The People Who Saw Evolution

April 28, 2014 4:49 PM

"Peter and Rosemary Grant are members of a very small scientific tribe: people who have seen evolution happen right before their eyes."
posted by brundlefly (35 comments total)

Bookmarked for later, because The Beak of the Finch was an amazing read.
posted by showbiz_liz at 4:56 PM on April 28, 2014 [3 favorites]

Mad props to the Grants, but anyone who has needed an updated flu vaccine has experienced the effects of evolution happening in real time. Medical doctors see evolution happen before their eyes all the time. Unfortunately, this is often referred to in the popular media as bacteria/infectious agents "developing" resistance. In the vast majority of those cases you can replace "evolution" (cross generational change>), for "development". (Within generational change).
posted by cnanderson at 5:12 PM on April 28, 2014 [10 favorites]

The whole article is great but if you want to skip to the evolution part, try page 3. I'm a little confused about why this is evolution of species and not just simple breeding for traits.

I'm 20 years rusty on this but flu is sort of weird because the DNA has special hypervariable regions for the protein coating, right? The virus evolved for rapid evolvability in this one specific way. It's still natural selection, just an atypical genetic path.
posted by Nelson at 5:20 PM on April 28, 2014 [1 favorite]

Great article and Beak of the Finch was indeed amazing. The finches don't "evolve" in the layperson's sense (with that implication of progress). They adapt. Beaks get longer, then shorter, then longer again in response to changing environmental conditions.

We all sort of know that's how evolution works, but the Grants' research drives the point home.
posted by mono blanco at 5:21 PM on April 28, 2014

Mrs 'cicletta read much of this piece to me aloud while I made the morning cuppa, equally charmed by the science and the devotion.
posted by billcicletta at 5:22 PM on April 28, 2014

I'm a little confused about why this is evolution of species and not just simple breeding for traits.

"Breeding for traits" is evolution. Anytime the frequency of a trait in a population changes, evolution is occurring. In this case, natural selection caused a change in the frequency of different beak sizes.
posted by hydropsyche at 5:31 PM on April 28, 2014 [8 favorites]

Couldn't you argue that an Ames test is seeing evolution happen right before your eyes?

And yes, breeding is absolutely evolution. I'd argue that directed evolution is a major tool in molecular biology - we just usually call it a screen. Maybe I'm over-reaching there?
posted by maryr at 5:39 PM on April 28, 2014 [2 favorites]

They met at the University of British Columbia in Vancouver in 1960, where Rosemary was lecturing in embryology, cytology, and genetics, and Peter — still a graduate student in zoology — was her teaching assistant.

This is such a reversal of the professor-student cliche that I immediately love this couple.
posted by maryr at 5:48 PM on April 28, 2014 [4 favorites]

The seasonal flu vaccine may not be the best example of evolution here, as noted above (but I understand why you mentioned pathogens, cnanderson). Speaking very generally, a lot of what happens with flu is more of a geographical mixing of known viral strains. FDA just had its public meeting on next year's vaccine antigen selection at the end of February, and the recommendation repeats that of last season (e.g. there's been no evolving lately relative to which flu viruses are most likely to get up your snout). Changing polyvalent flu vaccine profiles are more of a global health policy risk assessment thing than an expression of viral evolution.

Now start talking to me about vaccine and antibiotic failure generally and we've got much more room to agree on the relative importance of evolution to virulence, pathogenicity, and so on.
posted by late afternoon dreaming hotel at 5:51 PM on April 28, 2014

I'm with maryr - anyone who's cloned or subcloned has not only seen evolution, they've engineered it.
posted by gingerest at 6:09 PM on April 28, 2014 [2 favorites]

Gene flow is an evolutionary mechanism. Evolution happens at the population level, so the shifting seasonal flu vaccine is still a good example of evolution as long as populations are changing in their relative frequencies of traits. Novelty can happen (I.e. Spread of a new mutation), but is not strictly required. Shifts in the relative frequencies of existing traits can sufficiently be termed "evolution".
posted by cnanderson at 6:12 PM on April 28, 2014 [2 favorites]

Fantastic read. A lovely couple. Made me jealous of their childlren's upbringing.
posted by greenhornet at 6:13 PM on April 28, 2014 [1 favorite]

Beak of the finch that pecked you.
Yeah, I got nothing.
posted by Joakim Ziegler at 7:34 PM on April 28, 2014

"Breeding for traits" is evolution. Anytime the frequency of a trait in a population changes, evolution is occurring. In this case, natural selection caused a change in the frequency of different beak sizes.

Exactly. And, to further delineate "those members of a very small scientific tribe: people who have seen evolution happen right before their eyes", in addition to Peter and Rosemary Grant, that very small group includes:
Dog Show Competitors
Race Horse Owners
Master gardeners at every seed company in the world
Breeders of exotic animal and plant variants
Sociologists studying genetically-isolated groups such as Appalachians
and so on.

