Cheetahs, Then and Now
Most people who can actually identify a cheetah will be able to tell you that cheetahs live on the plains of sub-Saharan Africa. A smaller number of people will know about the history of cheetahs in India and the Middle East. Fewer still will know that cheetahs and cheetah-like fossils have turned up in some fairly unexpected places - not just Africa, India, and the Middle East, but China, Europe and North America as well.
Made in the USA
North American has hosted at least two cheetah-like cats – Miracinonyx inexpectatus and Miracinonyx trumani. The rumor mill tells of a third lesser known cat called Miracinonyx studeri which lived in North America at the same time as Truman, but details are thin. Adding to the confusion, some literature refers to these cats as Acinonyx rather than Miracinonyx.
The main features that make these cats similar to the cheetah are the long slender limbs, a proportionally smaller head, and reduced canines. The entire catalog of similarities and differences between these extinct cats and the cheetah is so detailed that only a paleontologist could truly appreciate them. Although the skeletons of these cats resemble modern cheetahs, there are significant differences as well, and we don’t even know what the cats looked like, such as coat color and spot pattern, or if they even had spots at all. Roughly speaking, the skeletal structure of Inexpectatus most closely resembled that of the modern puma, and Trumani had more in common with the modern cheetah.
Inexpectatus is much older, with fossils dating back to over two million years ago. Inexpectatus shared its timespan with jaguars and with the saber-toothed cat Smilodon. Speculators suggest that these three cats could have co-existed in a way similar to what the cheetah, leopard, and lion do in Africa today.
Trumani is recent history by comparison, dating back to as late as only twenty thousand years ago. Trumani has no known overlap in time with the larger and older Inexpectatus. DNA tests have shown that Trumani is related to the modern puma. DNA tests have also shown that the cheetah is related to the puma, so this means that Trumani is at least distantly related to the modern cheetah.
Looking farther back, Inexpectatus and Acinonyx pardinensis (the European giant cheetah) existed at about the same time and might have had a common ancestor, but they are different enough that they are not the same species of cat. The North American variety is the more primitive and less specialized of the two.
Being more primitive, Inexpectatus could be the ancestor of the European cheetah, which would be possible if it migrated to Eurasia during the ice age. Inexpectatus might also have been the ancestor for Trumani and the puma. Or on the other hand, its extinction might have cleared the way for these other cats to move in from elsewhere.
It's possible that the American and European cats developed their cheetah-like features separately in order to fill a similar niche on two different continents. However, since Trumani, the puma, and the cheetah are related, if Inexpectatus isn't the common ancestor, then there would still have to be another as yet undiscovered common ancestor that migrated one way or the other.
European Born and Bred
The cheetahs from North America were not quite like our modern cheetahs, but fossils found in Europe from the same time period as Inexpectatus are closely related to extant cheetahs. The oldest known Eurasian cheetah fossil is from France, from the Late Pliocene period (over two million years ago). The bones are the remains of the giant cheetah, Acinonyx pardinensis.
The giant cheetah was as tall as a modern lion, but not nearly as bulky as a lion. This cat was obviously larger than the cheetah known to Africa, but other than that they are very similar. Pardinensis roamed parts of Europe, China, and India. Slightly later in time we see another variety called Acinonyx intermedius, which was smaller than the giant cheetah, but still larger than the African cheetah.
All three of these cats could have actually been the same species, with the Eurasian variety being bigger due to the colder climate. Smaller cheetah fossils found in southern and eastern Africa date back to nearly the same time period. This situation could be similar to the tiger today, where we find a variety of tiger subspecies that vary significantly in size and coat type.
How Many Cheetahs Does It Take
A commonly quoted statistic says that there were 100,000 wild cheetahs at the turn of the century (the early 1900s). This number was obviously estimated well after the fact. Unfortunately, even though the number is often repeated, the methods for determining the number are not. It has become almost folk lore.
More recent estimates from the 1990s put the total population down to 12,000 cheetahs left in the wild, mostly in sub-Saharan Africa. Up to 2500 of those live in Namibia, with other somewhat smaller groups in Botswana, and Zimbabwe, and even smaller numbers in the surrounding areas, mostly in the east. Historically cheetahs have been known to thrive in almost any arid environment with the exception of thickly forested areas and wide expanses of sand.
Optimistically (very optimistically), there might be a few hundred cheetahs left in the north, spread from Iran to the southwestern Sahara - these are the remnants of the Asiatic cheetah. The Asiatic cheetah population size is decreasing and could soon quietly disappear into extinction. Their historic range covered northern Africa and southwestern Asia. There are no known wild cheetahs left in Israel, India, or anywhere else in Asia or Europe.
Local studies have indicated that in at least some areas of Africa, the cheetah population appears to be stable, meaning that the numbers are not going down and the occupied range is not getting smaller. However, on a global scale the total cheetah population is decreasing.
Researchers compile cheetah population estimates primarily through interviews with local people, and through their own personal observations. Taking a census through interviews is problematic because human recall of past events is quite fallible, depending on how long ago the sightings took place and even how well the person can identify a cheetah. With this method there is also no way to know if the same cat has been counted multiple times, or how many haven't been counted at all.
Taking a census through research observations is also risky because the research team is bound to cover a limited area, whereas the cats are free to come and go. Cats that leave the census area could then be counted again in the census of another area later on. Although researchers take precautions to identify individual cats during this type of census, they are still trying to count, metaphorically speaking, needles in a haystack. From this perspective it appears that cheetah conservation is running blind because many critical long-term decisions depend on these numbers.
Go Forth and Prosper
Cheetahs are infamous for their lack of genetic diversity, meaning that they are all closely related to each other. The consequences of this condition have been heavily debated, but the cause at least seems to be known. Cheetahs experienced a population bottleneck, meaning that their total breeding population dropped dramatically, possibly as low as 500 cats. Climate changes are the most widely accepted cause of the bottleneck, which occurred near the end of the last ice age over 10,000 years ago. Cheetahs were not the only victims and were actually quite fortunate. Many animal species from the same period went extinct in a relatively short time span.
Despite this near disaster, cheetahs recovered and even thrived. Although cheetahs still have limited genetic diversity, the loss in population size today has nothing to do with that. Without a doubt, their imminent threat of extinction is due to our direct interference. People hunt cheetahs as pests and as trophies, decimate their food supply to support livestock, and convert their habitat to farmland. People are the reason that cheetah numbers are falling today.
Cheetahs have large territories and are mostly solitary, so cheetah populations are sparse. These populations are extremely vulnerable because they depend on the ability to mingle with neighboring populations. As humans spread out, open areas become fragmented, and cheetah populations that could previously interbreed become isolated and die out. The only way to avoid this, assuming that people will continue to expand no matter what, is for cheetahs and people to live on the same land. Our awful history with the cheetah begs the question - is this even possible?
To be continued...