Birds: Evolution and Innovation in a Changing World

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In this talk Prof. Edwards will celebrate the remarkable 100 million year history of birds and describe the imprint of ancient innovations, such as feathers and flights, on many aspects of avian biology, right down to their DNA. He will then describe how diverse environmental challenges, such as climate change, disease, toxic metals and urban noise, test the resilience of birds today.


Written By: Harvard University Science Lectures
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  1. This is a really good lecture. Birds are a lot more different from mammals that I thought, and have a number of advantages to our design. He said that birds have a unidirectional breathing system. I don’t see how that could be. Does not the air enter and exit via the beak? What pushes the air around?

    • In reply to #1 by Roedy:

      This is a really good lecture. Birds are a lot more different from mammals that I thought, and have a number of advantages to our design. He said that birds have a unidirectional breathing system. I don’t see how that could be. Does not the air enter and exit via the beak? What pushes the air arou…

      I never really appreciated how cool birds were. Then I dated a “birder” and of course at that point I said “going hiking and looking at birds? oh yeah that sounds awesome!” (and of course really thinking “how long do I have to do this until we have sex?”) But the amazing thing is I soon got almost as hooked on watching the birds as she was. They really are kind of amazing and beautiful. My favorites, and you can’t get much different are the little humming birds and the not so little hawks and falcons. I saw a raptor, think it was a falcon this was in a park in a big city, take a pigeon in mid flight once and it was one of the coolest things I’ve ever seen. Not so cool for the pigeon of course but they are the only bird I wish there were less of.

    • In reply to #1 by Roedy:

      This is a really good lecture. Birds are a lot more different from mammals that I thought, and have a number of advantages to our design. He said that birds have a unidirectional breathing system. I don’t see how that could be. Does not the air enter and exit via the beak? What pushes the air around?

      Birds have air sacs in their body that expand as they breathe. The trachea is bidirectional as usual, but the air flows in and out of the air sacs such that the passage of air through the lungs themselves is one-way and constant no matter if the bird is inhaling or exhaling. There are diagrams here

      • In reply to #5 by Callinectes:

        In reply to #1 by Roedy:

        http://www.youtube.com/watch?v=iigxJXFJF4U

        This video shows an animation of avian air flow. It does not show various glottises that I assume must open and close at various points. It is completely different from the mammalian scheme. I feel very impressed at the ingenuity. The scheme does not look completely “finished”. The brilliant part is all air flowing over the diffusion surface is fresh from outside.

  2. Adorable kingfisher photo.

    urban noise

    Distressing as this is, I’ve noticed it occurring in rural areas, too. Noisy trucks drive parallel to a fragile pond system; yesterday I watched a crop duster fly over corn fields – wondered what Rachael Carson would think (there are trees interspersed) given the conditions of Earth since ‘Silent Spring’ was written 50 years ago.

  3. Professor Scott Edwards. One of the interviewed scientists in my lower division general college biology text book.

    Just come out with a book? No longer low key, I assume.

    A long story is the evolution of birds and through this coming warming of the globe another chapter will be added to the story. Not so for all species.

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