Tetrapod Zoology

Yay: day…. err, 4 of Stuffed Megamammal Week (day 1: Khama, day 2; Eland, day 3: Okapi). And now for something completely different… a perissodactyl. Specifically, a rhino and, more specifically still, the weirdest rhino of them all (among extant forms at least): the Sumatran rhino Dicerorhinus sumatrensis. You might have noticed that the claim made earlier in the week that I would go all ‘text-lite’ for a while hasn’t really panned out, so this time I’m going to make a real concerted effort to add nothing new. The good news is that I previously produced a long article on the Sumatran rhino back here on ver 1, so all I’m going to do here is recycle some of that text…

A small, two-horned species, the Sumatran rhino has long, shaggy reddish-brown fur covering its body and limbs. ‘Small’ for a rhino means that it is about 3 m long, 1-1.5 m tall at the shoulder, and between 800 and 2000 kg in weight. It has large lower canines (but no upper canines) that it uses in combat and both horns are (typically) short, the second (aka frontal) may be so low that it is barely more than a bump. A few individuals have been recorded with very long nasal horns of nearly 40, and even nearly 70, cm long.

It seems inevitable that, whenever Sumatran rhinos are mentioned, that old chestnut about them being a ‘living fossil’ is trotted out. Sumatran rhinos have been thought of as ‘living fossils’ because – supposedly – they belong to a particularly old group, the group they belong to was particularly conservative throughout its history, and they are anatomically archaic. Ignoring for a moment the fact that the species itself appears to be geologically young, these assumptions are no truer for Sumatran rhinos than they are for a great many other living tetrapods, and at worse they are just plain wrong. Dicerorhinus is NOT particularly old, it was NOT particularly conservative, and it is NOT particularly archaic in terms of anatomy! And if you want to argue that it is (in answer to all of the above), then I demand that Bottlenose dolphins and Peacocks and scores of other tetrapods now be consistently referred to as ‘living fossils’ too, forever more. For a far longer, more detailed version of this rant, see the ver 1 post.

Why is the stuffed specimen – again, photographed at the National Museum of Ireland in Dublin – so dark when the animal is reddish-brown when alive? I think it’s been painted, and (judging from its shininess) it’s also been varnished. Its notably blunt, heavily keratinised snout is distinctive and very different from what’s present in the two Rhinoceros species (the Great Indian and Javan). I’d like to know why the anterior horn in this individual was, apparently, worn down to a rounded stump. Alas, I know nothing about the individual I show here.

And that’s that. Another one tomorrow!

For previous Tet Zoo posts on rhinos see…

Comments

#1 Sordes
April 9, 2009

Could it be that this particular rhino lived for some time in captivity and abrased its horn in a cage or at a wall? BTW, I was also in the National Museum of Dublin many years ago, but I haven´t seen any stuffed animals there, only historical and archeological artefacts.
#2 Metalraptor
April 9, 2009

From the pictures there, this rhino almost looks fake, like some sort of oversized plastic model.
#3 Hai~Ren
April 9, 2009

Ah yes, the most distiinctive extant rhino.

There’s a mounted Sumatran rhino head at the public gallery of the Raffles Museum, and it is really quite hairless. So is this one, although it looks as if it was covered in a thick coat of varnish or lacquer. I wonder if it’s a common trait for Sumatran rhino museum specimens to end up looking losing all their hair.

As an aside, it’s shocking to see how much the Asian rhino species have declined, especially the Sumatran and Javan rhino. Consiering that both species were found across much of mainland Southeast Asia and the Sunda Islands in recent history, the fact that they have been reduced to tiny fragmented populations is just depressing. I know the Burmese subspecies of Sumatran rhino is supposedly extinct, and I’m wondering just how much longer it’s going to take before the Vietnamese populations of Javan rhino dies out.
#4 gordon rugg
April 9, 2009

The horn may have been removed post mortem in the field, with the stub being scraped for rhino horn shavings. I’ve seen reports of local skinners removing assorted body parts from different animal types for various reasons; for instance, the belief in some places that leopard whiskers could be used by magicians to poison people, so the skinners would remove leopard whiskers and burn them when skinning a leopard carcass. Removing a rhino horn from the carcass would reduce the risk of thieves trying to pilfer the skin during transit. No idea why the museum wouldn’t fit a replica horn over the stub, though, unless they thought it was supposed to look like that.
#5 Brian Beatty
April 9, 2009

I think my favorite thing about the Sumatran rhino is the way people in zoos think that its furriness indicates that it is an old or sick rhino. It is interesting to consider how the skin and fur of Dicerorhinus may or may not be similar to that of fossil rhinos…. if you look at the way brontotheres used to be illustrated by Osborn (in his titanothere monograph, for instance), you see the same sort of hairiness one sees in Dicerorhinus, with an added hint of Clydesdale horse ankle hair.
If one optimizes it on a cladogram of Perissodactyla, they probably had short hair like one sees in horses today, with some regions of longer hair on the neck and limbs. So, it would make sense to reconstruct most perissodactyls with some sort of short, coarse hair.
But in the BBC’s ‘Walking with prehistoric beasts’, they reconstructed brontotheres as having African rhino-like skin. Though thermoregulatory matters might trump parsimony, most places that brontotheres are from were seasonal. The best reconstruction of a brontothere I’ve seen is the one being described by Matt Mihlbachler and Tom Demere, for which a model has been made for the SDNHM. A link to images of it by the artist can be seen at his website here:
http://www.studiomonteleone.com/gallery_md.html
I must admit, seeing Hydrodamalis with it on this page is a plus, but I guess I’m biased.
Brian
#6 Jorge Velez-Juarbe
April 9, 2009

