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Dino kin grew more like birds than reptiles

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Asiliosaurus kongwe, artist’s impression/Andrey Atuchin

From ScienceDaily:

… dinosaurs and their close relatives had much more variation in growth patterns then ever expected, and this variation does not appear to be related to differences between males and females.

Given how little we really know about dinosaurs and their ilk, it’s surprising we expect anything.

Asilisaurus lived during the Triassic Period, roughly 240 million years ago in present-day Africa. With four legs and a long tail, the animal was about the size of a Labrador retriever, and likely maxed at 65 pounds, according to previous studies of the animal. Its exterior skin appearance remains unknown.

Fossils of Asilisaurus kongwe — a combination of Swahili and Greek works meaning “ancient ancestor reptile” — are vital because a large number of specimens were found, largely intact and varying in size and age. Such findings are so rare that paleontologists have struggled with understanding how the first dinosaurs grew, as most species of early dinosaur are known from only a handful of fossils.

Asilisaurus is part of a group of reptiles, the silesaurids, that are close cousins of dinosaurs. Asilisaurus grew similarly to living crocodilians in that both possess differences between individuals in growth patterns.

Yet that growth was much faster in Asilisaurus, closer to the growth rate of birds, rather than living crocodiles. As with dinosaurs, living birds are considered a close living relative of Asilisaurus. More. Paper. (paywall)

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See also: Why weren’t there many dinosaur species?

and

Size helped largest dinos survive longer

3 Replies to “Dino kin grew more like birds than reptiles

  1. 1
    Dionisio says:

    News,
    According to a previous OP I’m a jerk for pointing to irrelevant spelling or grammar errors like the one below:

    The findings are surprising: dinosaurs and their close relatives had much more variation in growth patterns then ever expected,…

    But that’s a printed article, not an email or a text message, hence proofreading is warranted, isn’t it?

    I wonder how many people read that article before it got printed?

    Oh, well. What else is new?

    BTW, why are they so easily surprised? Why did they expect something else?

  2. 2
    Dionisio says:

    The femoral ontogeny and long bone histology of the Middle Triassic (?late Anisian) dinosauriform Asilisaurus kongwe and implications for the growth of early dinosaurs

    Griffin, C. T., and S. J. Nesbitt. 2016. The femoral ontogeny and long bone histology of the Middle Triassic (?late Anisian) dinosauriform Asilisaurus kongwe and implications for the growth of early dinosaurs. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1111224.

    http://www.tandfonline.com/doi.....16.1111224

    English is not my first language and I’m not familiar with the terminology in paleontology.
    Can anyone tell what that term means?
    Thanks.

    (?late Anisian) ?

    what does the term “(?late ” mean in this case?
    what’s the ‘?’ after the open parenthesis and before the word ‘late’ supposed to indicate?

  3. 3
    Zachriel says:

    Dionisio: Can anyone tell what that term means?

    Asilisaurus dates to the Middle Triassic epoch. The exact geological age is uncertain.

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