Eurybelodon shoshanii: a new Unusual Shovel-tusked Gomphothere From Miocene Neogene Oregon

Eurybelodon shoshanii, an unusual new shovel-tusked gomphothere (Mammalia, Proboscidea) from the late Miocene of Oregon

Author:

Lambert

Abstract:

Unusual shovel-tusked gomphothere material from the late Clarendonian Black Butte Local Fauna (Juntura Formation, Oregon), including a lower tusk, partial upper tusk, and two mandibles including a second and a third molar, has been described and referred to Platybelodon. Platybelodon has the following diagnostic characteristics: molars strongly double-trefoiled; third molar with five lophs; lower tusks short with broad and very flat profiles lacking significant dorsoventral curvature; and lower tusks lacking obvious lamination but instead filled with small, short dentinal rods. However, the Black Butte shovel-tusked gomphothere was referred to Platybelodon despite having the following conflicting features: molars with weakly developed single trefoiling; third molar with only four lophids (the fourth little more than a talonid); broad, moderately flattened, relatively elongated lower tusk with strong dorsal curvature; and lower tusk internal structure showing lamination rather than dentinal rods. In addition, both the upper and lower tusks of the Black Butte shovel-tusker have prominently corrugated enamel cortices, a feature unknown in any other gomphothere. Thus, given the lack of a single clear-cut shared diagnostic feature and the large number of differences between these taxa, the identification of the Black Butte shovel-tusker as Platybelodon must be refuted. Refutation of the Platybelodon identification requires an alternate identification to be made for the Black Butte shovel-tusker. No other known shovel-tusker genus, including the genera Amebelodon, Serbelodon, and Torynobelodon, possesses the unusual combination of tusk and cheek tooth features observed in this animal. Accordingly, it is here referred to a new genus and species, Eurybelodon shoshanii.

15 Sites are Considered Undisputed Examples of Clovis Era Human Predation of Megafauna

Revisiting Paleoindian Exploitation of Extinct North American Mammals

Authors:

Grayson et al

Abstract:

In 2002, we assessed all sites known to us that had been suggested to provide evidence for the association of Clovis-era archaeological material with the remains of extinct Pleistocene mammals in North America. We concluded that, of the 76 sites we assessed, 14 provided compelling evidence for human involvement in the death and/or dismemberment of such mammals. Of these sites, 12 involved mammoth (Mammuthus), the remaining two mastodon (Mammut). Here, we update that assessment. We examine Clovis-era, and earlier, sites reported since 2002, as well as sites examined previously but for which additional information has become available. Our assessment leads us to exclude Hebior (Wisconsin) from the list of accepted sites, and to add El Fin del Mundo (Sonora) and Wally’s Beach (Alberta). There are now 15 sites on our list, providing what we find to be compelling evidence for human involvement in the death and/or dismemberment of five genera of now-extinct late Pleistocene mammals: Equus, Camelops, Cuvieronius, Mammut, and Mammuthus. As in 2002, however, we note this is a small fraction of the 37 genera that disappeared at the end of the Pleistocene, and for this and other reasons we remain highly skeptical that human overkill was responsible for their extinction.

Did Clovis Culture Originate in Central or South America?

Of the scores of North American archaeological sites claimed to provide evidence of human hunting of now-extinct Pleistocene mammals, only about a dozen have compelling evidence of such predation. In all instances, the animals involved were mammoth and mastodon (1). In PNAS, Sanchez et al. (2) contend that a third genus of proboscidean (elephants and their near relatives), the gomphothere Cuvieronius, should be added to the small list of large mammals pursued by Clovis hunters. It is an intriguing claim; skeptics, however, might require more proof than is currently available.

link.

Youngest Gomphothere Site in Mexico (13.4kya) has Clovis Points (yup, they get et too)

An animal once believed to have disappeared from North America before humans ever arrived there might actually have roamed the continent longer than previously thought – and it was likely on the list of prey for some of continent's earliest humans, researchers from the University of Arizona and elsewhere have found.

Archaeologists have discovered artifacts of the prehistoric Clovis culture mingled with the bones of two gomphotheres – an ancient ancestor of the elephant – at an archaeological site in northwestern Mexico.

The discovery suggests that the Clovis – the earliest widespread group of hunter-gatherers to inhabit North America – likely hunted and ate gomphotheres. The members of the Clovis culture were already well-known as hunters of the gomphotheres' cousins, mammoths and mastodons.

Although humans were known to have hunted gomphotheres in Central America and South America, this is the first time a human-gomphothere connection has been made in North America, says archaeologist Vance Holliday, who co-authored a new paper on the findings, published this week in Proceedings of the National Academy of Sciences.

"This is the first archaeological gomphothere found in North America, and it's the only one known," said Holliday, a professor of anthropology and geology at the UA.

Holliday and colleagues from the U.S. and Mexico began excavating the skeletal remains of two juvenile gomphotheres in 2007 after ranchers alerted them that the bones had been found in northwestern Sonora, Mexico.

They didn't know at first what kind of animal they were dealing with.

"At first, just based on the size of the bone, we thought maybe it was a bison, because the extinct bison were a little bigger than our modern bison," Holliday said.

Then, in 2008, they discovered a jawbone with teeth, buried upside down in the dirt.

"We finally found the mandible, and that's what told the tale," Holliday said.

Gomphotheres were smaller than mammoths – about the same size as modern elephants. They once were widespread in North America, but until now they seemed to have disappeared from the continent's fossil record long before humans arrived in North America, which happened some 13,000 to 13,500 years ago, during the late Ice Age.

However, the bones that Holliday and his colleagues uncovered date back 13,400 years, making them the last known gomphotheres in North America.

The gomphothere remains weren't all Holliday and his colleagues unearthed at the site, which they dubbed El Fin del Mundo – Spanish for The End of the World – because of its remote location.

As their excavation of the bones progressed, they also uncovered numerous Clovis artifacts, including signature Clovis projectile points, or spear tips, as well as cutting tools and flint flakes from stone tool-making. The Clovis culture is so named for its distinctive stone tools, first discovered by archaeologists near Clovis, New Mexico, in the 1930s.

link.

And, yes, I guess it did hold up.

paper link when I see it.