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The Dolphin With Leftover Legs

Posted by ryuzaki0 on from the pass-me-the-speech-center-of-the-brain dept.

ectotherm writes "Japanese scientists have captured a dolphin with vestigial legs. Evidence, it would seem, of a land-dwelling past and observable evolution." From the article: "Fishermen captured the four-finned dolphin alive off the coast of Wakayama prefecture (state) in western Japan on Oct. 28, and alerted the nearby Taiji Whaling Museum, according to museum director Katsuki Hayashi. Fossil remains show dolphins and whales were four-footed land animals about 50 million years ago and share the same common ancestor as hippos and deer. Scientists believe they later transitioned to an aquatic lifestyle and their hind limbs disappeared. Whale and dolphin fetuses also show signs of hind protrusions but these generally disappear before birth."

26 of 441 comments (clear)

  1. I urge you to be insightful by suv4x4 · · Score: 2, Insightful

    On this article. You can't. You can be funny or informative. Let the challenge begin NOW...

    1. Re:I urge you to be insightful by misanthrope101 · · Score: 2, Informative

      If natural selection were purely random, there would be no speciation. I've read several books by Dawkins, and Darwin's Origin of Species and randomness, though present, is not the driving factor. There is a random variation in the gene pool of any population, but the selection process, which favors or disfavors certain traits, is far from random, and drives change in the population by predisposing individuals with certain characteristics to be more likely to leave offspring than their competitors. Yes, the randomness is a component, in that if there were no variation there would be no foothold for the selection process, and thus no evolution. But randomness with no selection does not drive speciation, just as variation with no selection would also fail to drive it.

    2. Re:I urge you to be insightful by Alsee · · Score: 2, Informative

      But then you have dolfin A and human B but no in-between combinations (dolfin with stubbly legs)

      The first and most important point is that the "dolphin with stubbly legs" *did* exist. We have the transitional fossils.

      If you look back 10 or 15 million years, dolphins merge with whales. If you look back... if I recall correctly... about 50 million years, you find fossils of proto-whales with stubby legs. We have tons and tons of transitional fossils... such as whales with stubby legs... all over the entire fossil record.

      Now, why doen't this particular in-between form still exist? Well thing about it. With stubby legs, it wouldn't be able to walk on land very well. And with stubby legs, it wouldn't be able to swim as well either. Dolphins are perfectly streamlined super fast swimmers. Having legs hanging off the sides would just be a drag in the water. They wouldn't be able to swim as fast to catch prey, and they would have to work harder and get more tired faster with the extra drag.

      The "in-between" can simply die out. In some cases the "in-between" gets wiped out exactly because both "opposite ends" totally out-compete it.

      Having wings and light bones makes you a great flier. Having four legs and strong bones makes you great on the ground. The two in-betweens aren't so good. Having 4 legs and light bones makes you fragile and vulnerable - regular ground animals have you totally beat. Having wings and heavy bones makes you a lousy flier that can't go very far or very fast and you get tired real fast - regular birds have you totally beat.

      But notice that in both the dolphin example and the bird example while the in-between is "bad", it can still be better than one end if the other end does not exist. An "in-between" animal with wings and heavy bones may be a crappy flier, but it is still a better animal if if is the ONLY animal that can fly. If there are no good fliers around to out-compete you, then being a crappy flier is great. After you start flying, then you make other changes (light lighter bones) one step at a time to become more and more specialized to flight, and each improement out-competes and wipes out the previos "in-between" that was less specialized to flight. And the same goes with the initial development of dolphins. Being an "in-between" poor swimming mammal poorly adapated to living in the water is an advantage if there's lots of food available living in the water and it keeps you safe from non-swimming land predators and there's no good swimmer mammals to compete with you. And then over time the better swimmers (and ultimately the legless swimmers) out-compete and wipe out the "in-between" lousy swimmers.

      When you branch off in a new direction, the leaders in that direction will often beat out and wipe out the less specialized "in-betweens", an on going competition to run and specialize in a single direction. An on going series of modifications to better specialize for life in the water or a life of flight or whatnot.

