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Are there any other bipeds on Earth besides humans?

  1. Nov 30, 2004 #1
    Are there any other bipeds on Earth besides humans? I am not talking about animals such as chimps that walk partially on two legs or animals that do it occassionally. I am talking about an animal that spends its whole life walking on two limbs and qualifies as a true biped. Thanks
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  3. Nov 30, 2004 #2


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    Birds spring to mind.
  4. Nov 30, 2004 #3


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    Ratites such as ostriches and emus in paritcular are on the same scale as humans, but all birds meet the qualification since their other pair of limbs evolved into wings.

    There were also many bipedal dinosaurs.
  5. Dec 1, 2004 #4
    Kangaroos and wallabies are. Kangaroo rats are almost completely bipedal.
  6. Dec 1, 2004 #5
    Kangaroos are somewhat problematic, because when not in motion, they often use their tail as a third point of contact. In that sense, they are not strictly bipedal..
  7. Dec 2, 2004 #6
    Is your question in relation to convergent evolution??? Or are you just curious???

  8. Dec 2, 2004 #7

    I am just curious. i never thought of birds as bipeds and I don't know idf science does classify them as so. They are good examples of animals that do use two limbs when traveling on the ground. Thanks
  9. Dec 2, 2004 #8
    Yeah, and humans lean against walls or rocks. Or sit in a chair or recline on a bed when at rest. If they can and do stand without using their tail then I say they're bipeds. If they rest using their tail as a prop that's a different matter.
    I'm at a loss to think of any other bipeds really. There is that monkey that hops along sideways on two legs. Hey, what about gibbons? They use only their arms when swinging through the branches. Basilisk lizards run bipedally on water.
    Last edited: Dec 2, 2004
  10. Dec 2, 2004 #9
    Well ostriches and emus never fly so they count no matter what.
  11. Dec 3, 2004 #10
    Good point.. Being bipedal is rather difficult. It takes a lot of energy to maintain an upright position, and maintain balance. Much easier to lean against something, or even sit down. Anyway, there's a difference. See below.
    That's the point. Although I may be mistaken, AFAIK, they almost never use only their hind legs, except when running (the tail is more usefull for steering and balance than propulsion...). Dogs can walk on their hind legs too for short periods, but they are clearly not bipedal.
    Last edited: Dec 3, 2004
  12. Dec 3, 2004 #11
    I wonder how they should be classified then? Tripedal? I was under the impression that "pedal" referred to how many legs they use to move along on the ground or on or in water.
  13. Dec 4, 2004 #12
    That's a good question. Technically, the tail is not a leg, so I guess you could call them bipedal. But if I'm correct in saying they use their tail almost like a third leg, then "bipedal" would not be totally accurate.. Then again, it would depend on how you define "bipedal".

    I think a little googling could help resolve this issue...
  14. Dec 4, 2004 #13


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    if it exists

    !BIGFOOT :devil:
  15. Dec 6, 2004 #14


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    I think that's a type of lemur that does that. There was a good documentary hosted by John Cleese about it...and of course, he majestically demonstrates the hop as only he can.
  16. Dec 7, 2004 #15
    Would a penguin count?
  17. Dec 7, 2004 #16
    They're birds, walk upright on land and use their flipper wings to "fly" underwater. I'd call them bipeds, or semi bipeds.
  18. Dec 8, 2004 #17


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    Only with the proper schooling.
  19. Dec 9, 2004 #18


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    An uneducated penguin could count.
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