I recently obtained a book on North American mammal taxonomy from 1902. The list of North American mammal species they list is very different compared to today's list - a lot's been lumped since then! This book recognizes no less than 34 ungulate species in North America (which includes what is now the US, Canada and Greenland) - many of these with multiple subspecies! Here's the list, I thought it would be interesting to show how ungulate taxonomy has changed over the last 120 years:
Texas Peccary Tayassu angulatum
American Elk Cervus canadensis
Roosevelt's Elk Cervus occidentalis
Merriam's Elk Cervus merriami
Virginia Deer Odocoileus virginianus
Florida Deer Odocoileus osceola
Texan or Fan-tailed Deer Odocoileus texensis
Arizona Deer Odocoileus couesi
White-tailed Deer Odocoileus leucurus
Mule Deer Odocoileus hemionus
Cerros Island Deer Odocoileus cerrosensis
Crook's Deer Odocoileus crooki
Columbian Black-tailed Deer Odocoileus columbianus
Moose Alces americanus
Alaskan Moose Alces gigas
Woodland Caribou Rangifer caribou
Mountain Caribou Rangifer montanus
Stone's Caribou Rangifer stonei
Newfoundland Caribou Rangifer terrae-novae
Barren Ground Caribou Rangifer arcticus
Greenland Caribou Rangifer graenlandicus
Grant's Caribou Rangifer granti
Pronghorn Antilocapra americana
Mountain Goat Oreamnos montanus
Kennedy's Mountain Goat Oreamnos kennedyi
Mountain Sheep Ovis cervina
Nelson's Sheep Ovis nelsoni
Mexican Sheep Ovis mexicanus
Stone's Sheep Ovis stonei
Dall's Sheep Ovis dalli
Fannin's Sheep Ovis fannini
Musk Ox Ovibos moschatus
Peary's Musk Ox Ovibos wardi
American Buffalo Bison bison
One of the stranger things that stood out to me is that they can split 7 species just in North American, yet recognize no Pronghorn subspecies.
Wow! Thank you for sharing this with us. Taxonomy really has changed. For example, the Rocky mountain goat (Oreamnos americanus) is considered a monotypic species. There was a paper on the taxonomy of Rocky mountain goats written in the 1960s. Dr. James Dolan, the former General Curator of the Zoological Society of San Diego was one of the co-authors, and he said that though the conclusion is that Oreamnos americanus turned out to be monotypic, if any subspecies were to be valid/distinct ssp. kennedyi would be the one that warrants distinction. If I come across the paper again, I'll post it here.
Another example for Bighorn sheep, ssp. mexicanus and ssp. nelsoni are now considered synonymous.
For the reindeer, I don't believe ssp. arcticus is still valid, and ssp. terrae-novae is now considered synonymous with ssp. caribou