Forgot your password?
typodupeerror
Science

Study: Dinosaurs "Shrank" Regularly To Become Birds 138

Posted by samzenpus
from the getting-small dept.
An anonymous reader writes A new study suggests that large dinosaurs shrunk to small birds to survive over a period of around 50 million years. Aside from a few large species, most modern birds are predominantly tiny and look nothing at all like their prehistoric meat-eating ancestors. The evolutionary process that governed this transformation has not been well understood, but now researchers from the University of Adelaide in Australia have put together a detailed family tree mapping the evolution of therapod dinosaurs to the agile flying birds we see today. Their results indicated that meat-eating dinosaurs underwent several distinct periods of miniaturization over the last 50 million years which took them down from an average weight of 163kg to just 0.8kg before finally becoming modern birds.
This discussion has been archived. No new comments can be posted.

Study: Dinosaurs "Shrank" Regularly To Become Birds

Comments Filter:
  • Smile (Score:5, Funny)

    by nospam007 (722110) * on Sunday August 03, 2014 @02:18PM (#47594933)

    Think of it as evolution in action.

    • No no no. (Score:2, Funny)

      by Anonymous Coward

      First of all, Dinasours never existed. The fossils were put there by Satan.

      Now, since birds are claimed to be dinasours one can only come to the conclusion that birds do not in fact exist.

      The data is there to prove it. The only point where you and I disagree is how that data is interpreted and since I have the Word of the Lord, it is obvious that I am right.

      • by linearZ (710002)

        First of all, Dinasours never existed. The fossils were put there by Satan.

        Wrong. The fossils were put there by a noodley appendage.

        • by ArcadeMan (2766669) on Sunday August 03, 2014 @04:16PM (#47595401)

          Wrong. The noodley appendage is a make-believe idea put in our heads by the Invisible Pink Unicorn to test our faith in her.

        • Re:No no no. (Score:5, Insightful)

          by mark-t (151149) <markt@l y n x . b c .ca> on Sunday August 03, 2014 @09:35PM (#47596497) Journal

          Please.

          Pastafarianism is readily historically verifiable as being deliberately conceived of as a fake religion for the express purpose of satirizing other religious beliefs, not so much to mock those specific beliefs, but to actually show how ludicrous it is to use science classes in school to teach scientifically unverifiable stories about the origin of mankind, arguing that the Flying Spaghetti Monster story has exactly as much scientifically credible as any other unverifiable account of the origin of mankind (which is a mostly accurate assessment, the only difference that I can think of being that how the story of the FSM came about, and the entire purpose of its existence, to mock the teaching of Intelligent Design in schools, is very well historically documented, so the comparison isn't valid 100%... but it's close).

          So if you are going to lay claim to any kind of sincere belief in a religion, you should probably try picking one whose origins are lost in obscurity by the passage of time, or at least pick one where there isn't an abundance of documentation to show that the originator only invented it to mock a specific idea, not as something that anyone should necessarily seriously believe in.

          • Re:No no no. (Score:4, Insightful)

            by Boronx (228853) <evonreis@3.14159 ... ing.com minus pi> on Monday August 04, 2014 @12:16AM (#47597187) Homepage Journal

            Please. That origin story was put there by Satan to test our faith. You don't really believe it was all made up, do you?

            • by geekoid (135745)

              It's was put there by God to test are faith in Satan. All Hail the lord of Knowledge, Satan.

          • by gmhowell (26755)

            How do you feel about the Latter Day Saints?

            • Wait... that isn't a parody religion too?
              • How do you feel about the Latter Day Saints?

                Wait... that isn't a parody religion too?

                The Latter Day Saints Movement was never meant as a parody religion. Joseph Smith Jr truly believed what he preached. He saw inconsistencies among the various Christian sects of the day and the King James Translation of the Bible. What Joseph taught was supposed to remedy that; it was never meant to be taken as a work of fiction, or used to parody the mainstream. Whether he taught eternal truth is a matter of faith. I believe, you probably don't. Let's live and let live.

                As another poster pointed out, the Fl

          • by linearZ (710002)

            Pastafarianism is readily historically verifiable as being deliberately conceived of as a fake religion for the express purpose of satirizing other religious beliefs,

            All that readily "historically verifiable" evidence, just like these fossils, was staged.

    • by RoLi (141856)

      Wait, I've been told that evolution "stopped" 10,000 years ago and that is why human intelligence is exactly the same for everybody except for dissidents who are stupid, stupid, stupid.

