Evolution happens. Even in Oklahoma.

In Tulsa, Oklahoma, over the last 30 years, the number of cliff swallows killed by moving vehicles has drastically decreased. That change can't be accounted for by alterations in traffic patterns or swallow populations, say scientists. Instead, they think it's tied to the fact that the birds' wingspan is also decreasing. This adaptation — whether selected for by vehicular birdicide and/or other factors — helps swallows be more nimble in the air at high speeds, making it easier for them to avoid oncoming traffic. (EDIT: Sorry guys, I made an error here. Some of the researchers were from Tulsa, but study actually happened in Nebraska. Evolution takes place throughout the plains states.)


    1. I’m sure there is somebody who is now going to claim they are making the animals a favor by culling the ones who aren’t fast enough to dodge the boat (or car for land dwelling animal).

  1. I keep thinking “stupid” deer are getting weeded out leaving only the car-dodging super deer.  Nope, not yet.

    1. Human evolution doesn’t seem to be selecting for intelligence either. Maybe intelligence isn’t the evolutionary advantage that we’ve been assuming it is.

      (Of course, maybe it is an advantage, but the advantage is outweighed by something else.)

      1. If you’re smart enough to breed, evolution is pretty much satisfied.  There is no selection pressure for highly nuanced existentialism.

        1.  I wouldn’t be so sure about that. One glance at the personal lives of Camus and Satre would seem to indicate otherwise.

      2. Human evolution doesn’t seem to be selecting for intelligence either. Maybe intelligence isn’t the evolutionary advantage that we’ve been assuming it is.

        Maybe bees and ants used to be individuals, and we’re going to evolve to be a species of workers under one big, bloated leader.

    1. Hey, I’ll give it a shot. Clearly, [fill in deity of choice here] got tired of all the killing and blessed swallows with the physical advantage of shorter wings, making them better at dodging traffic. Creation scientists are currently discussing whether this change occurred within swallow eggs, or whether the wings of already extant swallows spontaneously mutated.

      1. Wow – that’s great.  But you’d think El Gran dios del cielo would consider not getting his / her / its hands dirty with something like DNA.  It constantly mutates – what a pain.  How unpredictable.  A clever and powerful god would simply make the air more dense.  Slower cars, more oxygenated birds with better manoeuvrability.

          1. Hmmm have to run some curves on that – the increase in air resistance would have to be offset by a disproportionate increase in power and grip.

        1. What additional side effects would come with such a change? Would highly oxygenated cars tend to run faster? Slower? Not at all? And as far as DNA constantly mutating, well, that’s just your gran dios del cielo making changes on a whim — it’s not really mutating.

          1. Cars are the Devil’s invention, so were I god I’d happily see them stop.

            You know, you may have me sold on that DNA whim thing.  I wasn’t with it right up till I thought of it as whimsical – then a lot of stuff clicked right into place, just like *that*.  Weird.

    2. They usually counteract in cases like this with the whatever-species-you-are-talking-about is not a new species. I don’t think you can stop having them put their fingers in their ears and going “lalalalalalaaaa… I can’t hear you!!!”.

  2. Oh, come on.  Look, animals learn things.  They’ve learned to avoid the vehicles somewhere down the line and each new generation learns from the last.  Sometimes pro-Evolution folks are looking for anything to validate the theory, but to suggest that the birds have mutated in just 30 years to reduce their wingspan sounds like something a bigfoot enthusiast would say.

    1. And yet the birds have a smaller wingspan than they did 30 years ago; it only takes about 10-12 generations to fix traits when breeding, and the birds have ~2 year generations.

      The selective pressure (cars smashing birds) hasn’t gone away in that time period – if anything it’s grown more intense.

    2. Can’t tell if serious or…?

      The really neat thing about this study is that it highlights just how quickly evolution _can_ happen. It’s not necessarily that new mutations arose for shorter wingspan, but that pre-existing variation in the population allowed selection to act. The mutations can build up slowly over thousands of years, giving you the diversity you need to adapt when the time comes. If you read the recap at Wired linked above, you’ll see that, on average, the birds killed by cars have longer wingspans. The average wingspan of the living birds decreased over time along with apparent roadkill deaths. 

      BAM! Evolution.

      Incidentally, this is why it’s so important to try to maintain large, diverse populations of endangered species: you’re saving all that pre-existing variation for a rainy day. 

    3. Are you going to tell us it’s Intelligent Design?

      Evolution isn’t a theory, it’s a fact.  A substantiated, irrefutable, evidence-based fact.

      A fact that the various shades of churches fight to bury, disquise and ignore in many schoolchild curricula in the USA, giving the gift of ignorance and subservience to the children.

