Posts Tagged ‘Platygonnus’

The Adaptability of Pleistocene Peccaries

June 30, 2018

Two lineages of peccaries lived all across North America for over 5 million years but both became extinct about the time man appears in the archaeological record.  The long-nosed peccaries in the Mylohyus genus were forest edge species, and the flat-headed peccaries in the Protherohyus-Platygonnus genuses inhabited scrubby thickets.  A new study looked at dental microwear and bone chemistry in these lineages and compared them with the teeth and bone chemistry of the extant white-lipped peccary to determine the dietary similarities and differences of the extinct and extant species of peccary.  Peccaries in the Mylohyus genus co-existed with Protherohyus peccaries during the Miocene over 5 million years ago.  The former ate more woody browse and forest vegetation, while the latter mostly ate grass.  During the Pliocene between 5 million years BP-2million years BP both Mylohyus and Platygonnus ate mostly woody browse in Florida.  Their diets shifted during the early-mid Pleistocene with an increased consumption of grass.  During the late Pleistocene Mylohyus ate more forest vegetation such as twigs, acorns, and nuts, while Platygonnus ate more tough leaves and grass.  This study shows how adaptable these lineages were to environmental change–their diets shifted with changes in climate.  It seems obvious to me that overhunting and/or disruption of the overall ecosystem by humans, not whole scale environmental change, caused the extinctions of both Mylohyus and Platygonnus.  Surviving extant species of peccaries live in deserts and remote jungles where human populations remain sparse.

Image result for mylohyus nasutus

Image result for Platygonus compressus

Illustration of Platygonnus peccary.

Image result for white-lipped peccary

White-lipped peccaries eat forest vegetation.  They can be dangerous.

The proliferation of feral pigs (Sus scrofa) in North America today demonstrates how favorable the environment still would be for Pleistocene peccaries, if they still existed.  Pigs co-evolved with humans in Eurasia to produce large litters, making them capable of surviving human hunting pressure.  Pigs produce litters of 8-12, but peccaries only birth 2-4 young.

Some archaeologists reject the likelihood that humans hunted peccaries to extinction because there are no known kill sites, other than a peccary shoulder blade with a spear hole in it next to a spear.  See: https://markgelbart.wordpress.com/2014/03/10/the-sheridan-cave-pit-fossil-site-in-wyandot-county-ohio/

This is a ridiculous assumption. There are also no known white-tailed deer kill sites in the archaeological record, but we know Indians hunted deer.  Evidence humans killed Pleistocene peccaries simply faded away over time.

Reference:

Bradham, J. et. al.

“Dietary Variability of Extinct Tayassuids and Modern White-Lipped Peccaries (Tayassu pecari) as Informed from Dental Microwear and Stable Isotope Analysis”

Palaeogeography, Palaeoclimatology, Palaeoecology April 2018