As usual, pressures of work and such mean that I haven’t had time to put anything special or extensive together, but I thought it might be appropriate to say a few things about fossil tapirs [photo at top by Darren Naish; see if you can guess what’s going on]. After all, there are an awful lot of them, and there’s very little useful information about them online. The text here is culled from my textbook project (go here on patreon for more about it) and only concerns tapirs of modern sort: that is, the members of the genus Tapirus. There are lots of other fossil tapirs but I’m going to ignore them here, sorry. For those of you who know anything about fossil tapirs, I hope you’ll forgive me for ignoring the taxonomic issues concerning Tapiravus and Tapiriscus.

A few tapirs, ancient and modern. These images - and many others of perissodactyls and other animals - are from my planned textbook and first appeared at the Tet Zoo patreon.

Tapirus is known from the Miocene onwards and more than 15 extinct species are currently recognised. Because these species appear more or less simultaneously in North America, Europe and Asia, the origins of Tapirus are somewhat murky. However, the presence of several Tapirus-like tapirs belonging to Protapirus, Paratapirus and Eotapirus in the Oligocene and Miocene of France and Switzerland (Scherler et al. 2011) suggest European origin.

Tapirs in France, in Italy, in Hungary, in the Balkans! Tapir history in the Miocene of Europe (and now speaking of Tapirus alone) is quite complex. The group repeatedly disappears and reappears, apparently as a consequence of local extinction followed by reinvasion from elsewhere. Indeed, there is a so-called ‘tapir vacuum’ just after the Lower Miocene that is soon filled (Van der Made & Stefanovic 2006). European tapirs then persisted across the Miocene-Pliocene boundary, T. arvernensis being abundant at several French and Italian sites of Pliocene age.

Partial skull and mandible of T. arvernensis at the Museo di Paleontologia di Firenze. Image by Ghedoghedo, CC BY-SA 3.0.

Other fossil European tapirs are known, including T. jeanpiveteaui from the Pliocene of France, the dwarf T. pannonicus from the Miocene of Bosnia and elsewhere, T. balkanicus from the Upper Miocene of Bulgaria and T. hungaricus from the Miocene of Hungary. T. hungaricus is more ‘advanced’ than other European tapirs in the degree of ‘molarisation’ of its premolars and is regarded as distinct enough from other Tapirus species to deserve its own subgenus: Meyeriscus (Spassov & Ginsburg 1999). Climatic deterioration at the end of the Pliocene seems to have been responsible for the decline and eventual disappearance of tapirs from Europe. A group of mammals that are not regarded as even slightly ‘European’ today were in fact a long-term, diverse component of European faunas for millions of years.

Lower right fourth premolar (at far left) and first three molars of T. balkanicus, from Spassov & Ginsburg (1999). The 'molarisation' of that premolar is really quite impressive. Scale bar = 1 cm.

Giant Asian tapirs. Several especially big tapirs are known from the Upper Miocene, Pliocene and Pleistocene of eastern Asia. The biggest of these were similar in size to mid-sized rhinos (we’re talking shoulder heights of 1.5 m, total lengths of 3.5 m or so) and have conventionally been given their own genus (Megatapirus). However, morphometric analysis of their teeth shows that they fall within the range of variation seen within Tapirus. Megatapirus is thus generally considered today to be a junior synonym (Dong 2005). I’ve written about Megatapirus here in the past: see the links below.

'Megatapirus' life reconstruction and fossil at London's Natural History Museum. Photo by Darren Naish. See link below for more info on this animal.

Tapirs of Los Angeles and elsewhere in North America. Tapirs are present in North America at various Miocene localities but are far better known from Pliocene and Pleistocene sediments. Indeed, tapirs were still present in the USA until close to the end of the Pleistocene, the California tapir T. californicus being known from the La Brea Tar Pits in Los Angeles. Several other extinct tapir species inhabited North America during the Pleistocene, including T. merriami in the west and south-west and T. veroensis and T. copei in the east.

South American tapirs were long assumed to have invaded the continent following the closure of the Panamanian Isthmus during the Late Pliocene. The presence of Upper Miocene tapirs in the Amazon Basin shows, however, that the group reached the continent somewhat earlier, perhaps by using the Baudo Pathway at about the same time as gomphotheres, dromomerycines, peccaries and others made the crossing as well (Prothero et al. 2014).

The so-called Baudo Pathway Hypothesis proposes that a terrestrial connection opened about 10 million years ago, connecting the Choco Terrane to Colombia and allowing animals to migrate north and south. Diagram from Prothero et al. (2014) and used with permission.