      Of course not all kinds of "in-between" get actively eliminated like that. Sometimes you start with the "in-between" form, and then you simply have the population divided in two for some reason, and the two halves of the population simply drift apart over time. At some point they get so far apart that they simply cannot interbreed anymore, and then teher's no longer any way to create an "in-between" that has one new trait that first appeared in population and another new trait that first appeared in the other population.

      One of the simplest and most common causes of this is when a species population gets split on two different land masses or split on opposite sides of a river or split by a mountain range or split on opposite sides of a desert ot anything else. I think you'll agree that humans living in different places drifted apart. The Japanese are different than the Irish are different than Eskimos are different than South Africans are different than Native Americans. You'll notice that those differen

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  2. Not vestigial... by kooky45 · · Score: 2, Funny

    The dolphins are growing new limbs they'll need to construct their spaceships to get off the earth.

  3. Self defense really. by kooky45 · · Score: 5, Funny

    The dolphins need hind legs to roundhouse the sharks with frickin' lasers on their heads.

  4. Dolphins coming ashore... by Hamster+Lover · · Score: 2, Funny

    Fishermen captured the four-finned dolphin alive off the coast of Wakayama prefecture (state) in western Japan on Oct. 28, and alerted the nearby Taiji Whaling Museum, according to museum director Katsuki Hayashi.

    Anyone considered that dolphins are growing hind limbs so they can go ashore to capture a few Japanese to take back to their Hominid Museum?

  5. Far cry from legs by eclectro · · Score: 5, Insightful

    I read the article, and those aren't legs, they're fins.

    I will only believe that a dolphin has legs when it walks up to me and shakes my hand.

    --
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  6. And then... by Aqua+OS+X · · Score: 2, Insightful

    ... the Japanese killed the rare ocean dwelling animal in order to sell four flipper dolphin medicine and magical flipper medallions to the rich.

    --
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  7. Another thing about Taiji, Japan by Wills · · Score: 5, Informative

    Taiji, Japan, is the site of the annual ritual dolphin massacre in which fishermen drive pods of dolphins into shallow coves and stab them with spears. You should see it. It is quite a sight. The sea water turns red with blood, and the air is filled with the extraordinary sounds of screaming dolphins (they literally seem to scream).

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    1. Re:Another thing about Taiji, Japan by AndyboyH · · Score: 2

      Not picking on your comment - more just adding additional weight to it:
      don't forget that some plants react too when attacked - releasing chemicals into the ground to warn other plants and/or increasing the toxicity of their sap.

      That's why I'm amused that you say 'vegan or hypocrite' - vegans are hypocrites too. It's just they conveniently forget that most nutritious food that they can eat is/was living at some point...

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    2. Re:Another thing about Taiji, Japan by Hogwash+McFly · · Score: 2, Insightful

      The key difference is that us Westerners kill cows for food and other products and we at least try to pretend we're humane about it with our stun-bolts and such. I'd rather the food I eat be borne out of as little pain and suffering as possible. Our methods may not be perfect but at least there's some reasonable purpose behind slaughtering cows and pigs. We don't mindlessly spear them in fields as part of some outdated display of self-doubted masculinity. To compare the two for purposes of apology is asinine.

      I don't believe dolphins are magical animals. If you want to eat dolphin, fine, just try to sustain the population and do it humanely. But if you want to butcher thousands of them just to show how dominant you are or because 'granddaddy did it' then you need to get the fuck over yourselves and start acting like you're in the 21st century.

      Why is it that when a small child mindlessly tortures animals we say that it is a disturbing indicator of sociopathic behaviour, yet when a group of grown adults do it we are supposed to celebrate their culture?

      It's fucking bullshit.

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    3. Re:Another thing about Taiji, Japan by Hogwash+McFly · · Score: 3, Insightful

      Why can't I do both? Why can't I criticise the repugnant aspects of my own culture as well criticising the repugnant aspects of others?

      Oh I see, it isn't about giving criticism where it's due, it's about dodging it. Yeah, funny that.