      Which is disgusting, atrocious, repellent and, if any gods existed and I were one, I would re-visit with fury on the perpetrators.

      You’ve got the patter and the veneer of reasonable opposition, but your rhetoric and statement are so full of holes I could hide a flock of swallows in there.

      Christ – what an asshole.

      1. Do you mind if we go back in time so you can replace my high school science teacher who openly mocked and criticized evolution as too improbable to have possibly occurred during Earth’s short (i.e. “a few thousand years”) existence?

        I was one of a handful of students who knew he was full of it, but I’m sure he did quite a bit of damage, especially when it was difficult to convince the majority of my classmates that the teacher was wrong.

    4. Mutation is a slower, more random part of evolution than what is happening here: an alteration in the distribution of genes in a population (i.e. short winged more manoeuvrable birds are becoming more prevalent). If some day a bird with a non-harmful mutation happens to be even better at avoiding cars, its genes will most likely predominate after a few generations, but nobody’s saying that has happened.

      I’m not sure that pro-evolution folks, as you seem to imagine them, even exist. Here’s a clue: if you’re doing science right, you don’t seek to validate a theory; you stand ready at a moment’s notice to invalidate it in whole or in part to get closer to the truth as new evidence comes in.

      It just so happens that we see populations of animals, plants and bacteria adapt over time by changes in the distribution of genes (including new mutations) ALL THE TIME. It’s just not even controversial. So this article isn’t interesting at all from the point of view of debating WHETHER evolution happens (everyone who actually cares about the truth of it knows it does), but is an interesting example of HOW it has happened in one case.

        1. Yep. If you put up a nest camera I’m sure you can see the mommy bird clipping the wings of the baby birds.

          Body modification is all the rage in the bird kingdom atm. Rebellious teen birds leaving the nest color their feathers and have beak rings just to spite the parents, and in college when drunk on fermented fruits they take tattoos of excotic bird songs that essentially says “look at my stupid tattoo”. Never have a tattoo made out of a song you cannot sing yourself!

    5. This is a case of natural selection in action.  The birds aren’t ‘learning’ anything.  Natural selection was well accepted as a mechanism of species change well before Darwin.  (Darwin’s contribution – the theory of evolution – was that natural selection was the *only* mechanism necessary to explain .)

      The birds also haven’t mutated.  A mutation is an alteration in the DNA of an individual.  What is happening is that in every generation, the genes of the parents are combined and half are passed on to the children.

    6. Ahh… well, that didn’t take long. Did you get to three, Mr. Jimson?

      And to Mr. Wyrdmaven… you might want to read up on biology news. There is lots and lots of similar kind of animal populations changing their physical attributes due to changing environments. And no need for any mutation, just natural selection in progress. I would assume even the biggest Evolution denier would know about it (apparently not). I mean… that’s how you get different dog breeds, right?

      What you are _supposed_ to say, as an Evolution denier, is that (you can repeat after me) it is still the same bird species, even though it has shorter wings, it still doesn’t prove Evolution. Ok? Glad to be of service.

      (I’m assuming here he wasn’t joking… my Irony’O’Meter is apparently still broken.)

  3. But humans can’t eat grains because we haven’t had time to evolve from our paleolithic ancestors from hundreds of thousands of years ago.

    1. Lactose persistence is perhaps a better case study, because you can compare populations and all.

        1. Well yes, and I’m amongst those who just don’t do well on eating grains (*). But that doesn’t mean we cannot eat grains. Just go to your local food store and check.

          (*)I cured my IBS by going low carb, and a lot of other health benefits. No, I don’t have celiac disease… at least the docs say I don’t, and I’m pretty sure myself, too, that it’s not the gluten that is the problem. (Tip: If you ever get to do a full length colonoscopy, do it awake and ask to watch the video, that was amazing!) But sure, I can eat grains.

    2. Not the same.
      For something to provide an evolutionary advantage, it has to get you up to or past reproductive age. Birds that get hit by cars don’t make more baby birds.
      Eating grains helped keep people from starving, and, excepting severe celiac and the like, usually doesn’t kill people before their 30s. 
      Whether your metabolism efficiently processes modern wheat is an unrelated story, and most of the health conditions eschewing grains seems to alleviate are chronic, low-level things unrelated to babymaking. YRMV

      1. Well… there is PCO (I know you said “most”) which is related (a long line of “which is related to” later), but that is mostly when you have more than enough nutrition resulting in insuline resistance. But even if it didn’t need that, it still wouldn’t matter as long as eating grains gained more benefits to having your kids staying alive until they reproduce vs. possible disadvantages to reproduction.

