ALL OF THESE PROBOSCIDIANS AND THEN SOME FOUND IN ARIZONA
EARLIER CENOZOIC IN SOUTHERN ARIZONA

Cenozoic fossil-producing strata in Arizona range from the Oligocene to latest Pleistocene periods. While very late Wisconsin Ice Age deposits of 10,000 or less years are widespread, tantalizing accumulations of Miocene and Oligocene sediments with vertebrate fossils are being collected in lower beds exposed along the San Pedro Vally near the town of Mammoth and near Reddington Pass, just east of Tucson. Earlier deposits, from Paleocene on to the Miocene, have for the most part, been eroded down to harder, pre-Cenozoic pavements. Exciting finds of the bones of oredonts, primitive bear, titanothere bones and trackways of titanotheres have come to light in the past few years. These areas need extensive exploratio

THE SAN PEDRO FORMATION
The best and most complete series of mammal-producing beds in Arizona are usually considered to be the San Pedro deposits, exposed near the towns of Benson and Reddington. The San Pedro beds are composed of mostly unconsolidated marls (lumpy, nodule-rich carbonate lake deposits) and sands thought to be deposited over a rather short period of geologic time

Gone from the Pliocene deposits are the strange, unfamiliar creatures of earlier Cenozoic times, and found within the San Pedro beds are fossils of essentially modern, or at least more familiar families of mammals. Some 80 percent of the Pliocene mammals from Arizona are forms still living today.

THE PLEISTOCENE IN ARIZONA TIME OF THE WISCONSIN ICE AGE
It is quite impossible to predict (I say this a lot, don't I?) where new discoveries of Pleistocene or Ice Age vertebrate fossils might next be discovered. Usually found by accident, either by farmers plowing fields or by amateur naturalists roaming the hills in search of lesser treasures, the bones of a mammoth and mastodon (those most often found) are exciting to find, and can be found by anyone, almost anywhere in Arizona.
THE NACO, MURRAY SPRINGS AND LEHNER RANCH MAMMOTH KILL SITES IN SOUTHEASTERN ARIZONA

Ice Age sediments along the San Pedro River and other places in southeastern Arizona, older than 10,000 years, are world-famous for having evidence of humans hunting mammoth and other Late Pleistocene megafauna. The Pleistocene exposures in this area are vast and the potential for discovery of new kill sites is enormous. Each summer thunderstorm can send water cutting through the soft clay and silts on arroyo banks that will expose giant fossil bones and artifacts.

BLM information sign at the site of the Murray Springs Mammoth Kill Site
The Bison in Arizona

Generally, habitats in Arizona during the Late Pleistocene did not support huge herds of bison, but they did exist here and their fossils are occasionally found in both Ice Age deposits.

Skull of Bison bison from Santa Cruz County
After a particularly monstrous rainstorm and subsequent flooding of our road to the Sonorasaurs site in the foothills of the Whetstone Mountains, we blazed a safer shortcut across the desert and came across a prehistoric Indian butchering site covered with bison bones and stone tools.

My guess is that this archaeological site was less than 10,000 years old, as on skull parts, the fragile sheaths of horn were still intact, and in older deposits this does not happen in Arizona's climate.

One of several notable discoveries made in Arizona is associated with artifacts of man; the Naco site. About eight miles southeast of Bisbee and one mile northwest of Naco, Arizona, the Arizona State Museum undertook excavation of a mammoth skeleton in association with a large number of Clovis projectile points.
Clovis Culture Spear Points used to hunt the Imperial Mammoth in Arizona . These projectiles tipped the long shaft thrown with an Atl Atl, an Aztec word meaning spear thrower. The points are from about 2"-8" long, and as you see, were made of different materials(ASM)
A mammoth kill site exhibit at the Arizona-Sonora Desert Museum which I designed. The display contains bones and Paleo-Indian artifacts, but is really a composite of several southeastern kill sites.
From the fossil evidence provided by the bones, it appears that the Paleo-Indians separated young and females from the herd, cornered them in river-bends where the animals were dispatched with spears and rocks.
One agate spear point was removed from the base of the skull, one near the scapula, two from between ribs and one, which probably caused the animal's death, was found resting against an intravertibral surface, between the atlas and axis vertebra. This mammoth is the only specimen to the knowledge of this writer in which a fatal wound was evident from the archaeological remains. The spear point between the vertebra was a fortuitous shot for it no doubt severed the mammoth's spinal column, instantly killing the animal. Carbon-14 dates given to this even were reported to be about 11,000 years before the present. The deposits in which the bones were found were attributed to the action of streams and ponds which existed during a wet period just before the onset of arid conditions. There isn't a day that goes by when I'm in the middle of Arizona's Late Pleistocene exposures that I wonder when, and where I will come across a great mammoth that was killed, butchered, and eaten by one of the the great bands of hunters 10,000 years ago. Most such evidence is lost because Ice Age deposits are so fast, and bones and stone tools are easily washed away each time stormwater rushes through the normally dry arroyos and cuts deeply into the soft clay and sand which has held the relics for so many years.
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