Has human evolution stopped?
online.wsj.com
online.wsj.com
I loaded HN, saw a headline which mentioned "evolution", saw that this headline was sourced from the Wall Street Journal, and thought to myself "Damn, the Journal really is turning into yet another right-wing rag...I wonder what they've dredged up this time"
...then I did something that, apparently, most of the members leaving comments thus far did not do: I read the article.
First, this is a book review. The only question of accuracy is how well the review represented the content of the book. Second, though the term is not used in the article, the mention of Gould gives away the topic of the book. It's a concept called "punctuated equilibrium", and it's very much an open question in biological research.
The most troubling result of the ID movement is the subsequent balkanization of views on all sides of the issue. What we have here (and by here, I mean this comment thread, not the article) is a prime example of individuals jumping to "defend" evolution without giving much thought or analysis to what it is they're defending.
Modern theories of Evolution are as complete and sound as Newton's laws of motion... I should know, since I'm currently completing a Ph.D. looking into some of them...
Every time an egg gets fertilized that's evolution in progress, every time a human being does not get offspring because his/her desired mate gets snagged by a more appealing specimen that's evolution in progress and every time somebody gets killed by accident before they get to reproduce that's evolution in progress too.
The fact that the changes accumulate too slow for you to witness this in real-time does not mean it does not happen.
Any scientist that works in biology claiming that human evolution has stopped will soon find himself/herself the laughingstock of his profession.
I like "descent with modification" when explaining what evolution is to layman. They find it easier to understand as the term isn't so loaded.
What, then, would devolution be?
http://www.google.com/search?q=%22higher+animals%22
The Encyclopedia Britannica mentions plants that are more highly evolved than others: http://www.google.com/search?q=%22highly+evolved+plants%22
http://www.britannica.com/EBchecked/topic/463192/plant
for example, the most highly evolved plants reproduce by means of seeds, and, in the most advanced of all plants (angiosperms), a reproductive organ called a flower is formed.
http://en.wikipedia.org/wiki/Devolution_(biological_fallacy)
Unless you mean something entirely different than what most people mean when they say "devolution", what you are referring to is just evolution. The same way that "reverse racism" is just racism.
I suggest you read the wikipedia link
I read it before you gave the link. The discussion page conflicts with the current state of the main page. http://en.wikipedia.org/wiki/Talk:Devolution_(biological_fal...
evolution can be both 'progressive' and 'regressive'. [...] if a population deteriorates genetically it certainly is something like 'devolution', and this article completely ignores this issue. [...] deterioration, misconceptions aside, is a real thing, and we need to stop giving people the impression that it is only a 'fallacy'.
I said "Devolution is a nonsense concept" because, as I stated before, what is referred to by "devolution" is just evolution. The term, as used commonly, implies some sort of objective heirarchy to evolution, and although organisms may get labeled with terms describing their complexity, that does not mean that one has somehow "devolved" if it evolves into an organism with less complexity. It has just evolved.
Edit:
There's not much disagreeance on the page. There are people talking about using the term to describe something that actually happens, but they aren't talking about what most people mean when they say "devolution".
Dictionaries do not define devolution as just evolution. They define it as retrogade evolution. http://www.google.com/search?q=devolution+%22retrograde+evol...
Yes. Such an objective hierarchy of species is frequently referred-to in Charles Darwin's, The Descent of Man. http://www.gutenberg.org/dirs/etext00/dscmn10.txt
Von Baer has defined advancement or progress in the organic scale better than any one else, as resting on the amount of differentiation and specialisation of the several parts of a being [...] In accordance with this view it seems, if we turn to geological evidence, that organisation on the whole has advanced throughout the world by slow and interrupted steps. In the great kingdom of the Vertebrata it has culminated in man.[...]
Thus we have given to man a pedigree of prodigious length, but not, it may be said, of noble quality. The world, it has often been remarked, appears as if it had long been preparing for the advent of man [...] The most humble organism is something much higher than the inorganic dust under our feet; and no one with an unbiassed mind can study any living creature, however humble, without being struck with enthusiasm at its marvellous structure and properties. [...]
no animal voluntarily imitates an action performed by man, until in the ascending scale we come to monkeys [...]
this is the first case known to me in the ascending scale of the animal kingdom [...]