      I'd really be interested what kind of supernatural force made evolution "stop" for humans but allowed it for dinosaurs and all other non-humans. Also why - and how - does this supernatural force make an exception to the exception for dissidents and makes only them stupid, while everybody else is exactly equal?

      Basically we hav

    • Re:Smile (Score:4, Funny)

      by StripedCow (776465) on Monday August 04, 2014 @07:18AM (#47598617)

      Actually, because of the expansion of space-time, the dinosaurs stayed the same size.

  • Makes Perfect Sense (Score:5, Interesting)

    by rmdingler (1955220) on Sunday August 03, 2014 @02:23PM (#47594953)
    In times of extraordinary resources, an ecosystem's offspring are afforded the opportunity to grow larger, and larger is often a breeding advantage.

    In times of constriction of resources, those life forms with the minimal caloric needs tend to flourish.

    What a beautiful and strange World it must have been in the dinosaurs heyday to support a seven ton carnivore and a 50,000 to 100,000 kilo plant eater.

    • by russotto (537200)

      What a beautiful and strange World it must have been in the dinosaurs heyday to support a seven ton carnivore and a 50,000 to 100,000 kilo plant eater.

      Support global warming!

      • by pijokela (462279)

        There was a lot more oxygen in the air back then. It wasn't just hotter. With the lower oxygen levels the huge dinos wouldn't do so well because they didn't have muscles for breathing like we do.

        • Re: (Score:3, Informative)

          by Arker (91948)

          "There was a lot more oxygen in the air back then. It wasn't just hotter. With the lower oxygen levels the huge dinos wouldn't do so well because they didn't have muscles for breathing like we do."

          I think you are rather badly mistaken [wolframalpha.com]. There was actually much less oxygen in the atmosphere then.

          Warning, link is not really a webpage, js required :( but you can search yourself for a better source.

          • Don't be mistaken by the name of Michael Crichton books. Those big dinosaurs were Cretaceous.

            Your point still stands that there wasn't more oxygen in the atmosphere, but by the end it was about the same [wolframalpha.com]
          • That's a neat graph. I think there might have been little oxygen because they overgrazed the vegetation, and there wasn't enough green to keep up with it, so the equilibrium point was at a lower o2 level, lower vegetation abundance, and those dinos that could drag it out long on very little food, or minimum food, but able to graze anything that sprouts, proliferated. This requires cold blood like snakes that can go for a whole year without feeding. (Humans can only do it for a few weeks on fat reserves befo
          • by dryeo (100693)

            Wonder what the atmospheric pressure was at the time? We always assume that the atmosphere has been consistent but I've never seen any research on it.

        • They better have muscles for breathing. There were no cpap machines.
      • Ah, but there were no modern humans in the Jurassic.
    • by tomhath (637240)
      Growing larger is a response to competition, prey grows larger to defend themselves from predators. Predators grow larger in order to hunt successfully. Dinosaurs were in an arms race against each other.
    • by Kjella (173770)

      If you were watching it you'd probably feel you were in slow-mo. Ever tried to ride an elephant? It's sloooooooow and even though they might stampede over a very short distance it's quickly over and back to a trot. Despite the huge size most estimates of T. Rex's speed suggests a human sprinter could outrun it, it only needed to catch even slower dinosaurs. If you want action I'd take a leopard and a gazelle instead.

      • by Anonymous Coward

        Have you ever seen elephants running? Walking and running are different.

    • larger is often a breeding advantage.

      We got a chubby chaser over here.

    • HG Wells in the Short History Of the World, says, that right before they went extinct, dinosaurs highly proliferated in extremely great variety, but then ice-age hit. Only a few species made it through the ice age, and 37C temperature mammalian wombs or even hotter, 42C but externally heated bird eggs, that hugged and nurtured their offspring in warm fur or feather arms once born, had an upper hand in fighting against cold, compared to plain lizards that just left their eggs behind. In fact he says ice-ages
    • Exactly. Scarcity of resources selects for smaller organisms. Including little sheepish things we call mammals.
  • by flyneye (84093) on Sunday August 03, 2014 @02:57PM (#47595101) Homepage

    I wanna see the armor plated Tyrannopenguin.

