Gray wolf (Canis lupus) anatomy
The bones of wolves are strong, giving them the power to bring down large prey such as caribou. The narrow shoulder blades and long limb bones limit flexibility but make wolves efficient runners.
Wolves are sleek but also very muscular. Large trunk muscles drive the slender legs, allowing the animal to run fast and leap far. Strong neck muscles hold up the head, and powerful jaw muscles give wolves their ferocious bite.
Although its structure is very similar, a wolf’s brain
is both larger and heavier than of a domestic dog. Other features of the
nervous system are virtually identical to those of dogs.
Male wolves have to sperm-producing testes located in an external scrotal sac that hangs between the back legs. The penis is ejaculated during sex, has a supporting bone called the baculum.
Female wolves have two egg-producing ovaries. From each ovary, a fallopian tube leads to the uterus, which has two horns (it is bicornuate). The uterus expands greatly during pregnancy and can hold up to 11 cubs.
As is typical of canids, the wolf has a long, narrow skull. The powerful jaws house an impressive array of teeth suited to a carnivorous diet. The sharp fangs – the canines – can reach 2 inched (5cm) long.
The wrist bones of wolves are fused for extra strength. When the toes are splayed, a wolf can grip onto slippery, uneven, or steep surfaces. When closed, the toes form a strong paw.