It is generally admitted, that the higher animals possess memory, attention, association, and even some imagination and reason. If these powers, which differ much in different animals, are capable of improvement, there seems no great improbability in more complex faculties, such as the higher forms of abstraction, and self-consciousness, etc., having been evolved through the development and combination of the simpler ones. It has been urged against the views here maintained that it is impossible to say at what point in the ascending scale animals become capable of abstraction, etc.; [...]
He who believes in the advancement of man from some low organised form, will naturally ask how does this bear on the belief in the immortality of the soul. [...]
I am aware that the conclusions arrived at in this work will be denounced by some as highly irreligious; but he who denounces them is bound to shew why it is more irreligious to explain the origin of man as a distinct species by descent from some lower form [...]
In the lower divisions of the animal kingdom, sexual selection seems to have done nothing: such animals are often affixed for life to the same spot, or have the sexes combined in the same individual, or what is still more important, their perceptive and intellectual faculties are not sufficiently advanced to allow of the feelings of love and jealousy, or of the exertion of choice. When, however, we come to the Arthropoda and Vertebrata, even to the lowest classes in these two great Sub-Kingdoms, sexual selection has effected much. [...]
Man, like every other animal, has no doubt advanced to his present high condition [...] and if he is to advance still higher [...] Otherwise he would sink into indolence [...]
The main conclusion arrived at in this work, namely, that man is descended from some lowly organised form, will, I regret to think, be highly distasteful to many. [...]
Man may be excused for feeling some pride at having risen, though not through his own exertions, to the very summit of the organic scale; and the fact of his having thus risen, instead of having been aboriginally placed there, may give him hope for a still higher destiny in the distant future. [...] with his god-like intellect which has penetrated into the movements and constitution of the solar system--with all these exalted powers--Man still bears in his bodily frame the indelible stamp of his lowly origin.
If you seriously think that we haven't changed our theories of evolution since Darwin, there's not much I can do about that.
I'm not a biologist, but it seems to me that evolution refers to combined mutations over time and not much more, regardless of the perceived "direction" of those mutations. I imagine I would be more frustrated than I am already if I were a biologist.
http://news.ycombinator.com/item?id=482311 http://news.ycombinator.com/item?id=480986
His m.o. is usually to take some weird position and to argue incessantly with all kinds of links to support his position thrown in for good measure.
The interesting thing here is it seems to work, he gets modded up quite frequently and scores tons of karma like this.
Ouch. Succint and harsh.
No, that would be natural selection. The two are different, keep in mind.
like that guy named Darwin found himself, at his own time? :-)
No it doesn't. I call blarney on this article.
http://www.amazon.com/The-Nature-of-Intelligence/dp/B000PY4U...
or
http://www.amazon.com/Nature-Paleolithic-Art-Dale-Guthrie/dp...
or other books I've read on closely related subjects. This is a subject that deserves a lot of books, but one might as well read the better books.
As far as I understand it, evolution is not a thing that stops.
I am significantly annoyed at the propagation of stuff like this. It's like this horrible catch-22 where such a small amount of the population actually understands current theory, and the rest just have these really off-the-wall interpretations, with a similarly small percentage admitting that they have no clue what they're talking about - like how the (stereotypical) average american citizen thinks of abiogenesis, evolution, and the big bang as one big lump of a theory.
Please, correct me if I'm wrong, but saying somethings "evolution has stopped" is nonsense, right?
Evolution only occurs when you've got descent with modification and natural selection working together to push species toward one niche or another. Certainly evolution can stop. Take, for example, dinosaurs!
Of course, extinction is an extreme case. So can an existing species stop evolving? For better or worse, the answer depends on a concept which is still not fully resolved: neutral evolution. The general idea of neutral evolution is that, even when you're not selecting for one variant or another, introducing new variants will make you better fit for the next selection event (presuming you subscribe to the punctuated equilibria views). Essentially, you might not be evolving now (i.e. no selection pressure exists), but you might be stacking the deck to evolve better in the future.
...confusing, right? I love this stuff! :-)
The article's points about evolution continuing in terms of disease prevention, ability to fight germs, etc. are understandable, as with greater population density, exposure to those things do go up.
On the other hand, every time we make a scientific advance which allows people to continue living/reproducing when they wouldn't have before, we lower the selection criteria, and it seems like this would have to slow evolution as a result, right?
And then there is natural selection, which decreases the amount of variation of a species.
It's very important to keep different things separate.
Unless you can give me a strict definition of the boundary between macro and micro, then they're all the same governed by the same laws.