one needs a bigger brain to be a smarter human.

I actually know Hawking, and he doesn't have a remarkably large head!

I think this might be something far more subtle than that.

jstan

climber

Jan 1, 2013 - 02:40pm PT

Excellent idea for a thread.

1. Are humans still evolving?

Come back in 100,000 years for the answer. We, of course, imagine that evolution will result in larger brains, because that is what we would like to think. The brain already consumes a reported 20% of our energy budget. If we get another ice age the gains from brain size will have to be quite large to compete with the increased demand on energy budget due to climate. I am of course assuming reality TV will be only a minor blip and will soon cease to exist.

A video I recently posted of Michio Kaku has a fairly specific comment on this topic.
http://www.youtube.com/watch?v=NK0Y9j_CGgM

2. Is group selection, as advocated…

If you have not seen it, I would recommend Ramachandran’s TED talk on mirror neurons. He has data on these neurons and suggests the brain is proactively hard wired to promote the ability of homo sapiens to work in concert. And it has bearing on altruism. The data supporting this purported ability of humans to cooperate is, unfortunately, becoming quite spotty of late.

http://www.youtube.com/watch?v=QZw3lxyuhEU

The new branch of science known as Evolutionary Psychology seems very interesting as it carries the field away from the extensive anecdotal studies popularized by Freud and moves in new directions. Below is an extended discussion between Prof. Buss and Richard Dawkins.

http://www.youtube.com/watch?v=t0pwKzTRG5E

3. What is the likelihood that the emergence of life on a planet will lead to intelligent life given 100s of millions or billions of years of evolution to work with.

Lawrence Krauss has considered the energy limitation on information in the universe and feels life itself must needs cease to exist. No form of life will have billions of years in which to pursue anything. Sorry to bring this up on a climbing site but hey. You got to tell it like it is. There will be no 5. 10^20.

http://www.youtube.com/watch?v=8Cnj8MIQ0HY

Now that I have gotten this off my chest I need to go read Ed’s links.

Edit:
As regards brain size and "intelligence", a wonderfully ill-defined term, look up Ramachandran's talk on how the regions of the brain are interconnected specifically to facilitate metaphorical thinking.

Reilly

Mountain climber

The Other Monrovia- CA

Jan 1, 2013 - 02:49pm PT

Any dispassionate perusal of human evolution must conclude that the primary
survival strategy is the ability to sign welfare checks and have 8 children.