The Indian Aurochs

The following is a near copy of a post which I had originally made on the now defunct CarnivoraForum, and then moved to Tapatalk. Now that I have my own blog, I've decided to move its here. Unfortunately, I've lost most of the references I used when drafting this post, and some of the pictures may not transfer properly; regardless, I think it will be a useful contribution to the discussion floating out there on this relatively obscure taxon. Without further ado:



Temporal Range: Middle Pleistocene to Holocene

Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Bovidae
Subfamily: Bovinae
Genus: Bos
Species: Bos primigenius
Subspecies: Bos primigenius namadicus

The Indian Aurochs, Bos namadicus, is an extinct species (or subspecies) of bovine in the genus Bos and is the wild ancestor of Zebu cattle. It previously ranged across the Indian subcontinent from Northern to Southern India and as far west as Eastern Iran, however it went extinct across its range during the Holocene.

Evolution
The Indian Aurochs is generally believed to be descended from either Bos planifrons or B.acutiforns, two possibly conspecific fossil bovines best known form deposits of Late Pliocene to Pleistocene age from the Siwalik hills of Pakistan and India. The Indian aurochs probably arose on the Indian subcontinent from one of these progenitors during the Middle Pleistocene. 

Taxonomy and Relationships
The Indian Aurochs is variably treated either as its own species with the binomial Bos namadicus, or as a subspecies Bos primigenius, which also includes the Eurasian Aurochs (B. p. primigenius) and the African aurochs (B. p. africanus). When treated as a subspecies the Indian Aurochs is classified trinomially as Bos primigenius namadicus; regardless of taxonomic arrangement "Indian Aurochs" is the colloquial name for the namadicus taxon. The Indian Aurochs was probably the first subspecies of the Aurochs to go extinct. 

Zebu cattle, the domestic descendants of the Indian Aurochs, are variably classified as either Bos indicusBos namadicus indicus or Bos primigenius indicus
Regardless of whether or not they are considered conspecific the Indian and Eurasian Aurochs were clearly closely related; this is evinced by the fact that their domestic descendants, zebuine and taurine cattle respectively, are completely inter-fertile (they readily hybridize and both male and female hybrid offspring are fertile)

Fossil record and AnatomyThe Indian aurochs is known from numerous fossil and sub-fossil remains, these remains are especially common on peninsular India. Unfortunately, remains of this species tend to be very fragmentary and only a few well preserved skulls and post-cranial elements are known. For this reason not as much is known with certainty of the anatomy and appearance of the Indian Aurochs as is known for the Eurasian Aurochs. Nevertheless, from what fossil material is known it is clear that, despite their high degree of similarity, the Indian and Eurasian Aurochs differed anatomically from each other in several characteristics, particularly with regards to the skull:

Skulls of Bos namadicus (left) and Bos primigenius primigenius (right)

The Horns
The horns of the Indian Aurochs are morphologically quite distinct from those of its Eurasian relative. The horn cores are more or less dorsoventrally compressed with an oval cross section as opposed to the circular cross section of Eurasian Aurochs horn cores; additionally, the horn cores of the Indian Aurochs often bear two well expressed keels, one dorsal and one ventral;these keels tend to be found on namadicus horn cores originating from Iran and are sometimes found on Indian horn cores as well. The horns of the Indian Aurochs adults are also proportionally much longer than those of adult Eurasian Aurochs, and they do not curve inwards as strongly; the horns also tend to extend further outwards in front of the face in namadicus than in primigenius

The Shape of the Skull
Few relatively complete skulls are known from namadicus, and for this reason it is difficult to obtain an accurate picture of the variation in particular skull characters in this species. However the skulls of namadicus generally appear to be somewhat narrow, especially as compared to primigenius skulls of similar sex and age. An additional difference between the two Aurochs forms is the morphology of the bones of the back of the skull: in namadicus the supracristal portion of the occiput overhangs the infracristal part, whereas in primigenius the occipital is always relatively flat. 

The Eye Sockets
The orbital rims of the the Indian aurochs were flat in both young and old animals. The eye-sockets may also have been less pronounced on average in the Indian Aurochs than in the Eurasian Aurochs 

In many of its skull features, namadicus is interestingly intermediate between Bos primigenius and the members of the subgenus Bibos (the Gaur, Banteng and Kouprey).

Post Cranial AnatomyThe post cranial anatomy of namadicus has not been well studied, possibly due to the lack of well preserved material. The exact size ranges of male and female Indian Aurochs adults are not known, however it is known that both bulls and cow of namadicus were smaller than the respective sexes of primigenius, and, though still large in comparison with most modern domestic cattle, namadicus appears to have been one of the smaller wild members of Bos. It is not possible to make reliable inferences regarding the anatomy of namadicus based solely on comparisons with the anatomy of Zebu. This is because Zebu, being derived domestic animals, have certainly undergone significant changes to their skeletal and soft-tissue morphology due to domestication. It may not be possible to know which anatomical features zebu inherited from their wild ancestor and which arose during the domestication process and were selected for by humans.

