Laelaps

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The giraffe-like restoration of Paraceratherium, from Natural History.

If I believed everything Hollywood told me I would accept that a paleontologist is someone who has a knack for finding numerous exceptionally-preserved, fully-articulated skeletons. The truth of the matter, however, is that most fossil creatures (at least as far as vertebrates are concerned) become known to science in bits and pieces. This was the case with the largest land mammal that ever lived, Paraceratherium.*

*[There is some controversy surrounding the name of this beast. At present paleontologists are still debating whether the bones of this mammal should be called Paraceratherium, Baluchitherium, Indrichotherium, or in what combination can these names might be synonymized. For now I will call the animal Paraceratherium as this name was published first and a solid case for two or three distinct genera of giant indrichothere that lived in the same place at the same time has yet to be made.]

For such a large animals, about 16-18 feet high at the shoulder, there seemed to be very little left of the Paraceratherium that once roamed much of Asia. When its remains first came to the notice of scientists at the beginning of the 20th century there was very little to go on. A note that appeared in a 1920 issue of Science, for instance, described how it was an enigmatic creature whose scant remains most resembled a rhinoceros but little else. This relationship was reinforced when a partially-complete skull of the animal was brought back to the American Museum of Natural History in 1922, but just how rhino-like was Paraceratherium?

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The rhino-like restoration of Paraceratherium, from Popular Mechanics. I think the man in the restoration is placed in a rather unenviable position.

There were two different models. The first was dashed off soon after the AMNH skull was restored and envisioned Paraceratherium as an enormous, hornless rhino. The body outline gave it a short, flabby neck and a pot belly, and this seemed appropriate enough if the animal truly was a giant rhinoceros. This illustration was quickly abandoned, however.

Although he does not state the reasons for his change of mind, in a Natural History article paleontologist H.F. Osborn noted that he drastically changed his ideas about the proportions of the animal in 1923. (I assume this is due to the incorporation of other evidence, such as huge neck vertebrae found from the same parts of Asia.) This new restoration gave Paraceratherium a giraffe-like neck and a taller stature, an increase of two to four feet at the shoulder over the previous restoration.

More fossil evidence would show this latter view to be the correct one, but it can be difficult to withdraw popular paleontological images once they have been popularized. A July 1923 issue of Popular Mechanics (published three months after Osborn’s revision), for instance, restored Paraceratherium in the short, squat rhino mode. This view eventually faded, especially since Paraceratherium was not a rhino per se but merely closely related to rhinos, and now the long-necked restoration graces museum halls and the paleontological books.

Comments

  1. #1 wolfwalker
    May 15, 2009

    That Pop Mechanics reconstruction looks unrealistic to my eye, even if I didn’t know there was good fossil evidence for Paraceratherium being long-necked. The equal-size fore- and hindquarters put the center of mass somewhere near the back of the ribcage. The thick neck and big head stuck way out in front of the animal make it look off-balance, a lot of extra mass in front and nothing to balance it behind. Look at the modern rhinoceros right next to it: you can see the rhino has substantially altered its physique, using that huge shoulder hump to move the center-of-mass forward so that the hindquarters become the balance for the head. A rhino-proportioned Paraceratherium would have to do something similar. Would you agree?

  2. #2 Lilian Nattel
    May 15, 2009

    Really interesting to see how the imagined shape of this creature has evolved.

  3. #3 Raymond Minton
    May 15, 2009

    Alexander, in his book about the biomechanics of extinct animals, also had Paraceratherium with a bulky body build, rather like that of a buffalo,rather than the more svelte design it’s depicted with now (and which obviously affected weight estimates.)

  4. #4 Allen Hazen
    May 16, 2009

    Uncertainty about the animal’s proportions has certainly contributed to the uncertainty about its size. Leading to one of my all-time favorite journal article titles: “On the largest land mammal ever imagined”! (“Zool. J. of the Linnean Soc.” a decade or so back: authors went for a low weight estimate and concluded that Parindricobaluch was probably not much larger than the largest Proboscideans.)

  5. #5 resimleri
    May 16, 2009

    Alexander, in his book about the biomechanics of extinct animals, also had Paraceratherium with a bulky body build, rather like that of a buffalo,rather than the more svelte design it’s depicted with now (and which obviously affected weight estimates.)

  6. #6 Dartian
    May 18, 2009

    Allen:

    Leading to one of my all-time favorite journal article titles: “On the largest land mammal ever imagined”! (“Zool. J. of the Linnean Soc.” a decade or so back

    The paper you are referring to is Fortelius & Kappelman (1993). As for its title, I think it was at least partly in response to an earlier paper with the title “The largest land mammal” (Economos, 1981). Economos estimated, on theoretical grounds, a maximum weight of 20 t for this beast. Fortelius & Kappelman reached a similar weight estimate empirically.

    References:

    Economos, A.C. 1981. The largest land mammal. Journal of Theoretical Biology 89, 211-215.

    Fortelius, M. & Kappelman, J. 1993. The largest land mammal ever imagined. Zoological Journal of the Linnean Society 108, 85-101.

  7. #7 Katielly Lanzini
    January 9, 2010

    The size of the skull, of course, the more modern concept of Paraceratherium seems to be appropriate and correct. The animal is really fantastic. Work as a paleo-Arctic and a time like this I’ll face the challenge of building a replica with the fleshy look of the animal

  8. #8 sirps
    February 8, 2011

    So is Paraceratherium the biggest mammal ever to walk around our planet?

  9. #9 Cal Lewis, M.D.
    March 28, 2012

    Smithsonian has an article on “paraceratherium” a hornless rhino called “hyracodonts” I’m tryng to connect the paraceratherium to the Hyrax which is widely touted to be the “closest living relative of the elephant” based mostly I guess because the male Hyrax has no scrotum but has its testicles next to the kidneys “AS DOES THE ELEPHANT” Pretty shaky evidence for a close relative. What’s your take on the jump from “hyracodont” to Hyrax?