Dromaeosaurs on parade

September 17, 2012 • 2:16 pm

From Deviant Art (h/t: Matthew Cobb again), we have this lovely picture of dromaeosaurs, drawn to scale with a dapper human (Fred Astaire?) to the right.

Dromaeosaurs are small bipedal theropod dinosaurs that lived during the Cretaceous.  At least two species may have flown or glided (these include the famous “four-winged” Microraptor gui, #1 and sitting on Fred’s hand), and many were covered with feathers.  They aren’t considered the ancestors of birds, or even in the same group of theropods that gave rise to birds, but are currently regarded as a sister group—closely related to the group that was ancestral to modern birds.

Now the colors are completely speculative, and the feather arrangements best regarded as “informed speculation,” but they probably looked pretty much like this (click to enlarge).  One doesn’t usually think of these “raptors” as cute, but they seem so with colors and fuzz!

Microraptor gui, fossil.  Note the feathers on all four appendages (I’ve added arrows to show them on front- and hindlimbs):

 

And a reconstruction by Ukako Kikutani:

18 thoughts on “Dromaeosaurs on parade

  1. It always amazes me, the extremes that the young earthers go to place dinosaurs and humans together, that they might believe that Fred danced with the dinosaurs.

    It’s a great graphic.

    1. Nova did an interesting show on Microraptor a few years ago where they tried testing out the leg-wings to see how they were likely used.

      The hip structure of Microraptor, as it turned out, prevented it from holding its legs out to the sides like a flying squirrel or cologo, while it lacked a deep keel on the breastbone to support powerful flight muscles in its arms. Instead, after testing it in different poses in a wind-tunnel, they think that it probably jumped out of trees and tucked the legs up next to the tail to increase its surface area and stability for gliding, then brought its legs forward to give it more of a biplane style configuration for landings (as that slowed it and tipped it back- perfect for landing on a tree trunk).

      The video’s probably on YouTube.

  2. I find it amazing how much our understanding of dinosaurs has changed over the last decades. I was a geeky kid in love with dinosaurs no more than 30 years ago, and I still distinctly remember seeing some of those lumbering, tail-dragging, grey-green reconstructions of yesteryore. Yay science!

    1. Yep, I remember seeing my first reconstructions of Deinonychus as a scaly, blood-dripping bipedal iguanid-type thing. Now look at the feathery darling.

      1. Yeah, plus nearly every illustration of a therapod renders the animal with the arms tucked under the body, palms toward the ground, which is not something their wrists were actually capable of, according to many of the current papers I’ve read.

        The best book I’ve read recently was the Princeton Field Guide to Dinosaurs, which contained the most exhaustive collection of data on dinosaur species and anatomy that I’ve ever seen. Of course, it’s already 2 years old.

        Also, I’m reminded of this xkcd.

    2. Any popular dionsaur book over five years old is basically out of date. I got one from 2012 from the library and my 5yo proceeded to critique it. “I don’t think a T. Rex could really attack a Triceratops.” She was willing to concede it might get an old or sick one. She also says the T. Rex in Dinosaurs Love Underpants is definitely an allosaurus instead. Her favourite day out is the Natural History Museum. I thank the dinosaur nuts of Wikipedia, because otherwise there’s no way I’d ever be able to keep up.

  3. “They aren’t considered the ancestors of birds, or even in the same group of theropods that gave rise to birds, but are currently regarded as a sister group—closely related to the group that was ancestral to modern birds.”

    Er… that’s a rather confusing statement. Most modern analyses, including the most recent such as Turner et al. (2012) and Senter et al. (2012), place dromaeosaurids and troodontids in the group Deinonychosauria, which is itself in the group Paraves along with birds. So while dromaeosaurids are not ancestral to birds, and are part of the sister group of birds, they ARE in the same group of theropods that gave rise to birds- Paraves.

  4. From the article
    > Now the colors are completely speculative, and the feather arrangements best regarded as “informed speculation,”

    It’s much more wonderful: many of the colours *are* known and are deducible from multiple independent lines of evidence.

    Feathers preserved in amber in Canada show amazing structural and colouring details: http://www.sciencemag.org/content/333/6049/1619.abstract

    Some of the Chinese fossils are so good that the melanosomes are visible – these structures are highly associated with black coloration: http://www.sciencemag.org/content/327/5971/136

    The melanosomes in some fossils are particular narrow, and this is associated with iridescence. So we know microraptor, for example, was black and iridescent like a modern raven or crow.

    Melanosomes are also visible in fossils from other locations including that haven of evolutionary support, Alabama: http://palaios.sepmonline.org/content/26/6/364.abstract

    Trace metal deposits in the fossils occur where the melanin had been prominent. This allows reconstruction of much colour even if the melanosomes are not preserved: http://www.sciencemag.org/content/333/6049/1622.abstract

  5. One doesn’t usually think of these “raptors” as cute, but they seem so with colors and fuzz!

    “I say; what an adorably cute fuzzy AAAGGHHH! GET IT OFF ME! Aaa…”

    This is why it took another few hundred million years before inter species co-operation based on cuteness and fuzziness could evolve on Earth.

  6. I love dromaeosaurs! I’d like to think that my comment on Microraptor helped spark this post. Even if that’s not the case, I am glad to see such a cool image posted. I hadn’t seen that one before.

  7. It’s clear we have to adopt the dapper gent as the size reference person. As the artist puts it in a comment: “Yeah, those indecent naked waving guys in dinosaur charts have to go.”

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