The Hump
It is not known whether or not the Indian Aurochs possessed the characteristic hump found nearly universally in its domestic descendants. Even if more post cranial material were available the presence or absence of the hump in namadicus may be difficult or impossible to ascertain on an osteological basis. This is because the hump is a soft tissue structure and thus does not fossilize, and no skeletal elements have been identified which necessarily indicate the presence of a hump in a living animal. It is known that zebu tend to have bifid thoracic vertebrae, however humped cattle without such vertebrae have been recorded, and there are even cases of humpless cattle with bifid vertebrae. Currently, there is no scholarly consensus on whether or not the Indian Aurochs was humped; some authors assert that the zebu hump must be a domestic characteristic selected for by humans while others suggest that the hump was a feature of namadicus which was merely inherited by zebu, possibly with later selection by humans for particular hump shapes. There are examples of petroglyphs from across India which show humped and humpless bovines in various contexts, including in what appear to be scenes depicting the hunting of wild cattle; however in the time period during which most or all of these petroglyphs were created there were a wide range of wild and domestic bovines present in South and Southwest Asia, so they do not unequivocally represent the Indian Aurochs.

Ecology
The Indian Aurochs was a xerophilic species and it is likely to have inhabited arid steppe and semi-desert environments across its range. Modern Zebu cattle possess many adaptations towards living in a hot, arid environment which are not found in taurine cattle, and these adaptations were most likely inherited from the Indian Aurochs; The fact that zebu have physiological traits which allow them to thrive in environments with high temperature and low humidity better than do taurine cattle has led to zebu being introduced in tropical and desertic regions worldwide.

If the Indian Aurochs was possessed of a hump, as are modern zebu cattle, then fat stores located inside this structure may have been used for energy in times of food shortage, the same purpose served by the humps of camels, which are adapted to similar environment. In this way the origin of hump could have been as an adaptation to the ecological niche of namadicus
The hump, if present, may have also played a role in sexual selection; males of most wild and feral bovine species engage in lateral displays where the size and strength of the forequarters is accentuated in order to intimidate rivals, sometime in lieu of actual sparring; structures such as the large shoulder humps of Bison and Yak and the high shoulder ridges of Gaur and Banteng serve to increase the apparent bulk of the forequarters for this purpose. A shoulder hump in namadicus may have aided males in putting on such lateral displays, though of course this is strictly speculative.

The Great Salt and Lut Deserts in Eastern Iran may have formed formed the western boundary of the range of the Indian Aurochs. The eastern boundary of it range has not yet been conclusively determined but there are not yet any records of Indian Aurochs fossils from East of the Indian subcontinent.

Relationship With Humans
The Indian Aurochs was an important game animal for early South Asian peoples; along with the Asian Elephant it constituted one of the main sources of animal flesh in the diets of paleolithic hunters in Central and Southern Peninsular India. It may also have been an object of worship, and may be one of the animals represented in the petroglyphs found at numerous Indian archaeological sites. 

Domestication and Extinction


Zebu and Sanga cattle are the modern domestic descendants of the extinct Indian Aurochs. Fossil and sub-fossil remains indicate that the Indian aurochs survived into the Holocene, and beginning around 8000 years ago in the Neolithic period it was domesticated into Zebu cattle, Bos Indicus. It is possible that that the first domestic namadicus aurochs were kept mostly for ritualistic purposes, only later being adopted for meat and milk production.

The center of domestication of the Indian Aurochs is usually placed in the Indus Valley area of Pakistan and North Western India, however there may have been at least one other ""recruitment center" were wild Indian Aurochs (typically females) were introgressed into the domestic population. Archaezoological and genetic evidence have confirmed the Indus valley as the first and primary center of domestication, however the precise location of the secondary recruitment center/s is uncertain. Southern India and the Gujarat and the Ganges floodplains have been proposed as possible locations based on genetic studies focused on mtDNA haplotype lineages in modern zebu populations. In any event, all populations of zebu cattle are typified by the presence of a hump composed of muscle and fat and variably positioned over the cervical and thoracic vertebrae. This hump is not found in taurine cattle, which were domesticated independently form the Eurasian Aurochs in the Near East

The earliest evidence of humped domestic cattle comes from Mehrgarh, a village site of Middle Pakistan dated to ca. 6000 BC. Shortly after this time the Indian Aurochs would have co-existed in the region with its early zebu descendants, as well as with imported taurine cattle. The domestication of Indian Aurochs in the Indus valley and subsequent spread of zebu across the surrounding region undoubtedly played a role in the development of pastorialism in South Asia. Zebu were eventually introduced to Africa, where they hybridized with local taurine breeds to produce Sanga cattle. Zebu were also transported around the Near East, reaching Mesopotamia, the Levant, and eventually Southern and Eastern Europe. 

However, while Zebu were spreading around the Old World from their centers of domestication, the wild Indian Aurochs underwent a gradual decline throughout its original range. Its exact date of extinction is uncertain, but is believed to have been around 2000 BCE, i.e. roughly 4000 years ago. The youngest known remains which clearly belong to wild Indian aurochs are from Banahalli in Karnataka, southern India, with an age of about 4200 years old. Hunting, habitat loss, as well as as a gradual increase in competition for grazing areas with domestic cattle all probably contributed to its decline; in all likelihood, these factors, along with hybridization with domestic cattle, eventually led to the extinction of the Indian Aurochs.

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