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Dinosaur Forces Rethink Of Flight's Evolution

Posted by Zonk on from the always-fun-to-think-about-it dept.

gollum123 writes "The BBC reports that a small dinosaur with a long, slender snout and wing-like limbs is forcing a rethink on bird evolution." From the article: "The 90 million-year-old reptile, called Buitreraptor gonzalezorum, belongs to the same sickle-clawed group of dinosaurs as Velociraptor and feathered dinosaurs from China. It may provide tantalising evidence that powered flight evolved twice. One theory suggests the lineage of dinosaurs the new animal belonged to, the dromaeosaurs, originated in the Cretaceous Period (144 to 65 million years ago). But this discovery suggests their lineage can be traced further back in time, to the Jurassic (206 to 144 million years ago), experts say."

3 of 328 comments (clear)

  1. Flight Evolved Twice? by BarryHaworth · · Score: 5, Informative
    From the posting:

    It may provide tantalising evidence that powered flight evolved twice.

    As I recall, powered flight has evolved independantly a number of times.

    Insects

    Birds

    Pterosaurs

    Bats

    and if I not mistaken, fruit bats evolved flight separately to insect-eating "true" bats. That's at least four if not five times.

    --
    I am a Statistician. One false move and you are a Statistic
  2. Re:Insect by rolfwind · · Score: 5, Informative

    I don't know if Hummingbird can be categorized as a different model of flight but:

    http://oregonstate.edu/dept/ncs/newsarch/2005/Jun0 5/hummingbird.htm

    They can hover, fly backwards/forwards, or even upsidedown.

  3. Re:That begs the question .... by drafalski · · Score: 5, Informative
    Actually, it raises the question. Begging the question is a formal logic term that does not mean what most people seem to think.

    Text from the link:
    An argument that improperly assumes as true the very point the speaker is trying to argue for is said in formal logic to "beg the question." Here is an example of a question-begging argument: "This painting is trash because it is obviously worthless." The speaker is simply asserting the worthlessness of the work, not presenting any evidence to demonstrate that this is in fact the case. Since we never use "begs" with this odd meaning ("to improperly take for granted") in any other phrase, many people mistakenly suppose the phrase implies something quite different: that the argument demands that a question about it be asked--raises the question. If you're not comfortable with formal terms of logic, it's best to stay away from this phrase, or risk embarrassing yourself.