    3. We’re not koalas. The energy supplies which we use may not be as physically nutritious âs they once were. Our brains require significantly more energy than other species and so there is some leeway for experimentation in diet despite the physical consequences. From an evolutionary perspective our large brains make a certain degree of flexibility in diet tolerable without further adaptation, mutation.
      We can eat carb rich diets which make us sick almost to the point of physical immobility because we can drive to the supermarket. But without industrialised farming could you have the investment in universities and research which we now have at the other extreme?

  4. I am not an aerodynamic engineer, but I was given to understand that a high wing loading would be bad for maneuverability: http://en.wikipedia.org/wiki/Wing_loading .  The paper states that “Longer wings have lower wing loading and do not allow as vertical a take-off as shorter, more rounded wings”, while artificial aircraft with high wing-loadings require longer takeoff runs to get in the air.

    It may be that because the cliff swallows have smaller wings, their stalling speed is increased, so are now forced to fly at higher speeds. This would put them in the path of cars for a smaller amount of time.  It might also be that while their sustained turning performance is poorer, their instantaneous turning performance is improved.  Because (unlike aircraft) they use their wings to generate thrust, the reduction in the moment of inertia of the wing has positive aerodynamic effects.

  5. One thing for certain: The new phenotype hasn’t made the little fellas any less aggressive- they still dive bomb the unsuspecting pedestrian. BTW, let’s not get too carried away with the “backward anti-science Oklahoma” meme. There are plenty of us science-loving educated folk here; we just don’t make the headlines like the yahoos do. 

  6. By the way, an evolutionary scientist friend of mine (yep) and I had an interesting talk about targeted evolution – i.e. where a species seems to adapt to an environment much more quickly than Darwinian theories accommodate.  It seems the massive reservoirs of DNA that organisms have harbour some sort of memory function – i.e. that a species can re-adapt to something that a historical mutation (that has become redundant/dormant) took care of previously, in response to certain stimuli.

    Things like in times of food scarcity, mice become smaller much faster than you’d expect.

    The whole thing fascinates me.

    I’m still working on evolving into a deity – will let you know how that goes.

    1. “I’m still working on evolving into a deity – will let you know how that goes.”
      That is… brilliant!!! I’ve only aspired to be an Evol Overlord (Work In Progress, still), obviously I’ve been aiming too low!

      Would an Evol Scientist lab help… or how are you approaching the deity evolving process?

      1. I’ve tried all sorts of things.  I can make people pray to me (chinese burns help), but I think it’s prayer by proxy.

        I once tried to help my local church group assist under-privileged kids, but they wanted me to join prayer meetings first, which under-whelmed me (trees falling in the forest etc), and kind of cut off any ecclesiastical route.

        Recently I’ve been working out – got a good program, getting in shape – all deities should have form, say I.  Learned to fly, a bit.  Can surf decently.

        Good diet, love my wife and kids, work hard and honestly, sing, pay my fair whack of taxes … it’s not really coming together though on the deity front.  I’m happier though.

        So yeah – on that Evol Scientist offer … is it a chromosomal thing?

        1. “Good diet, love my wife and kids, work hard and honestly, sing, pay my fair whack of taxes …”
          Yes, yes?!?!? Well… not good diet, but I can make it work!!!

          ” it’s not really coming together though on the deity front.”
          Oh… well that was a let down.

          I don’t have a Evol Scientist lab yet, but I wonder if it would be worth changing my angle from Overlord to Scientist… hmm. They just seem to be able to produce most anything in their labs! But I really wanted that Evol Overlord Secret Headquater, Lab isn’t quite the same thing… but if it would help in achieving the deity status…

          1. Promise to let me know if you make any progress – no matter how small.  I’m pretty keen on being a god.

          2. It’s not that hard.  I can make virtually anyone bow or kiss my hand just by using body language.  And I’m male and in the US.  Next time that someone tries to shake your hand, extend it with the palm down and your wrist relaxed.  Add a big, ugly ring and you’ve taken your first small step toward apotheosis.

    1.  Nah. Real as. I’ve seen ’em before doing their ‘Q&A’ with ‘Evolutionists’. Rather splendidly, the riposte to, ‘So, these ‘transitional fossils’, where ARE they?’ was: ‘Erm, in the British Museum? If you ask, they’ll show them to you’. The crowd did LOL.

  7. The study referred to was not done in Tulsa. It was done in Nebraska. C’mon Maggie, let’s use original sources! http://www.cell.com/current-biology/retrieve/pii/S0960982213001942

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