18 in the journal PLOS ONE.įollow Megan Gannon on Twitter and Google+. Compared with todays bears, this ancient creature, named Indarctos arctoides, had a. The study was led by paleobiologist Juan Abella, of the Autonomous University of Barcelona. Researchers recently studied a collection of penis bones from an extinct species of bear in Spain. The fact that Indarctos arctoides had a relatively long bacula suggests it was a sexually selected trait that females used to assess mate quality. Previous research has suggested bear species with strong sex differences tend to have shorter penis bones and mating systems where males take multiple mates and fiercely compete for females. It turns out that a bear paw skeleton is very similar to that of a human hand or a child’s foot. The fossil record shows that the male Indarctos arctoides would have been much larger than the female. With newspaper headlines across the country telling of human skeleton hand and foot remains being discovered, and citizens nearby fear the worst, forensic experts have found that many of these claims are, in fact, not human remains. Indarctos arctoides may have also had relatively large individual ranges and possibly a lower population density, giving rise to fewer sexual encounters, the researchers say. We sampled the ilium bone from black bears including animals reported on in a previous study (Fedorov et al. A long baculum, the study researchers say, could have served as a physical support during mating, helping to keep the female's reproductive tract open and in an optimal position for fertilization during these sporadic dalliances. Most of the bones of the skull are flat bones, except the mandible. The whole skull anchors muscles that hold the head up, allows the bear to chew, and form vocalizations. Black bear coats are usually black in color, but can range from black to dark brown. They are the commonest, most widely distributed and smallest of the bear family Ursidae. The shape of the claw differs between the bear species: black bear. Several black bear bones occurred in the collapsed sediment including a femur shaft lacking proximal and distal epiphyses, a carbonate-encrusted partial hand or. The length of the penis bone could reveal details not only about the sexual behavior of Indarctos arctoides, but also the species' ecological habits and mating system.īased on the size of baculum, the researchers think the bear likely had fewer but longer periods of intercourse than other mammals. The facial bones form the structure of the face, hold the eyes, and the organs for taste and smell and anchor the teeth. In black bears the last 6-8 weeks of gestation and the first 10-12 weeks of lactation occur in winter while the mother is in a dormant state, and reportedly does not eat, drink, urinate or defaecate. Black bears are the third largest mammal in Wisconsin, with elk (Cervus elaphus) and moose (Alces alces) the only larger mammals. Bears have five digits on each dextrous paw, each digit with a long non-retractable claw.
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