The monster sheep that wasn't, and other tales of African Bovini

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If you're a regular reader you'll have seen the recent article on those African 'great bubalus' depictions and on how they might (or might not) be representations of the large, long-horned bovin bovid Syncerus antiquus. As discussed in that article, S. antiquus - long thought to be a species of Pelorovis - is now regarded as a very close relative of S. caffer, the living Cape buffalo. As usual though, there are quite a few additional things that I wanted to cover, so here's an attempt to tie up various loose ends [the illustrations above show radically different reconstructions of Pelorovis oldowayensis. Read on for explanation].

So, the type species for Pelorovis is P. oldowayensis, a large, long-faced bovid with horns that are placed well posteriorly. They curve backwards and outwards before curving forwards. It seems to have been similar in proportions to other bovins but for its longer distal limb segments, and of course its antelope-like face and horns are rather different from those of other species too. Compared to other big bovins, P. oldowayensis wasn't really a 'giant' - it was big, with a shoulder height of 1.5 m, but remember that there are living bovines (like the Gaur Bos gaurus) where shoulder height can be 2.2 m. If you need a refresher, Gaurs (and Bantengs B. javanicus) were covered on Tet Zoo in April 2009.

The horns are present in both sexes, with those of assumed females being shorter and more sharply curved than those of assumed males. Unlike those of other bovins, the horns are solid, and they (viz, the horncores) sometimes possess a deep groove that extends along the outside curve (Gentry 1967). Whether this affected the shape of the horn sheaths is unknown.

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Today it's widely accepted that P. oldowayensis is a member of Bovini, and in fact recent work indicates that it's the closest relative of Bos (MartÃnez-Navarro et al. 2007). MartÃnez-Navarro et al. (2007) actually argued that P. turkanensis from the Late Pliocene, P. oldowayensis from the Pleistocene and Bos primigenius (the Aurochs) represent 'chrono-species' of the same lineage, in which case Pelorovis should be sunk into Bos [the adjacent figure - from MartÃnez-Navarro et al. (2007) - shows how various bovin species grouped together following an examination of various anatomical landmarks. Note the presence of a Leptobos-Bison grouping and a Pelorovis-Bos grouping]. This phylogenetic hypothesis has some interesting biogeographical implications, suggesting that Bos originated in Africa before spreading into the Middle East (during the Early Pleistocene) and Europe (during the Middle Pleistocene). Previous scenarios identifed Asian bovin taxa (in particular Leptobos of the Miocene, Pliocene and Pleistocene of Eurasia) as the closest relatives of Bos.

Anyway, the characteristic and unique horn form of P. oldowayensis was initially thought to evidence an affinity with sheep and goats - indeed, you might have noticed that Pelorovis means 'monster sheep'. Hans Reck, the original describer of the species, "chose the sheep as being least far phylogenetically from Pelorovis, but was aware that the East African animal could have evolved its horn shape in isolation from other known living or fossil sheep" (Gentry 1967, p. 246). Gentry (1967) showed by way of careful and thorough comparison that P. oldowayensis is a member of Bovini and not a close relative of sheep.

The monster sheep that wasn't

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But back when Reck's idea was regarded as correct, the incredible size of P. oldowayensis relative to other sheep was startling and unexpected. In reconstructions, artists hoped to show how peculiar it might look: my favourite is the one here. Featuring a modern Mouflon Urial for scale, it essentially makes P. oldowayensis look like a giant, smooth-horned mouflon urial.

The artist had evidently received a brief description but hadn't been able to look at fossils (or pictures of them). I'm afraid I don't know the original source of this painting - I've only ever seen it in my tattered Figurine Panini Prehistoric Animals sticker book, published 1982.

There's another peculiar reconstruction out there, this time by Michael R. Long and appearing in Robert Savage's Mammal Evolution: An Illustrated Guide. The animal looks a bit like a Cape buffalo but has a shaggy pelt, and I always used to wonder whether the artist had been trying to make the animal look goat-like. Long's mammal reconstructions get used quite a lot - partly because he illustrated species that haven't been illustrated by others, and partly because the Natural History Museum in London uses various of the illustrations on its web site - but I have to say that I don't like them much.

