Sivatherium

Sivatherium is an extinct genus of giraffid that ranged throughout Africa and Eurasia. The species Sivatherium giganteum is, by weight, one of the largest giraffids known, and also one of the largest ruminants of all time. Sivatherium originated during the Late Miocene in Africa and survived through to the late Early Pleistocene until around 1 million years ago.

Description

Sivatherium resembled the modern okapi, but was far larger, and more heavily built, being about tall at the shoulder, in total height with a weight up to. A newer estimate has come up with an estimated body mass of about or. This would make Sivatherium one of the largest known ruminants, rivalling the modern giraffe and the largest bovines. This weight estimate is thought to be an underestimate, as it does not take into account the large horns possessed by males of the species. Sivatherium had a wide, antler-like pair of ossicones on its head, and a second pair of ossicones above its eyes. Its shoulders were very powerful to support the neck muscles required to lift the heavy skull. Sivatherium was initially misidentified as an archaic link between modern ruminants and the now obsolete, polyphyletic "pachyderms". The confusion arose in part due to its graviportal morphology, which was unlike anything else studied at that time.

Palaeobiology

Palaeoecology

A dental wear analysis of S. hendeyi from the Early Pliocene of South Africa found that the teeth were brachyodont, but had a higher hypsodonty than a giraffe, and that it was best classified as a mixed feeder, being able to both graze and browse. Analysis of dental microwear and mesowear paired with δ¹³C and δ¹⁸O measurements of S. maurusium from Ahl al Oughlam in western Morocco show it predominantly fed on C₃ vegetation.

Palaeopathology

The osteohistology of S. hendeyi specimens from the Langebaanweg site in South Africa shows numerous interruptions in growth related to extended, non-cyclical stress events likely related to drought, fire, or flooding that decreased food availability.

Relationship with humans

Remains of Sivatherium from Olduvai Gorge in Tanzania, dating to around 1.35 million years ago have been found associated with stone tools and bearing cut marks, indicating butchery by archaic humans, likely Homo erectus. Historically, it has been suggested that figurines from Sumer and ancient rock paintings in the Sahara and Central West India represent Sivatherium. However, these claims are not substantiated by fossil evidence, and the depictions likely represent other animals.