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    4. Re:Another thing about Taiji, Japan by ettlz · · Score: 2, Informative

      How do you know the grandparent poster was white, and what the hell does it have to do with the point raised?!

    5. Re:Another thing about Taiji, Japan by Jeremi · · Score: 2, Interesting
      Plants at least demonstrate reactions - the original post that I made pointed out - they are aware and respond to attackers, and can warn other plants via hormones. Milk does not possess these abilities.


      Milk isn't the issue -- cows are. It's a simple question of whether the production of each item causes suffering in sentient beings. Again, the concensus opinion is that plants are not sentient. Argue otherwise if you want, but it only makes you look silly. Drinking milk, on the other hand, is thought to cause suffering to cows, who are believed to be sentient. Hence, vegans don't drink milk. If you can create milk without using animals, vegans are happy to drink it (e.g. soy milk, rice milk)


      If vegans truly and honestly cared for living creatures, they'd commit suicide before they inflicted any more damage to the planet's ecology. But then, because they do not, they
      are inherently valuing their lives over a multitude of other living things. Which defeats their own argument that they are protecting life and preventing suffering. They're just redistributing it to something that isn't so cute and fluffy, that can't stare them back in the eyes. That is my argument.


      Again, you are deliberately misrepresenting the Vegan position so that you can cut down a straw man. Vegans' goal is not to protect all living things, but rather to not cause suffering in sentient beings. Vegans (like most people who aren't trying to construct a spurious argument) believe that plants are non-sentient and therefore okay to eat.


      There is no contradiction between not wanting to cause suffering in other sentient creatures, and in valuing your own life. Indeed, committing suicide would not be consistent with the vegan position, because committing suicide would cause suffering in sentient creatures (specifically, the people who care about you).


      Your argument is unfounded. I suspect you are merely trying to demagogue vegans because you feel threatened by them. If you were to consider their arguments seriously, you would then be forced to critically examine your own life choices, and that scares you.


      -Jeremy (not a vegan, but not afraid to consider their line of reasoning)

      --


      I don't care if it's 90,000 hectares. That lake was not my doing.
  8. should the vestigial limbs be removed.... by jemptymethod · · Score: 5, Funny

    that would be de-feeting the porpoise

  9. Close shot of the four legged dolphin by suv4x4 · · Score: 2, Funny

    Close shot of the four legged dolphin can be seen here.

  10. The Land Sharks have been doing it for years by HighOrbit · · Score: 2, Funny

    [visitor] Knock Knock...
    [you] Who's there?
    [visitor] Pizza Delivery
    [you] I didn't order any pizza.
    [visitor] umm....Avon
    [you--while opening the door]. I didn't order any....AHHHAAGG

  11. Re:You are the FIRST STUPID person i saw on slashd by Hogwash+McFly · · Score: 2, Insightful

    That's ludicrously quixotic.

    To imply that someone is a hypocrite because they are against mindlessly killing intelligent beings capable of feeling pain and suffering but would also wash their hands of harmful bacteria based on the platform that 'all life is sacred' is ridiculous.

    While I agree that too much stock is put in 'cute' animals by anti-cruelty organisations, the absolutist 'kill all or nothing' stance you propose is illogical, unhelpful and only serves to distract from the real acts of barbarism, such as the one discussed here.

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  12. Re:Catholics believe in evolution, fossil record, by mrand · · Score: 2, Informative
    How is the world do fossils prove evolution? Where are the intermediate forms? What?! What do you mean there aren't any?

    Of course there are - you just choose to put your head in the sand to ignore them. In fact, they are being discovered all the time... here's one just last week:
    http://www.sciencedaily.com/upi/index.php?feed=Sci ence&article=UPI-1-20061102-12453000-bc-us-missing link.xml

    Read on, if you dare to actually learn something:
    http://www.skepticwiki.org/wiki/index.php/Intermed iate_Forms/
    http://en.wikipedia.org/wiki/List_of_transitional_ fossils/

    Then stop saying the fossil record "proves" evolution because it doesn't. It proves there were dinosaurs. It doesn't prove evolution at all.