Thanks for sharing that link Brian! Although that’s a very nice reconstruction of a brontothere, I must say that I was far more entertained with their Hydrodamalis cuestae, specially with how they reconstructed the limb, fingerless, like in H. gigas.
#7 Moro
April 9, 2009

Maybe a lot of people just rubbed its nose for good luck.
#8 Rob Deegan
April 9, 2009

@ Sordes. “The National Museum of Ireland is split up into 4 parts, 3 of which are in Dublin. The museum on Kildare Street is the National Museum of Ireland – Archaeology and History.” That’s the one that you saw. A couple of blocks away is the Natural History Museum which is where Darren took his photos. The Natural History Museum was a favorite hang-out for me as a child. I was particularly impressed by the giant elk and by specimens of recently extinct (in Ireland) raptors such as common buzzard, red kite and golden eagle. These are currently being reintroduced (the raptors, not the elk!).
#9 Jorge Velez-Juarbe
April 9, 2009

The Natural History Museum in Ireland is currently closed. Roof collapse I think it was. I was in Dublin 2 months ago and really looking forward to visit this museum, fortunately there are many other things to see in that city and at least I’m getting to see some of their stuffed mammals, so, thanks Darren!
#10 Sordes
April 10, 2009

Thank you for this information Rob! I even did not know at this time that there was a NHM at Dublin, because it was not listed in the guides for attractions we had at this time. I had anyway comparably little time to visit such attractions like the National Museum because it was a field excursion in the 13th. class, and most places we visited were part of a program or things like the Guiness brewery I visited with some classmates. At the last day I went alone to the Natinal Museum because nobody else was interested in this. But even if it houses no zoology-related stuff, the archeological artefacts are really amazing, especially the old celtic gold jewelry. I think I have never seen so much pure gold on one place. The skills of this ancient goldsmiths were really amazing. Sadly this was long before the time of common use of digital cameras.
#11 JuliaM
April 10, 2009

Caught some film of one of these not 5 hours ago, on the satellite channel ‘Eden’. They were showing a repeat of the ‘Monsters We Met’ series, and I tuned in just as they were covering human-driven extinctions.

The narrator said that this animal was known as the ‘living dead’, because its population was now so low, extinction was now certain. Sad…
#12 William Miller
April 10, 2009

I wonder how they can say its extinction is certain? Sounds defeatist … some species have been saved from tiny genepools (Chatham Islands Black Robin, from a total population of 5 – including only one female!)
#13 Boesse
April 12, 2009

Darren,

Wish I had seen this a couple days ago. In response to some of those marine mammals as living fossils in your original post on Dicerorhinus, In any event, the oldest records of Tursiops are from the Pliocene of the Mediterranean and west Atlantic; Orcinus is known (at the earliest) from the late Pliocene, and Balaenoptera/Megaptera are known (at the earliest) from the latest Miocene (<6 Ma).

Older records abound in older literature; this is due (in part) to earlier workers referring material (complete or incomplete) to modern genera, whether 1) the material was complete and did not actually resemble the extant genus or 2) the material was too incomplete to identify correctly. Both the delphinid and balaenopterid fossil records are in dire need of revision (although this has already been undertaken for the Plio-Pleistocene delphinid record of Italy – see Bianucci, 1996; also, for the beginnings of balaenopterid revisions, see Demere 1986, Demere et al. 2005, and Bisconti 2007)

Refs:
Bianucci, G. 1996. The Odontoceti (Mammalia, Cetacea) from Italian Pliocene systematics and phylogenesis of Delphinidae. Palaeontolographia Italia 83:73-167

M. Bisconti. 2007. Taxonomic revision and phylogenetic relationships of the rorqual-like mysticete from the Pliocene of Mount Pulgnasco, northern Italy (Mammalia, Cetacea, Mysticeti). Palaeontolographica Italica 91:85-108

Demere, T.A. 1986. THE FOSSIL WHALE, BALAENOPTERA DAVIDSONII (COPE 1872), WITH A REVIEW OF OTHER NEOGENE SPECIES OF BALAENOPTERA (CETACEA: MYSTICETI). Marine Mammal Science 2:277-298

Deméré, T.A., A. Berta, and M.R. McGowen. 2005.
The taxonomic and evolutionary history of fossil and modern balaenopteroid mysticetes. Journal of Mammalian Evolution 12:99-143
#14 jaredleeper
April 15, 2009

You should here this animal vocalize. You would understand why the snout is rounded like that. The snout feels almost hollow (YES! I have had the pleasure of touching a live S. Rhino and yes I am bragging about it).
#15 Darren Naish
April 15, 2009

Wow, you lucky. I’ve been told that the snout feels as if the whole thing is covered in keratin.
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