I’m out in the field tomorrow: whether I blog on what happens will depend on… what happens. Think snakes, sea caves and mammal tracking. Until then, here is a mystery…
What do these horns belong to? They’re part of Jon McGowan’s collection: he acquired them some years ago from an antique shop (the same sort of place where he previously obtained a head of the remarkable Osborn’s caribou), so provenance data of any sort is lacking. While this animal is clearly a bovid, beyond that we’re having trouble identifying it. As you can see from the ruler, it’s not particularly big: we estimate that the animal was about the size of a domestic goat or serow. Judging by the interdigitation of the sutures and the ‘worn’ look to the transverse ridges of the horns, this was probably a mature animal and not a juvenile. Several features make this animal unusual. While its horns are not exceptionally long, they possess particularly prominent transverse ridges and curve gently outwards at their tips. The supraorbital foramina appear proportionally large and are set within large, oval fossae [see close-up image below].
For those who know about the Pseudonovibos controversy, I will add that the natural wear and tear on the horn surfaces shows that there is no way that their shape has been modified by heating or bending (those that don’t know what I’m getting at will either have to be very patient or check out the literature: Macdonald & Yang 1997, Brandt et al. 2001, Hassanin et al. 2001, Kuznetsov et al. 2001, Thomas et al. 2001, Timm & Brandt 2001, Feiler et al. 2002).
In the following discussion, I haven’t deliberately attempted to go through the various bovid clades in any sort of phylogenetic pattern: there are several different views on how bovids should be classified and divided but most recent studies (Hassanin & Douzery 1999, 2003, Ropiquet & Hassanin 2004) have found support for the fairly traditional view that Bovidae includes a Bovinae (cattle, boselaphines and tragelaphines) and an Antilopinae (gazelles, sheep, goat antelopes and kin, wildebeest and hartebeest, oryxes and sable antelope, and others). When making my comparisons, I had Walker’s Mammals of the World, Sixth Edition and David Macdonald’s The New Encyclopedia of Mammals to hand.
Cattle are out as they lack prominent transverse ridges and the whopping great big supraorbital foramina present in this animal. Some duikers possess transverse ridges, but none have out-curving horns nor large supraorbital foramina so far as I can tell. Duikers are also big brained (among antelopes they actually have, proportionally, the biggest brains of all, this despite the fact that they’re apparently ‘primitive’) and their frontal regions tend to have an inflated look that isn’t present in the mystery bovid. The horns of the mystery bovid lack the spiralling present in tragelaphines, and no tragelaphine has true transverse ridges. It’s not a Nilgai Boselaphus tragocamelus as they have smooth horns and many other differences [adjacent image shows nilgai skull].
Comparisons with reduncines (the clade that includes waterbuck, lechwe and so on) might look promising given the prominent transverse ridges present in members of this group, but again none of the species have horns that curve outwards. Reedbuck Redunca fulvorufula [shown in adjacent image] have horns that are rather similarly proportioned to the horns of the mystery bovid, and reedbuck horns also possess similar transverse ridges. However, in reedbucks the horns curve forwards and slightly inwards, not strongly outwards. I think that hippotragines – the oryxes, sable antelope and so on – are also out as no species has the relatively stout horns of the mystery bovid, nor do their horns curve outwards. Alcelaphines (hartebeest and wildbeest) also lack species that resemble the horns of the specimen. Dik-diks, grysboks, dwarf antelopes and klipspringers and so on are also out.
Gazelles are their kin (antilopines) include species with similarly proportioned horns, many of which exhibit transverse ridges like those of the mystery bovid. I have yet to see any species where the horns curve outwards as they do in the mystery bovid however, or where the supraorbital foramina are either as large as they are in the mystery bovid, or set within the same sort of shallow fossae, but that doesn’t mean that such a species doesn’t exist. Saiga horns don’t sweep laterally.
Finally, what about caprines? This is where the affinities of the animal most likely lie, but having said that we’ve still failed to find a match. Sheep are out for the same reason as many of the other groups I’ve mentioned so far: in sheep, the supraorbital foramina are not as proportionally large as they are in the mystery bovid, nor are they set within such large fossae. Goats (including ibex, markhor and turs), bharals and the Barbary sheep Ammotragus are highly similar to sheep in these features (so far as I can tell) and don’t particularly resemble the mystery bovid [adjacent image shows Pakistani markhor Capra falconeri. What an amazing beast].
