Cave Bear, Ursus spelaeus

The cave bear (Ursus spelaeus) is an extinct species that was found in Europe during the Pleistocene. Its range was large and included areas from Great Britain to Spain, Italy, Poland, the Balkans, areas of Germany, Russia, the Caucuses, Romania, and northern areas of Iran. Large numbers of skeletons have been found in Switzerland, southern Germany, Austria, northern Spain, Hungary, Croatia, and Romania. Because so many fossils have been found throughout Europe, some experts assert that there must have been “herds” of cave bears when the species lived, while others assert that the large number of fossils merely accumulated over the years in the caves. This species would have preferred a habitat within mountainous or forested regions, especially those with abundant limestone caves, and would most likely have avoided open areas like plains.

Johann Friederich Esper first described the cave bear in 1774 in his book Newly Discovered Zoolites of Unknown Four Footed Animals. This species was once thought to be a number of creatures including apes, unicorns, dragons, dogs, and cats, but Esper asserted that it was most likely related to polar bears. Twenty years after its initial description, the cave bear was given its scientific name, which is similar in meaning to its common name.

The cave bear varied in weight, with males weighing between 880 and 1,102 pounds and females reaching an average weight of up to 551 pounds. The majority of skeletons of this species that have been placed in museums are males, because it was thought that female skeletons were dwarfs and could not represent the species properly. This species has a broad skull, which is domed at the top but flattens out at the forehead.

It is thought that the cave bear, along with the brown bear, is descended from the Plio-Pleistocene Etruscan bear (Ursus etruscus), which probably went extinct around ten thousand years ago. Deninger’s bear is thought to be transition species between Ursus etruscus and the cave bear, although some experts assert that Deninger’s bear is a variation of the cave bear or a subspecies. Scientists have studied the progression of the cave bear by looking at the premolars, which, over time, were reduced in size or completely disappeared. Genetic studies have also been conducted in California, also using the premolars, and these studies have shown the possible divergence of the cave bear lineage from the brown bear.

The diet of the cave bear is thought to have contained tough plant materials, because of the wear on the teeth studied. However, it has not been found to eat the same foods as brown bears, like tubers, which can cause a large amount of damage to teeth over time. Scientists have concluded that the cave bear must have consumed large amounts of plant materials. This is supported by studies conducted on bones, which have revealed that bone isotopes contain the correct amount of nitrogen for an herbivore. There is evidence that suggests the cave bear may have eaten small amounts of meat. The teeth of this species show damage that is similar to that in Eurasian brown bears, although the cave bear would have eaten more bones than this modern relative. It is thought that the cave may have scavenged on other caves bears that died during hibernation. Individuals found in Peştera cu Oasein in the Carpathian Mountains showed evidence of having an omnivorous diet, based on studied conducted on the nitrogen levels found in the isotope of their bones. Despite the diet of these individuals, and bears found in other regions, it is widely thought that the cave bear had an herbivorous diet.

When the cave bear lived, it would have perished due to a number of causes, most commonly death during hibernation. This is a cause of death in many bear species today and occurs when bears do not eat enough food to fatten up before winter. Studies have shown that these bears could have suffered from a large amount of ailments including bone tumors, tooth resorption, kidney stones, and periostitis. Many male skeletons have been found to have broken bacula, most likely caused by fights during the breeding season. The cave bear did not fall victim to larger predators, but could have been hunted by pack animals like hyenas or wolves, which most often killed young or sick individuals. In some caves, the skeletons of cave lions have been found alongside those of cave bears, showing a rare tendency of the lion to kill the bear while it was hibernating. This would sometimes end in death for the lion, resulting in the bones being found together.

By studying the bones of cave bears in their natural location, scientists have found that Neanderthals may have worshiped the bears. In one location, known as Drachenloch, a chest was found with several cave bear bones on its top, and many other bones, including skulls, were found throughout the cave. This site contained a number of bones from other bear species, and has been noted as where the “Cult of the Cave Bear” was found. Another site, located in Regourdou in southern France, contained the bones of at least twenty bears as well as the bones of a human and a variety of man made objects. Like Drachenloch, a large slab of stone covered this site. One site from Savona, Italy, known as Basua Cave, holds a stalagmite that resembles an animal, and many bear bones as well as clay pellets were found surrounding the natural structure. This site suggested a ritual purpose, although in a different manner than the others, but none of the sites can be confirmed as locations for cave bear worship.

Recent studies have shown that the cave bear most likely went extinct around 27,800 years ago, due to a variety of complex reasons. It is thought that although this bear went extinct around the time as a few other large mammals, its extinction was caused in part by its limited range and specialized diet. Its extinction occurred before most large mammals died out, however. Genetic studies resulted in the findings that the cave bear might have held a limited gene pool, which can cause a loss in viable breeding partners and eventual extinction. Unlike many large mammals, it is not thought that humans overhunted the cave bear, because there were not enough humans to kill them, although there was some level of competition between the two species. The most recent hypothesis on the extinction of the cave bear asserts that humans, whom were growing in number, took away viable habitat resources that the cave bears needed to survive during the winter, but this is still being researched.

Image Caption: reconstruction of a European cave bear (Ursus spelaeus). Credit: Sergiodlarosa/Wikipedia (CC BY-SA 3.0)