Invasion of the south… or invasion of the north from the south? Several Pleistocene fossil tapir species are known from Argentina, Brazil, Peru, Uruguay, Bolivia and Venezuela. Like fossil North American tapirs, these species fall predominantly into two main size classes: members of the larger size class (like T. tarijensis from Bolivia and T. oliverasi from Uruguay) would have been significantly larger than any living American tapirs and more similar in size to the Malayan tapir (Ferrero et al. 2014).

Whether the living species evolved within South America or originated elsewhere and then moved to South America is undetermined and a rather messy subject. The presence of various extinct species as far south as Argentina and Uruguay makes it look as if a lot of endemic tapir evolution occurred within the continent, and the fact that the Brazilian tapir is known as an Upper Pleistocene fossil in Argentina and Uruguay could be used to support the view that it (and other extant South American tapirs) originated deep in the south.

Maps showing distributional 'areas' of Pleistocene and living tapirs, from Holanda & Ferrero (2013). Note how southerly some of the Pleistocene species are.

However, phylogenetic analyses that incorporate modern and fossil tapirs find North American species (like the pygmy tapir T. polkensis) to be deeply nested within the ‘South American group’, as is Baird’s tapir T. bairdii (Holanda & Ferrero 2013). And Baird’s tapir is a pain: it has a range clearly centred on Central America and only inhabits the extreme north of South America. This is not what you’d predict for a species that originated in South America and has only recently moved north. Maybe tapirs actually invaded South America on several separate occasions, or maybe South America was a ‘species pump’ for the group that sent lineages north on several or many occasions. Either way, things are complicated.

Captive Baird's tapir - sometimes called the Central American tapir. Photo by Dave Hone, used with permission. UPDATE: nope on that ID! See comments.
Beautiful partial skull of T. polkensis from Gray Fossil Site, eastern Tennessee. Note the small size of this adult or subadult individual. From Hulbert et al. (2009).

American pygmies. At least some fossil American tapirs do not belong to either of those two main size classes I mentioned, since some were pygmies. T. polkensis from the Upper Miocene and Lower Pliocene of Florida and Tennessee is sometimes called the Pygmy tapir and would have been somewhat smaller than all extant tapirs except for T. kabomani. One site in Tennessee has yielded more than 70 specimens of T. polkensis, making it the richest tapir-bearing site in the world (Hulbert et al. 2009).

As should be obvious, there is tons to say on fossil tapirs, and I haven’t discussed half the things here that I wanted to. We’ll have to come back to fossil tapirs at some point. Until then, I hope you enjoyed this quick look at part of the rich fossil history of tapirs, and do enjoy and contribute to World Tapir Day 2016.

For previous Tet Zoo musings on tapirs, see...

Refs - -

Dong, H. 2005. Dental characters of the Quaternary tapirs in China, their significance in classification and phylogenetic assessment. Geobios 38, 139-150

Ferrero, B. S., Soibelzon, E., Holanda, E. C., Gasparini, G. M., Zurita, A. E. & Miño-Boilini, A. R. 2014. A taxonomic and biogeographic review of the fossil tapirs from Bolivia. Acta Palaeontologica Polonica 59, 505-516.

Holanda, E. C. & Ferrero, B. S. 2013. Reappraisal of the genus Tapirus (Perissodactyla, Tapiridae): systematics and phylogenetic affinities of the South American tapirs. Journal of Mammalian Evolution 20, 33-44.

Hulbert, R. C., Wallace, S. C., Klippel, W. E. & Parmalee, P. W. 2009. Cranial morphology and systematics of an extraordinary sample of the Late Neogene dwarf tapir, Tapirus polkensis (Olsen). Journal of Paleontology 83, 238-262.

Prothero, D. R., Campbell, K. E., Beatty, B. L. & Frailey, C. D. 2014. New late Miocene dromomerycine artiodactyl from the Amazon Basin: implications for interchange dynamics. Journal of Paleontology 88, 434-443.

Scherler, L., Becker, D. & Berger, J.-P. 2011. Tapiridae (Perissodactyla, Mammalia) of the Swiss Molasse Basin during the Oligocene-Miocene transition. Journal of Vertebrate Paleontology 31, 479-496.

Spassov, N. & Ginsburg, L. 1999. Tapirus balkanicus nov. sp., nouveau tapir (Perissodactyla, Mammalia) du Tirrolien de Bulgarie. Annales de Paléontologie 85, 265-276.

Van der Made, J. & Stefanovic, I. 2006. A small tapir from the Turolian of Kreka (Bosnia) and a discussion on the biogeography and stratigraphy of the Neogene tapirs. Neues Jahrbuch fur Geologie und Paläontologie, Abhandlungen 240, 207-240.