Why, that very small scientific group couldn't possibly number more than a million people.
posted by IAmBroom at 7:38 PM on April 28, 2014 [2 favorites]

Again, The Beak of the Finch is delightful. I'm glad that it, and the article, make the explicit point that evolution is not linear. A linear view of history (I'm sure there's a name for the theory), one of constant progress, is a personal pet peeve. I understand that it's comforting to have a narrative, but the evidence available says that life on Earth and history in general is full of chaotic chance, and grants us infinite complexity.

This is also why I have a hard time believing in God, or at least (to rip off Spinoza) a God who's interested in human affairs. I think that for some, it helps to think of life as a story in which human beings are the prime actor, that it gives them importance and purpose on this planet. I don't want to knock that, because a sense of belonging and value is central to good health, but for me the opposite is true: I find comfort in the (apparent) chaos of the cosmos. It's freeing to be part of something so intricately constructed that I can't possibly tear it all down.

This is all to say I hope the Grants' field work continues forever, if only to show us that we aren't as significant as we think we are.
posted by Turkey Glue at 7:48 PM on April 28, 2014 [2 favorites]

What's really striking to me is that at least two of the Grants' doctoral students (featured in The Beak of the Finch) have gone on to become major contributors to the modern study of evolution. Trevor Price and Dolph Schluter are both incredibly well-renown in study systems and evolutionary questions completely different than the finch work.

Price has done extraordinary work on speciation in birds (I am especially fond of his ring species work on warblers in the Tibetian plateau). Schluter has his own "phylogenetic tree" of academic descendents who are top-notch stickleback researchers (stickleback are fish that, among other things, repeatedly evolve into benthic and limnetic forms when invading freshwater lakes. Schluter is also a really, really, nice guy and the outgoing president of the American Society of Naturalists).
posted by cnanderson at 8:14 PM on April 28, 2014 [1 favorite]

"Breeding for traits" is evolution.

I'm going to disagree with that, although hopefully it's more than a boring quibble about word definitions. To me the amazing part of Darwin's theory isn't that traits are inherited; humans had been breeding livestock for millennia and understood that. It's that natural selection along with inheritence is enough to explain the origin of species, the fantastic variance of life on Earth. It was an enormous conceptual leap, as important as Galileo.

I was confused by the article about the Grants' work because what they were describing felt more like the minutiae of breeding individuals than the grand march of evolution across whole species. But then the selection they are observing is natural, not artificially chosen, so it meets the criteria of evolution and I was just wrong.
posted by Nelson at 8:31 PM on April 28, 2014 [2 favorites]

Selective breeding is not the same as adaptation/ natural selection.
posted by fshgrl at 9:26 PM on April 28, 2014

Selective breeding is not the same as adaptation/ natural selection.

The selective pressure is a different source (selective breeding is more efficient), but the mechanics of inheritance and mutation are identical.
posted by lkc at 11:18 PM on April 28, 2014 [3 favorites]

"Peter and Rosemary Grant are members of a very small scientific tribe: people who have seen evolution happen right before their eyes."

This is only true if you exclude the vast majority of life on Earth along with the subset of biologists who've done the vast majority of genuinely useful work in actually understanding the mechanics and mathematics of evolution, providing a foundation in physics and chemistry for the whispy theoretical work that preceded it.

Microbial Evolution is a central yet oddly neglected field where evolutionary biologists tend to not understand microbiology well enough to do anything meaningful with it and microbiologists seem to mostly only play with it as an afterthought - but there is still so much amazing and fascinating work still being done with it. at the bottom of my profile is a pretty paired down collection of Blasdelb's favorite papers in microbial evolution, with the free access ones marked with *** so as not to tease you. They have also been selected to present different aspects of the field, and while some knowledgable observers might claim a phage bias, I think that is totally defensible. As always if you would like copies of those papers that are not publicly available - for the purpose of this academic discussion that we are having - feel free to memail me with an email address I can send PDFs you want to.
posted by Blasdelb at 11:50 PM on April 28, 2014 [5 favorites]

Evolution covers anything that alters the genetic makeup of a population. Weeding your garden is evolution in action, as is breeding pigs, brewing beer, using triclosan soap, or planting monoculture crops.
posted by benzenedream at 1:20 AM on April 29, 2014 [1 favorite]

The power of words is in their ability to differentiate and identify, not in our ability to pack as many things as possible into a single utterance. Maybe arguing about how broadly we can define "Evolution" isn't a very productive line of thought? When a word means everything, it means nothing at all.
posted by I-Write-Essays at 4:52 AM on April 29, 2014

Oh, the beauty of microbial evolution, Blasdelb! Richard Lenski is one of my favorites, too. He writes wonderful blog summaries on his work
posted by cnanderson at 5:00 AM on April 29, 2014 [1 favorite]

> "Selective breeding is not the same as adaptation/ natural selection."

This can only be true if you believe that humans are supernatural entities.
posted by kyrademon at 5:26 AM on April 29, 2014 [1 favorite]

> humans are supernatural entities.