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Having mentioned Cape buffalo and shaggy coats, it's worth using this as another opportunity to note how variable S. caffer (sensu lato) really is. We typically think of it as a big, black, short-coated animal of hot grasslands, but don't forget that there are smaller, longer-coated, reddish/brownish forms that inhabit woodlands and forests. In the big savannah forms (S. c. caffer) the horns are massive, form an enormous boss in the midline, and curve strongly upwards at their tips. In the small forest form (S. c. nanus), the horns are much shorter, don't form a central boss, and curve backwards with little upwards curvature. The two forms are so different that possible separate species status has been suggested even in recent years (Groves 2000); complicating things is the fact that there are apparent intermediate forms (like S. c. cottoni and S. c. mathewsi) (Grubb 1972) [the adjacent figure - from Grubb (1972) - shows (clockwise from top left) S. c. caffer from Uganda, S. c. caffer from Kenya, S. c. mathewsi, S. c. nanus (at very bottom), and S. c. cottoni (at bottom left)].

Ribbed horns in Syncerus and reversing an opinion, perhaps

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There's one more thing about these bovins that I want to get out of the way. The previous article included some discussion of the fact that various pieces of north African rock art (like the one included here) show large bovins with long, vertically ribbed horns. This animal is the 'Great bubalus', long thought to be a representation of S. antiquus.

Because that vertical ribbing reminded me a lot of Asian water buffaloes (Bubalus), I suggested in the previous article that the 'Great bubalus' depictions might not be of S. antiquus after all. Rather, could they be representations of wayward Asian water buffaloes instead? I did note that this identification was problematic, since osteological evidence pointing to the presence of Asian water buffaloes in north Africa is, at best, a couple of thousand years old (and hence not really old enough to match the 'Great bubalus' depictions: they're more like 4000 years old).

As you'll know if you've been following the comments attached to the previous article, vertical ribbing is not, however, altogether unheard of in modern S. caffer (regular Tet Zoo commenter Jerzy has been linking to various online photos). Interestingly, some particularly long-horned S. caffer individuals show several vertical ribs along their horns (Grubb 1972). This hints at the possibility both that Syncerus has the potential to produce strongly 'ribbed' horns, and that an especially long-horned Syncerus might have particularly elaborate ribbing.

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In view of all of this, I'm thinking that the 'Asian water buffalo in Africa' hypothesis is looking weaker, and that those long-horned 'Great bubalus' animals shown in the rock art are S. antiquus after all. After I published my article I dug out my cherished copy of Alan Turner and Maurico Antón's excellent Evolving Eden: An Illustrated Guide to the Evolution of the African Large-Mammal Fauna (unfortunately out of sight high on a shelf while I was preparing that first article, and hence out of mind) (Turner & Antón 2004). While Antón illustrated P. oldowayensis with smooth horns, he gave his S. antiquus vertically ribbed horns, just like the 'Great bubalus' in the rock art [his illustrations of both species are shown above, with a Cape buffalo next to the P. oldowayensis]. I don't know, however, whether he was aware of the rock art and hence gave his S. antiquus ribbed horns for this reason, or if he gave it ribbed horns because he wanted to make it look Bubalus-like: Turner & Antón (2004) state "[I]ts similarity to the water buffalo is much greater than [is] its resemblance to the other Pelorovis species" (p. 167). Maybe I should ask him.

We'll leave Pelorovis and Syncerus alone for now. There are still many other issues concerning African bovid diversity that I'd like to cover. And, look, I've gone to some trouble to collect much of the relevant literature...

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And for more on other artiodactyls, see...

Refs - -

Gentry, A. W. (1967). Pelorovis oldowayensis Reck, an extinct bovid from East Africa. Bulletin of the British Museum (Natural History), Geology, 14, 245-299.

Groves, C. P. 2000. What are the elephants of west Africa? Elephant 2, 7-8.

Grubb, P. 1972. Variation and incipient speciation in the African buffalo. Zeitschrift für Säugetierkunde 37, 121-144.

MartÃnez-Navarro, B., Pérez-Claros, J. A., Palombo, M. R., Rook, L. & Palmqvist, P. 2007. The Olduvai buffalo Pelorovis and the origin of Bos. Quaternary Research 68, 220-226.

Turner, A. & Antón, M. 2004. Evolving Eden: An Illustrated Guide to the Evolution of the African Large-Mammal Fauna. Columbia University Press, New York.

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In Brazil this Figurine Panini Prehistoric Animals sticker book was translated and published. I had this book, and still have same old pages.

