Pandas: a Major Problem for Evolution
The giant panda, one of the most popular and lovable zoo animals, is in the top ten of animal favourites. Called a super large teddy-bear, the panda has appeared as toys and dolls, on calendars, and thousands of other items. Reasons why it is so popular include its cute baby bear face, its cuddly soft roundness, and its clumsy playfulness. It was called a white bear for years because it has black fur on its legs, ears and around its eyes on an otherwise white body.
Pandas consume about 18 kg (40 pounds) of bamboo a day. Bamboo makes up 99% of their diet but they will occasionally eat meat. Their major enemy is humans, though occasionally snow leopards or wild dogs have been known to eat cubs who have wandered from their mom. Humans have hunted them for their fur and encroached onto their land for decades. Only about 1,000 were left until, in recent years, a systematic effort was made to prevent their extinction due to their popularity and worldwide concern for their fate.
Two main pandas exist, the familiar giant panda ( Ailuropoda melanoleuca) weighing up to 160 kg and the 3 to 4.5 kg red panda (Ailurus fulgens). The giant panda is an enigma to evolutionists because no one has proffered even close to a reasonable idea of what animal it could have evolved from. Indeed, pandas are so different from all other animals that evolutionists have had a hard time even postulating a logical evolutionary origin scenario. One scientist, after studying the panda for many years, concluded that the giant panda evolved from the bear family and the red panda from the raccoon family. Other biologists “looked at the same evidence and came away convinced that the two were relatives, belonging to the same branch on the evolutionary tree” (George Schaller. 1993. The Last Panda. University of Chicago Press p. 261).
Evolutionists assume that, because humans appear to have shared certain features in common with apes and gorillas, this is evidence that they have descended from a common ancestor. In contrast, many animals often have similar features, yet evolutionists do not believe they could be derived from a common ancestor. An example of two animals with some similar features, yet which are different enough that evolutionists do not believe they could be derived from a common ancestor, is the case of the giant and red pandas. They differ in that the giant panda looks much like a medium sized bear. The red panda looks like a red raccoon and is about the same size, has a long striped tail, but it also has a bear like face, and other bear like features (Ramona and Desmond Morris. 1966. Men and Pandas, McGraw-Hill pp. 18-19).
The red and giant pandas also share many traits. Both have enlarged sesamoid [a bone developing within a tendon] thumbs (or slightly enlarged carpal/wrist bones) that in the case of the giant panda, function as opposable thumbs to help them grip bamboo so as to strip off its leaves, their main diet (Michael Salesa. 2006. Proceedings of the National Academy of Sciences 103 (2): p. 397). This feature is one reason why they are both labeled pandas. Nevertheless evolutionists do not believe these animals have a close evolutionary relationship because of the many major differences between them.
The skull, teeth and forepaws of both the red and giant pandas are all designed to help them consume bamboo, but only the giant panda can use its radial sesamoid as an opposable thumb (Schaller p. 261). Though the red panda’s radial sesamoid is not as pronounced as that of the giant panda, recent research suggests that the red panda can use them like an opposable thumb, but in a very different way than that of the giant panda (Hideki Endo et al. 2005. Annals of Anatomy 183 (2): 181-184.) The problem is, although they “are not closely related, their sharing of this adaptation implies a remarkable convergence” (Salesa p. 397). The “independent evolution” of both pandas is very difficult to explain and document.
The panda was historically considered as just another type of bear because its external appearance is superficially very similar to a bear (Morris and Morris p. 183). Schaller wrote: “Is the giant panda a bear? Are the red and giant pandas closely related? These two questions have been debated for over a century. Anatomists, behaviorists, paleontologists, and molecular biologists have led the fascinating inquiry into the evolutionary relationships of these species with ingenuity and persistence, yet they continue to derive different conclusions on the basis of different evidence, and they still pursue the elusive answers.” (Schaller 1993 p. 261).
The raccoon school concluded that the giant panda and the red panda both evolved from the raccoon family Procyonidae, and the bear school concludes that they both evolved from a true bear and are members of the family Ursidae (Morris and Morris p. 182). For several decades researchers have moved back and forth between these two views. Professor Peacock’s solution to their evolution was to put the giant panda in the bear family, and the red panda in the raccoon family. (Dr. Peacock is a polar bear and panda biologist working for the Canadian Government.) This view caught on, but much controversy still exists. The giant panda is now believed to have descended from bears and the red panda from the raccoon, which is currently placed in its own family, the Ailuridae.
Researchers from the US National Cancer Institute and the National Zoo analyzed genes and proteins from pandas, raccoons, and bears. They concluded that the red panda is not as closely related to the raccoon as it looks, but the giant panda is closer to a bear than most biologists thought (Hammond, 1985).
Yet enormous differences exist between a giant panda and bears. No evidence exists that either the red or the giant panda can hybridize with any bear species. Bears walk flat on their hind feet, pandas walk on their hind feet toes. Bears have long claws useful for digging, while pandas have a modified sesamoid bone that functions as a thumb. Most bear species have 74 chromosomes, pandas only 42. The panda’s digestive system is much shorter than that of bears, so short it can digest only about 20% of its food compared to 60% for most herbivores. To obtain sufficient calories it must consume 12 to 15% of its body weight in food daily, requiring it to eat for 15 hours each day of its adult life.
An excellent panda fossil record exists over a wide area, from Burma to Szechuan China. So far, no fossils have been located that link the panda to any theoretical evolutionary ancestors. The earliest known panda fossils (Pleistocene), appear to be fully modern pandas. Some argue that the reason little change is seen in the fossil record is because the only very early evidence of pandas so far includes isolated teeth, lower jaws, and a few skulls (C. Jin et al. 2007. Proceedings of the National Academy of Sciences 103 (2): p. 10932). Only an extinct, supposedly the “pygmy” version of the giant panda known as Ailuropoda microta, has ever been found in the fossil record.
This evidence, though, is enough for zoologists to conclude that the panda “has not changed its appearance since the Pleistocene” (I. Poglayen-Neuwall 1975. Grzimek’s Animal Life Encyclopedia. Van Nostrand Reinhold vol. 12 p.112). The major difference is fossils of the earliest giant pandas discovered indicate that it was about half the size of the modern giant pandas. Their feeding behaviour, though, judging by the skull and teeth, was centered on bamboo as is true today. There is not much to cheer about when it comes to ideas about panda evolution, is there?
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