Extinct Ice Age Bison Scapula (shoulder blade)Late Pleistocene to Early Holocene Bison antiquus occidentalis This EXCELLENT Scapula (right) has a very beautiful patina. It has been stained in deep caramel brown colors by the peat/clay in which it lay for thousands of years. This specimen is in excellent condition , and belonged to an adult COW Bison antiquus occidentalis . The blade has a small chip at the proximal end (see pics) . Otherwise the condition of the bone is PERFECT. 15.4 inches long 8.1 inches wide These bones and teeth were unearthed by my wife and I from a peat bog in an urban development site in central Minnesota during the 80's and early 90's. We'd been searching the general area for fossil bison etc. since our first finds in 1972-73 along a small creek which flows near the site. Now the peat bog has been replaced by a series of drainage ponds serving the development. These specimens were legally obtained from private land. Along with the Bison remains from the Anoka sand plain site #1, we recovered a few scattered remains of quite a number of other types of animals, including; giant beaver ( Castoroides Ohioensis ), wolf ( Canis lupus ?subspecies ), eastern elk ( Cervus elaphus canadensis ), and others. Fish, mammals, reptiles, birds. Insects, mollusks, and of course, a lot of plant material. We also found man made artifacts and other evidence of human interaction with some of these bison. You can Google Earth the dig site at; 45*11'32.43"N 93*18'53.10"W if you want to get a sense of w on the Earth these creatures roamed, and what changes have been wrought to the land by both nature and man from then until now. Q- How do you know that these specimens are Bison antiquus occidentalis ? A- Good question. You can't tell to what Bison sub-species any particular tooth or bone belongs by just looking at it's features. As a matter of fact, except for the patina of age, bison teeth (and many of the bones) are virtually identical to the those of cattle (Bos). The answer is that these specimens have a certain provenance. All of these specimens came from a single discreet site. I have detailed bio-metric data (measurements) on a number of skulls from the same site. The indications are that most of the animals unearthed were of the sub-species occidentalis.
B. a. occidentalis has the most variable morphological characteristics of all bison species and sub-species. I have measured specimens that resemble B. bison, B. anitquus and B. priscus , and some that seem to stand on their own, LOL. I guess it depends upon wether you're a -lumper- or a -splitter-, taxonomically speaking. In my Notes this subject is discussed in greater detail.
B.a.occidentalis is generally thought to have arisen at the end of the pleistocene,appearing by about 15 thousand years ago, and co-existed allopatrically (more than one species living at the same time in different, although perhaps ajacent, areas) with B.a.antiquus untill about 5,000 B.P., when both species became extinct and were replaced by B.b.bison and B.b.athabascae , spanning the late pleistocene / holocene border in their mere ten thousand years of existance as a discreet sub-species.
Comparison of horn core characteristics is thought by many experts in the field to be the best method of differentiating between the various species and sub-species of bison. Each bison species has a unique, distinct set of horn core characters. These characters include; shape, size, orientation, texture, and canalization. The bio-measurement range for any particular species tends to overlap, at the extremes, into the ranges of other species. For example; According to J.N. McDonald, 1981, the spread of horn cores,tip to tip (chord), for B.a.antiquus ranges from 765 to 1067mm., while for B.a.occidentalis it ranges between 626 to 1055mm. Obviously, this measurement alone, while it is of great significance, is insufficient to determine to what species ...