Ostriches (Struthios sp.) Occurred in India during the Late Pleistocene

The ratites are ground dwelling birds that originated on the supercontinent of Gondwanaland before it split apart.  The ratites include the kiwi bird of New Zealand, the cassowary of New Guinea and northern Australia, the emu of Australia, the rhea of South America, penguins of Antarctica, and the ostrich of Africa.  About 10 million years ago, Africa collided with Eurasia, allowing ostriches to expand their range north.  The fossil record suggests ostriches occurred on the Himalayan Highlands from the Miocene until the mid-Pleistocene.  During the late Pleistocene ostriches shifted their range south and lived in western and central India.  Ostriches disappeared from India about 10,000 years ago and are now confined to Africa.

Ostrich

Ostriches belong to the ratite family along with emus and cassowaries.  They evolved on Gondwanaland before Australia, Africa, Antarctica, and South America broke apart.  Ostriches colonized Asia and occurred in India during the late Pleistocene but became extinct there about 10,000 years ago.

Pike Place Market Creamery - Seattle, WA, United States. Ostrich egg compared to chicken egg

Ostrich egg compared to chicken egg.  Ostrich egg shell fragments dating to the Pleistocene are more common in India than the actual ostrich bones.

Ostriches prefer a type of habitat known as the Sahel.  Sahel vegetation grows on semi-arid tropical steppe and consists of grassland and savannah with some woodland and shrub land.  A latitudinal band of Sahel vegetation currently exists between the Sahara desert and the Sudanese savannah.  The presence of ostriches in the Asian fossil record suggests Sahel-like vegetation existed in the Himalayan Highlands for millions of years.  Sahel-like landscapes predominated in central and western India from over 60,000 years ago to ~10,000 BP. Habitat on the Himalayan Highlands may have deteriorated into pure desert during severe glacial episodes, and ostriches used the Indus River corridor as a route to central India.  Ostriches and humans (Homo sapiens) were the only new large vertebrates to colonize this region during the late Pleistocene.  Most anthropologists believe humans first colonized India by following a coastal route, but people may have used the Indus River corridor to colonize India from the Himalayan Highlands instead.

Sahel Beautiful Landscapes of Sahel

Photo of Sahel-vegetation, the favored habitat of the ostrich.  The Sahel belt is a zone between the Sahara desert and the Sudanian savannah.  Habitat like this was common in India during the late Pleistocene.

Other species of large vertebrates that prefer Sahel-like vegetation still occur in India.  Lions, wild asses, and rhinos still find suitable habitat in India but it occurs in patches.  The shift from glacial to interglacial vegetation patterns may not explain the disappearance of ostriches from India because grasslands and savannah still exist there.  Humans may have overexploited ostriches.  Archaeologists have found beads made with ostrich eggshells and ancient rock paintings of the big birds in India.

India did not suffer a major extinction event at the end of the Pleistocene.  A study of 21 Pleistocene mammals determined just 1 species, a baboon, became extinct then.  Baboons are highly adaptable apes that directly compete with humans for the same resources.  I believe humans are behind the extirpation of baboons and ostriches from India.  Tropical diseases kept human populations low, however, and other species of megafauna were able to survive human impacts.  Later, the Hindu prohibition against killing became popular, helping to protect animal populations.  The Hindu religion may be as old as 7000 years, beginning at a time when India was still a vast wilderness.

Scientists can’t determine what species of ostrich lived in Pleistocene India.  It may have been a unique species or the same still extant in Africa.   Ostrich egg shell fragments are far more common at fossil sites than the actual ostrich bones.

Reference:

Blinhorn, James; Hema Achyuthan, and Michael Petragla

“Ostrich Expansion into India during the Late Pleistocene: Implications for Continental Dispersal Corridors”

Palaeogeography, Palaeoclimatology, Palaoecology 2015

https://www.academia.edu/8976173/Ostrich_expansion_into_India_during_the_Late_Pleistocene_Implications_for_continental_dispersal_corridors

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