"Mankind Has Stopped Evolving."

[onager]

:wow:

Who said that? Some old-earth Creationist?

No...it was the current media go-to guy on science-y questions, the photogenic physicist Michio Kaku.

(Since it's the weekend, I'm catching up on my Pharyngula reading.)

I often enjoy seeing Kaku on TV, but even I've flinched a couple of times when he treated the Roswell Fundamentalists very gently.

A comment on the thread seems to identify the problem: I quite liked one of Kaku's earlier books on string theory, but I had the dubious pleasure of attending one of his talks in Birmingham about 7 years ago.

We were a gang of physicists and I remember getting absolutely infuriated with how vague and waffly he was, even within his own field. He is extremely specialised in a particular branch of theoretical physics, and seems to have no knowledge outside that field.

Very smart people who wander out of their field always remind me of the Nobel Prize co-winner (for the transistor) William Shockley. Late in life, Shockley decided he was an expert in genetics and went way off the deep end, right into a murky pool of openly racist idiocy.

http://scienceblogs.com/pharyngula/2011/02/why_do_physicists_think_they_a.php

[EvolveOrConvolve]

1. Kaku isn't stupid

He's just got a bad case of know-it-all-ism. I enjoy some of his television shows, but in many of them I think he's blowing smoke because he likes 1) sounding smart; and 2) saying fantastical things that get a reaction.

[Orrex]

2. Linus Pauling is another Nobel wanderer

And the darling of the "vitamin C cures everything" cult.


Whatever his past achievements, Kaku seems to have decided that his current paycheck makes him a tv personality first and a scientist second.

[dmallind]

3. No way to tell, but it is possibly true.

Not of course that the biological process has stopped, but that it is unlikely to be causing any changes in the human population as a whole, because there is no survival or breeding advantage among human allotypes.

Devoid of all the greek-derived terms, that's all evolution in the vernacular sense of species changing over time is. Giraffes got longer necks because the ones who could reach higher food survived food scarcity better and could pass on their long-necked genes. Stick insects who blended in better did not get eaten and could pass on their stick-like traits, and so on. Humans of course got their big brains and opposable thumbs because only the ones who used tools and smarts could survive to pass on their genes - being otherwise a pretty weak, slow and defenseless species compared to competitors and predators of early hominids.

But humanity has for much of its H. sapiens history and even moreso today than ever become largely immune from the factors that allow one allotype to survive over others. We have no large-scale predators beyond bacteria and viruses (and artificial means to fight off most of them). We shape and manage our environment for protection against the elements. We can eat almost any available food type including ones not naturally provided. We breed year round and not in a way restricted to those with the most strength or brains or height or any other criterion. In what way would any mutation create a survival or breeding advantage over those lacking it?

The only factor likely to substantially differentiate the human population into survive/die groups is immunity to some as yet unknown virulent disease. But even then immunity variation is mostly random among populations. It would have to be a pretty specific disease that gave, say, very tall people a survival advantage. Yes the surviving population would be blessed with X antibodies and yes that is technically evolution in action (again - if he was referring to genetic mutation per se he's a moron, but in common layman's usage evolution is normally used to mean speciation) but not the kind of "macroevolution" (yes I know - airquotes for a reason) that the term conjures up in a mass audience.

Nothing will stop mutation. But what mutation is likely to change the human population as a whole? Even if we imagine some immunity to all cancers for example, humans right now almost always get to breeding age before dying of cancer. Where is the genetic advantage for the immune?

[laconicsax]

4. Lactose tolerance, adaptation to a low-oxygen environment, etc.

Evolution is still taking place. Just because the results aren't always outwardly visible doesn't mean it isn't happening.

http://www.nytimes.com/2010/07/20/science/20adapt.html?pagewanted=all

[semillama]

5. Indeed. In fact, we're seeing what happens when selective pressures change

i.e., genes that may not have been passed on due to maladaptive pressures in the natural environment now have a greater chance to contribute to the genome. It's far too early to say if there's any slowing of evolution in our species. Lots of nasty things could happen that would give it a good kick in the pants.

[laconicsax]

6. I dislike that expression

"slowing of evolution"

It implies that there's a 'normal' rate, which isn't true.