  • The Red Queen (Score:5, Interesting)

    by NoNonAlphaCharsHere (2201864) on Sunday August 03, 2014 @03:07PM (#47595145)
    I'm sorry, birds are the showiest class on the planet. Any theory about how they went from ~160Kg to ~1Kg in (only) 50 million years needs to have a healthy dose of sexual arms race to be plausible.
  • by Anonymous Coward on Sunday August 03, 2014 @03:20PM (#47595207)

    Because of the square cube law, gigantism is energetically expensive. The bigger an animal gets, the heavier it gets (disproportionately), and the more energy it needs to move. But size is relatively easy to tweak genetically, so making animals bigger to out compete their mating or territorial/predatory rivals must have been a solution which evolution hit on pretty quickly. But then evolution moved on, developing more sophisticated technology like feathers, hollow bones, and more powerful brains which could support flight and cooperative pack hunting, and gigantism became a relatively more expensive and less useful trait. Huge dinosaurs disappeared, for the same reason huge battleships did. Put a t-Rex into a forest with a pride of hungry lions. How long do you think the Rex would last?

    - Tristan

    • by ArcadeMan (2766669) on Sunday August 03, 2014 @04:15PM (#47595395)

      Put a t-Rex into a forest with a pride of hungry lions. How long do you think the Rex would last?

      What do you mean? An African or European tyrannosaurus rex?

    • by khallow (566160)

      Put a t-Rex into a forest with a pride of hungry lions. How long do you think the Rex would last?

      Depends on whether there's something the Rex can eat. It probably could hunt elephants or hippos, but there's not much else out there that they can catch. Most mammals are small and fast. I imagine the Rex would become almost exclusively a well-armed scavenger. And the lions' calculation would be that something that big and that toothy is going to take a bunch of us down if we try to take it on. Let's hunt zebras instead. Odds are good that the Rexes would learn to follow lion prides around and take their k

    • Huge dinosaurs disappeared, for the same reason huge battleships did.

      Wrong. Battleships were so big because they needed to be to carry what was then the most effective weapon available: high-caliber, long-range gunnery. By the end of WWII they had been rendered obsolete by the development of effective naval aviation, carried on aircraft carriers that are even bigger than battleships were.
      • by RoLi (141856)

        Aircraft carriers are only bigger by volume but they weight much less than the biggest battleships. So for all practical purposes (especially cost) they are smaller than battleships.

        • Aircraft carriers are only bigger by volume but they weight much less than the biggest battleships. So for all practical purposes (especially cost) they are smaller than battleships.

          Nope. The biggest carriers are larger than the biggest battleships.

          The Nimitz is near 100,000 Tons.

          The Yamato (largest ever battleship) was closer to 65,000.

          The HMS Vanguard (the last battleship built, and the UK's largest, though given it's radar and armament---100 AA guns---it was as much of an antiaircraft platform as a battl

    • The T-Rex would go extinct after only 50 years if all it had to eat was lions.

      Unless of course someone raised a lot of lions to keep feeding T-Rex's. Or maybe T-Rex might think it was really cute how a kitty was chewing on it's bunions -- that tickles.

    • by RoLi (141856)

      Put a t-Rex into a forest with a pride of hungry lions. How long do you think the Rex would last?

      Interesting question, the answer would obviously depend on whether the T-Rex would find enough food. Maybe the T-Rex could hunt elephants? Also new research hints that T-Rex may have been more of a scavanger than a hunter, so maybe T-Rex just follows the lions and chases them away everytime they kill a gazelle? On the other hand, a T-Rex probably weights more than a pack of lions, therefore it would have to snat

  • Bad phrasing (Score:4, Insightful)

    by twistedcubic (577194) on Sunday August 03, 2014 @03:47PM (#47595289)
    This is evolution. The dinosaurs did not "shrink". The smaller dinosaurs within a species had a higher survival rate.
    • by martas (1439879)
      The phrasing is good enough for anyone who isn't an idiot or a pedant, while also being concise. I.e. what a headline should be.
      • Haven't you encountered a frightening number of ID idiots who insist - often a top volume - my grandaddy warn't no MONKEY!
        Your observation is true, but given the sheer number of people proud to be ignorant, not super useful.
        For their benefit - and thus, ours - we gotta watch that flippant phrasing.
        As the environment changed, dinosaurs evolve to be smaller, and eventually into birds.
        Not catchy, but easier to defend.

        • by geekoid (135745)

          And you know whats really cool? There is now evidence that all dinosaurs may have had at least downy feathers when hatched.

          So, next time you have the opportunity to hold a baby chick. close your eyes, imagine no phones, cars, planes, no humans. Just dinosaurs. The feeling you get when petting that chick is the same thing you would feel holding a dinosaur.

      • The phrasing is good enough for anyone who isn't an idiot or a pedant

        I.e., not good enough for Slashdot.