If we define Nature as "Everything that isn't the result of Human Will," as we do when we use the term "natural selection," then we're fine. It's the assumption that the opposite of Natural is Supernatural that gets you into trouble. A more appropriate antonym is Artificial, meaning, "the result of human artifice."

There is no point in making the distinction that the selection is Natural if the opposite of natural is "It doesn't exist." Then all we have is Selection.
posted by I-Write-Essays at 5:31 AM on April 29, 2014 [1 favorite]

Selection is, in fact, all we have. The natural vs. artificial distinction is a relatively meaningless one in this case, really.
posted by kyrademon at 5:57 AM on April 29, 2014 [3 favorites]

I disagree that it is a meaningless distinction. Artificial selection is dirt common, whereas natural selection is relatively more rare (though "very small scientific tribe" is an overstatement). Perhaps the laws of physics don't care about human intention (or lack there-of), but humans do. Observing how things behave when humans don't interfere is interesting.
posted by I-Write-Essays at 6:16 AM on April 29, 2014

Artificial selection (i.e. animal breeding and plant husbandry) are indeed dirt common. I would argue that natural selection is in fact infinitely more common. It may only seem rarer because so few humans care to sit still long enough to document it properly.
posted by BigLankyBastard at 7:45 AM on April 29, 2014 [2 favorites]

Huh, I always thought that gene mutation is a necessary part of evolution and is necessary for a new species to evolve.

I mean, a population has a certain distribution of genetic features, let's say finches with 80% long beaks and 20% short beaks. Environmental changes can make short beaks advantageous, so that over time there is a shift to 30% long beaks and 70% short beaks, or whatever. Not a single mutation is necessary for this, and it's still the same species. This process is comparatively fast and can be observed over a few generations, by the Grants or race finch breeders or whoever. It is also reversible, as long as the gene pool is large enough and the DNA manifested by those features is not lost.

On the other hand, there is the mechanism of mutations, i.e. random changes in the DNA, say, through (natural) radiation or whatever. Only a small percentage of those random changes will be viable and advantageous. Many, many cumulative mutations may eventually lead to a new species. This takes thousands of years and could not have been observed by the Grants.

I'm not at all sure about the nomenclature here, but if the quick process manifesting itself after a few generations is also referred to as "evolution" then what do you call the slow process involving mutations if you want to distinguish it from the quick process?

Furthermore, I'd be hesitant to call the quick process "evolution", because I can already hear the argument from evolution deniers: "If evolution really happens so fast, then why are there no spontaneously evolved dinosaurs roaming the earth?"
posted by sour cream at 8:17 AM on April 29, 2014

Some folks in this thread are conflating "speciation" (the evolution of reproductive isolation) with "evolution" (change in heritable traits over generations). Indeed, these are separate topics (and speciation does not have to be slow!). The wikipedia articles are pretty good on these topics. Another well written text for the general public is "Why Evolution is True" by Jerry Coyne for those that want to know more.

Evolution via natural selection that drives random mutations to complete fixation does not need to take "thousands of years", if your population size is big enough and the selection gradients strong enough. Here, take 3.5 minutes and watch bacterial evolution for yourself. The time lapse video summarizes more than 3.5 minutes in duration, but on the order of hours, not years.

This video depicts is what sour cream has referred above to as the "slow process".
posted by cnanderson at 11:57 AM on April 29, 2014 [4 favorites]

So, and please excuse my stupidity, but are dogs examples of evolution (controlled breeding), i.e. from wolves we now have chihuahuas and Grea Danes? (I hope this isn't a really dumb question.)
posted by shoesietart at 1:21 PM on April 29, 2014

Not a dumb question at all. If you take the literal meaning of evolution, ie "change" you can argue that they are.

However the scientific field of evolutionary biology is primarily concerned with change in the natural world that leads to speciation (which dog breeding has not) and to better adapted creatures (not pugs) so no, it's not really what people in the field mean when they say "evolution", which is generally a shortcut for something else. If this sounds ill-defined and confusing, IT HELLA IS. People write papers that are some variation on "guys, I think we should define this term better" pretty regularly. Every other essay you write I'm college as an evolutionary biologist is some variation on the theme as professors attempt to beat conflicting definitions into your head.

And that's without pop culture and laypeople using the word in a different, but perfectly ok, way. And biologists in other fields who have only a vague notion of the current state of evolutionary biology theory. Or maybe a very good notion but they still use the word they way they want to. Etc etc
posted by fshgrl at 2:02 PM on April 29, 2014

Oh my goodness, the picture in that Lenski blog gives me shudders. PUT THE LIDS ON YOUR DAMN PLATES, THAT IS HOW YOU GET contaminANTS.
posted by maryr at 2:40 PM on April 29, 2014 [2 favorites]

whereas natural selection is relatively more rare

No it's not. Natural selection is acting on every species on earth all the time. A lot of the selection pressure is either actively selecting for, or at least not selecting against, things staying the same but it's still there.
posted by shelleycat at 2:49 PM on April 29, 2014 [2 favorites]

The Continuing Evolution of Genes
posted by homunculus at 6:15 PM on April 30, 2014