By J. S. Lopes (not verified) on 03 May 2011 #permalink

I too still have my cherished copy of the Panini Prehistoric animals sticker album - it is a masterpiece. Can't quite recall whether I completed it though. Those darned sticker albums - always left you with a huge pile of swaps when you were desperately searching for the last few stickers.

By RStretton (not verified) on 03 May 2011 #permalink

Nice post. Good work collecting all that hard-copy (!) literature. Is most of the literature old, and fairly sparse, or not? I wonder if the dates and biogeography of African bovins are mostly settled, or whether hominin paleontology of the Plio-Pleistocene has drawn most of the attention...or whether the former is true because of the latter.

Also, these Figurine Panini books appear to be full of win.

I was just looking at my Panini book the other day! Some of the illustrations were really quite good, others not so much, and there are a few descriptions that seem to be a bit off too. Either way, it's a shame I never put more effort into completing the sticker collecting since it's only half full. :(

needz moar turtlz

By Sven DiMilo (not verified) on 03 May 2011 #permalink

Featuring a modern Mouflon for scale

That looks more like an argali to me. The colouration is wrong for a European mouflon (in particular, the animal lacks a white 'saddle') and the horns are rather untypically large. I would suspect that the artist intended to compare Pelorovis with the largest extant sheep, i.e., the argali.

Panini Prehistoric Animals sticker book, published 1982

Is it originally Italian? Italian artists/authors/editors would presumably be familiar with European mouflons and not confuse them with argalis; could this simply be a case of something having been lost in translation* to English? Or alternatively, perhaps there has been some taxonomic confusion? In some classifications, the argali has been considered conspecific with the European mouflon.

* In some languages, e.g., French, 'mouflon' is a fairly generic name for various wild sheep (the North American bighorn sheep, for example, is mouflon canadien in French).

out of sight high on a shelf while I was preparing that first article, and hence out of mind

D'oh! I own Evolving Eden too, but it never occurred to me to check it out.

Well, the horns in the rock carving curve upward, those of Pelorovis oldowayensis curve downward, and those of Syncerus antiquus curve upward...

needz moar turtlz

needz moar temnospondlz

By David MarjanoviÄ (not verified) on 03 May 2011 #permalink

David: the rock art is mostly regarded as representing Syncerus antiquus - no one is saying that it might be Pelorovis. I was suggesting that, rather than being S. antiquus, the rock art might depict Bubalus.

Thanks for clearing up the supposed double identity of *Pelorovis* as both a buffalo and a sheep! I too remembered the picture from the sticker album. Inaccurate or not, I really like it.

Anyhow, I have very mixed feelings about 'Evolving Eden'. One one hand, all the artwork (with the exception of the crowned eagle carrying a young australopithecine) is superb. On the other hand, I think that as far as text goes, it's very subpar and certainly disappointing compared to 'Mammoths, sabertooths and hominids'. When I first got it, I could hardly believe that many clades of fossil African mammals were dealt with in just two or three sentences.
In fact, this disappointment was the main motivation for me to get 'Cenozoic mammals of Africa'. Perhaps my expectations are unrealistically high, but that book sort of disappointed me too, though much less. I'd have preferred more discussion of prehistoric ecologies and straightforward descriptions of the evolutionary pathways of fossil African mammals over endless descriptions of teeth. I know that for mammal paleontology, teeth are extremely important but still...

I'm afraid I don't know the original source of this painting - I've only ever seen it in my tattered Figurine Panini Prehistoric Animals sticker book, published 1982.

Panini had something of a questionable reputation regarding their sticker artwork. For the most part, they used extant artwork as a source, and had it recreated by local, uncredited artists to save money - said recreations spanning the range from 'considerably inspired by a single source' to 'blatant rip-off'. The Italian artists likely worked on a tight schedule for very little money, so I doubt many of them were motivated to invest a lot of research beyond the information or references they were given.

By Phillip IV (not verified) on 03 May 2011 #permalink

As far as I can remember, the "mouflon" in the Panini book was identified as an argali in the Norwegian translation.

I'm silly, of course it's meant to be an Argali - and possibly a Marco Polo argali or Pamir argali, the form usually (though perhaps incorrectly) said to be the largest of living sheep (even though the colour is probably off). I just looked at the colour and assumed Mouflon.

Needz moa moa

Kreh:

That drawing on the stone, it looks like a Tamaraw.

Not really; the tamaraw (a.k.a. the Mindoro dwarf buffalo) typically has very short horns.