    • Survival rate of smaller dinosaurs is only the 'selection' part of evolution. Another other important part of evolution is mutation, so I think it IS fair to say they shrank. Imperfection + Inheritance + Selection + Mutation = Evolution
    • by m.shenhav (948505)
      First of all, the phrasing can very well refer to cladel trends (this is how I would interpret it in a technical text), in which case it kinda makes sense (while being admittadly somewhat ambiguous) to speak of Dinosaurs shrinking. Second of all, I resent the implicit conflation of evolution with natural selection espoused by your last sentence. Yes, this is evolution. No, this does not automatically mean every phenomenon is explained by selection (despite what adaptationists try to sell you).
  • Sorry guys, we got lost on the way.

    Signed,
    turtles.

  • "...and look nothing at all like their prehistoric meat-eating ancestors." Have chickens. Check out their feet. "Dinosaur" will indeed cross your mind.
    • by tomhath (637240)
      And watch a chicken when it catches a mouse. Vicious carnivore will cross your mind.
      • by jpellino (202698)
        IF ONLY they went after other rodents - they've cleared my lot of bugs, but they couldn't care less that there are voles about.
        • by RockDoctor (15477)

          they couldn't care less that there are voles about.

          If you want a bird that will eat voles, get a bird that has evolved to eat voles. Try either a falcon (kestrel, hobby, or other variants of "raptor"), or an ostrich. In either case, expect it to put "chicken" on it's menu too.

          Big things eat little things ; the size difference between chicken and vole isn't enough in favour of the chicken for the vole to be considered "food" (unless it's a baby?). Few insects are that big though, so they're on "Chicken Men

      • by the gnat (153162)

        Wow, yeah. There are some good videos [youtube.com] on YouTube - it's not hard to imagine similar scenes in the Triassic.

        • by RoLi (141856)

          Oh come on - the mouse in the video seems to be extremely slow and probably already heavily injured. The chickens outnumber the mouse and are so confused and timid that they let it get away.

          • by Jesrad (716567)

            That's domestication for you... You can be pretty sure that guinea fowls, which have kept more of their hunting instinct, would have made short work of the mouse.

            That said, from the point of view of the mouse that whole scene must have played much like something out of Jurassic Park 2 or 3.

    • by the gnat (153162)

      Have chickens. Check out their feet. "Dinosaur" will indeed cross your mind.

      We have wild turkeys where I work. Every time I see a flock, I think of the little pack of dinosaurs (Compsognathus?) that eats Wayne Knight in "Jurassic Park", and shudder. And the turkeys are actually much larger than this. Fortunately they also seem to be relatively slow-moving and don't eat anything larger than insects.

    • Some birds have heads that practically scream "dinosaur".

  • How is it a tech site can't produce a decent news reader? Come on, this stuff was solved in the 90's or so. I write up a nice posting, I see that all the lines between paragraphs are missing. Let's see, should I manually go and add a "br" between each? Ok, easy enough, but my entire living has been about making computers to the simple boring stuff for me. So I innocently click "options", make the correct selection, and "save". Well, it saved alright. Everything except the posting I had just spent 15 minutes

    • by rubycodez (864176)

      haven't you heard, all the slashdot intelligentsia made a mass exodus to kuro5hin.org

      • by sysrammer (446839)

        Thx, I checked it out, saw this immediately "Jerry Jeff Walker 'LET OUR MIKE GO'". An interesting poem, I thought, then finally got it that it was to the tune of Mr. Bojangles. I may have found a new home.

  • Should I post the same post here that I did on SovlentNews? Oops, too late, I didn't.

    But it had something to do with tasting like chicken. It was really good, seriously.

  • by Chas (5144) on Sunday August 03, 2014 @06:13PM (#47595911) Homepage Journal

    *ROAR!*

    T-Rex: "See! THAT'S how you do it! Make sure they can't run because they've just packed those "pants" things with a fear-spawned self-crapping! Now you try!"

    *CHEEP!*

    Hummingbird: "How'd I do? He still looks terrified. But I can't tell if that's me or you!"

    T-Rex: *SNIGGER* "Oh! It's you!" *SNERK* "Definitely you!"

  • by stoborrobots (577882) on Sunday August 03, 2014 @09:53PM (#47596547)

    http://xkcd.com/1211/ [xkcd.com] This is a good world....

  • by Anonymous Coward

    I can't believe that 'scientists' actually believe their 'facts'. 50 million years - 50 trillion years - not gonna convert from 163kg lizard to just 0.8kg bird. Birds become birds, lizards become lizards ,,,,,

If God had a beard, he'd be a UNIX programmer.

Working...