    Actually, it doesn't even prove there were dinosaurs. All we know is that we find bones in the ground. The evidence indicates that there were dinosaurs. "Proof" in science is a misnomer.
    http://www.newton.dep.anl.gov/newton/askasci/1993/ biology/bio039.htm/

    It's really about evidence:
    http://www.space.com/searchforlife/seti_devore_the ory_050303.html/

    Note that I carefully avoided talk.origin's to keep you from claiming that that everyone refers you to the same source. The vast majority of the scientific community is in agreement about the vast majority of the conclusions drawn from the vast evidence that has been discovered thus far: evolution is a fact.
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  13. Re:You are the FIRST STUPID person i saw on slashd by Dunbal · · Score: 2, Funny

    and why the world is STILL suffering from new 'flu' types coming out of china due to the abhorrent amount of germs and viruses your genocide with those bi-weapons caused to breed there over time.

          As a physician I'd just like to say one thing:

          Huh?

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  14. Why must everything have legs? by icepick72 · · Score: 2, Insightful

    a bottlenose dolphin captured last month has an extra set of fins that could be the remains of back legs

    Or the extra set of fins could simply mean dolphins had an extra set of fins! What idiot has to turn everything into legs? Next they'll find a rock with protrusions and there will be the proof that rocks once walked the earth.

  15. Re:You are the FIRST STUPID person i saw on slashd by Jack9 · · Score: 3, Informative

    It's important to note that holding something sacred does not mean you do not kill and eat it. Native Americans held the buffalo sacred AND thought they were tasty.

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  16. Re:You are the FIRST STUPID person i saw on slashd by Hogwash+McFly · · Score: 2, Insightful

    Yeah, I respect this notion at the end of my second paragraph here, but you still get my point if you substitute 'all life is sacred' with 'you shouldn't kill anything' in the original post.

    It goes without saying that hunting an animal for food and treating it was reverence and respect is far removed from butchering loads of dolphins just for the hell of it.

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  17. How about a whale with legs? by Bowling+Moses · · Score: 2, Interesting

    Amid a bunch of other stuff, talkorigins has a nice photgraph of bones from the hindleg of a humpback whale, specifically a femur, tibia, tarsus, and metatarsal. This dolphin's rear fins will be similarly composed, and not at all like fish fins in skeletal structure. It'll be pretty cool to see how it compares to other known cetacean rear legs from both modern examples and the fossil record once they X-ray the fins.

  18. Fins = Legs by SydShamino · · Score: 2, Interesting

    I think you need to read the aptly-timed November 2006 National Geographic article "A Fin Is a Limb Is a Wing: How Evolution Fashioned Its Masterworks". It describes how the same genes (Hox genes, if I skimmed the article correctly) shared among many otherwise very differennt creatures produce species-specific results. For example, the same genes create fins in a fish, wings in a chicken, and limbs in a human (insert graphic, page 115), or control the length (or lack of) neck in a mouse, goose, or python (insert graphic, page 121).

    At least for a limited time, the article is even on the web for you to read:
    http://www7.nationalgeographic.com/ngm/0611/featur e4/

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  19. Re:You are the FIRST STUPID person i saw on slashd by daiichi · · Score: 2, Interesting
    Secondly, apparently because you are stupid, or you are disfunctional to the teeth, you have chosen to disregard the iq factor of either squids, or dolphins.

    Hmmmm. I had to think about that. If the dolphins are so smart, then how come they allow themselves to get herded into a cove and slaughtered for the last hundred years? I mean, it would be different if we were talking about human prey who are limited by the same constraints that human hunters would be; but really dolphin can travel much faster than most boats, can dive deeper than most fishermen can, and have a far greater range not constrained by the contents of a fuel tank. So if they're so smart, then how come the Japanese have been able to slaughter them for so long?

    I mean, think about it... if all they did was communicate to each other and say "hey, stay out of the Sea of Japan in Q4 of any year" that article would be about how Japanese fishermen are scratching their heads and having to import dolphins from Mexico in order to slaughter them...