[dmallind]

14. Pretty sure I said that. Note the "vernacular usage" bit.

Since we have artificial means to cope with lactose intolerance, and since oxygen level adaptation can even adjust in a single specimen (ask anyone who has moved into the mountains a few years ago how much more difficulty they had breathing at first compared to now) how is the population with these adaptations going to gain a survival or breeding advantage. Even all but the looniest creationists accept cell mutation (the technical meaning of evolution) but not speciation by natural selection (the vernacular usage). I certainly accept both by the way, but barring some massive cataclysm, the ability of humans to overcome biological and environmental risks WITHOUT mutation X conferring a genetic advantage over mutation Y means there is little mechanism for speciation to occur.

[laconicsax]

15. Evolution doesn't need a cataclysm to work.

Though artificial means allow for people lacking beneficial mutations and those with some deleterious mutations to survive, it doesn't mean that those mutations won't spread through the population. A gene doesn't need to confer a breeding mutation to propagate itself, it just needs to not get in the way of reproduction.

Lactose tolerance and adaptation to oxygen levels are just examples of beneficial mutations that have been identified. Sickle-cell trait is another good one. Every time an individual reproduces, there are between 100-200 mutations in the resulting offspring. Those mutations are typically neutral, and it's usually only when they build up and act in concert with each other to create a novel phenotype that they're ever really noticed.

Since there are thousands of mutations spreading through the population and there's no way to predict the end results, making predictions about selective advantage is a bit short-sighted.

[Warpy]

16. Given cutting edge genome research that suggests that

retroviruses have been a mechanism for big evolutionary jumps in the past, I suspect the next step in our evolution might be a devolution to a shorter average lifespan thanks to the HIV virus. Instead of the aging process we now see that just causes us to wear out sometime after our threescore and ten, we're likely to see aging as a gradual petering out of the immune system.

Unless we find a vaccine and make it universal. Which is unlikely.

[toddaa]

7. Kaku is an enthusiastic String Theory populizer

He makes his money popularizing the wierder aspects of String Theory, which isn't much of a theory at this point. Kaku is the entertainmnt wing of science. Nothing wrong with that. Richard Dawkins, Carl Sagan, and Neal DeGrasse Tyson are great populizers of science, but Kaku has a knack of finding himself in woo circles. Too bad, because he's really media savvy and very good at explaining hard science in popular media.

[laconicsax]

9. I will hereafter only refer to String Theory advocates as "experimental theologians."

[toddaa]

10. Experimental?

That would be a good starting point for them.

[laconicsax]

11. There've been experiments...

...and the results weren't exactly in line with the theological predictions.

Here's one: http://io9.com/#!5714210/string-theory-fails-first-major-experimental-test">String theory fails first major experimental test.

They also like to claim that the only way to invalidate experimental theology is to disprove quantum mechanics. In line with that, http://www.popsci.com/science/article/2010-09/researchers-figure-out-how-test-untestable-theory-everything">this is one way they propose to validate their mathematical masturbation.

[Dr. Strange]

8. Devo said it first, didn't they?

[TZ]

12. The view that humans aren't evolving actually isn't real woo

In college I read up on the debate..the point isn't so much that man has stopped evolving..its that he no longer is strongly influenced by the environment so that evolutionary pressures aren't as strong as they used to be, that cultural forces are a stronger force at this point. On this I don't really disagree. Evolution is strictly driven by the need to adapt to a changing environment. Well, mankind is pretty much the only organism that now controls the environment instead of vice versa. And of course we compensate for genetic traits that would normally be selected out for in the natural environment, so in a sense we are guiding our own evolution now.
So while of course we are still evolving, its a different rate and in a different direction and its strongly influenced by our own culture almost more than by our environment.

[PVnRT]

13. That was the sense I got as well

The selection pressures have changed, although the environment is catching up to us now.

[astral]

17. If you're not paddling upstream, you're floating downstream.

So we may be DE-volving now, as we can't stay still and not change. SOME people will be evolving but a huge number of us will be devolving as the elements of nature that have pushed us forward are no longer there to affect us in our man-made environment. Our man-made environment is what will now shape the man of the future.

We will keep getting DIFFERENT, not necessarily BETTER.