What about serows Capricornis and gorals Naemorhedus. Nope, as in neither do the horns sweep outwards. Radically different horn morphologies are exhibited by American mountain goat Oreamnos, chamois Rupicapra and musk ox Ovibos. It can’t be a takin Budorcas as their horns always begin to curve laterally right near their bases, whereas in the mystery bovid the lateral curvature only occurs near the tips, and in takin the horn bases are very close together (in the mystery bovid they are well apart). Tahr Hemitragus possess laterally compressed horns that lack prominent transverse ridges [image below shows Arabian tahr H. jayakari].
And that’s it. I remain stumped. Is it some sort of obscure gazelle that is hardly ever/never illustrated in the literature or is it an aberrant caprine? Those are my best guesses but, as noted, even they don’t fit entirely. As yet, we haven’t done any of the proper sorts of comparisons that are needed to go further on the specimen: on the ‘to do’ list is a visit to a comprehensive bovid skull collection (e.g., that at the Natural History Museum, London). I know that there are a few bovid gurus out there that can perhaps provide an answer to our conundrum, so if you’re available to help please do. The danger in asking for help like this is that you can always come away from the experience looking dreadfully inexperienced and naive. But, then, I never pretended to be a bovid expert.
In other news, I have added some new stuff to the biography page, and observant readers may have noticed that the profile is now different. Yes, things they are a-changing.
Refs – –
Brandt, J. H., Dioli, M., Hassanin, A., Melville, R. A., Olson, L. E., Seveau, A. & Timm, R. M. 2001. Debate on the authenticity of Pseudonovibos spiralis as a new species of wild bovid from Vietnam and Cambodia. Journal of Zoology 255, 437-444.
Feiler, A., Ziegler, T., Ansorge, H. & Nadler, T. 2002. Pseudonovibos spiralis – Mythos oder Wirklichkeit? ZGAP Mitteilungen 18, 21-24.
Hassanin, A. & Douzery, J. P. 1999a. Evolutionary affinities of the enigmatic saola (Pseudoryx nghetinhensis) in the context of the molecular phylogeny of Bovidae. Proceedings of the Royal Society of London B 266, 893-900.
– . & Douzery, J. P. 1999b. The tribal radiation of the family Bovidae (Artiodactyla) and the evolution of the mitochondrial cytochrome b gene. Molecular Phylogenetics and Evolution 13, 227-243.
– ., Seveau, A., Thomas, H., Bocherens, H., Billiou, D. & Nguyen, B. X. 2001. Evidence from DNA that the mysterious ‘linh duong’ (Pseudonovibos spiralis) is not a new bovid. Comptes Rendu de l’Academie des Sciences, Paris, Sciences de la vie 324, 71-80.
Kuznetsov, G. V., Kulikov, E. E., Petrov, N. B., Ivanova, N. V., Lomov, A. A., Kholodova, M. V. & Poltaraus, A. B. 2001. The ‘lin duong’ Pseudonovibos spiralis (Mammalia, Artiodactyla) is a new buffalo. Naturwissenschaften 88, 123-125.
Macdonald, A. A. & Yang, L. N. 1997. Chinese sources suggest early knowledge of the ‘unknown’ ungulate (Pseudonovibos spiralis) from Vietnam and Cambodia. Journal of Zoology 241, 523-526.
Ropiquet, A. & Hassanin, A. 2004. Molecular phylogeny of caprines (Bovidae, Antilopinae): the question of their origin and diversification during the Miocene. Journal of Zoological Systematics & Evolutionary Research 43, 49-60.
Thomas, H., Seveau, A. & Hassanin, A. 2001. The enigmatic new Indochinese bovid, Pseudonovibos spiralis: an extraordinary forgery. Comptes Rendu de l’Academie des Sciences, Paris, Sciences de la vie 324, 81-86.
Timm, R. M. & Brandt, J. H. 2001. Pseudonovibos spiralis (Artiodactyla: Bovidae): new information on this enigmatic South-east Asian ox. Journal of Zoology 253, 157-166.