This table describes a few different features present on ape skulls and compares them in humans, chimpanzees, and gorillas. As a result of this size difference, male gorilla skulls are much larger than female gorilla skulls. Male gorillas typically weigh between 300 and 500 pounds, whereas females weigh between 150 to 250 pounds. Gorillas are very sexually dimorphic because male gorillas are much larger than females. This is when there are distinct physical differences between males and females of the same species. Gorilla brains are about 1/3 the size of human brains! A gorilla’s facial bones are much more robust than those of a human, however. The human cranium has a much larger volume than a gorilla’s cranium and houses a much larger brain. Skulls consist of the cranium (the brain case) and the splanchnocranium (the facial bones). Human skulls are 19 cm high, 15 cm long, and 18 cm wide. In fact, the average male gorilla’s skull is 16 cm high, 34 cm long, and 18 cm wide. Gorilla skulls are exceptionally large amongst primates. What is unique about gorilla skull size? A male eastern lowland gorilla Considering the timeline of mammal evolution (with the first mammal arising 65 million years ago), this is quite recent! The close evolutionary histories of gorillas and humans explain many similarities that appear between the species. The lineage that includes chimpanzees and humans diverged from a common ancestor with gorillas about 12-17 million years ago. For more about the difference between apes and gorillas, click here. As such, they are closely related to orangutans, chimpanzees, bonobos, and humans. They are the largest primate on Earth and are also a member of the great apes. There are two species of gorilla and four subspecies: western gorillas (including western lowland gorillas and Cross River gorillas) and eastern gorillas (including eastern lowland gorillas and mountain gorillas). Gorillas are large land mammals that live primarily in Rwanda, the Congo, Uganda, Angola, Cameroon, Central Africa, Equatorial Guinea, Gabon, and Nigeria depending on the subspecies. What is a gorilla? A western lowland gorilla This article will investigate how our skulls compare and what other interesting information skulls can reveal about a species. In actuality, the skulls of our not-so-distant gorilla relatives are quite similar to ours. They are also incredibly large! Within this colossal animal is a very interesting and complex skull that seems to be very different from a human skull. 'There's an aggression toward individuals that are not in their group.'īut chimps are often seen as friendly and cute animals because many facilities use preventive measures to prevent the aggression, he said.Gorillas are beautiful and unique creatures. 'They can adapt very well to their environment but that doesn't preclude that they are territorial and they are violent and wild animals first,' Ross said. The emotional impulses also play a role in how aggressive they can become, he said. They directed the violence towards Andrew whom they feel was infringing on their territory.'Ĭhimpanzees have a wide range of emotions and they are similar to what humans experience, yet they are known to have erratic and unpredictable impulses, Ross said. 'This is why we come to the conclusion, as far as our expertise goes, that it was a territorial defense. 'They have no anger,' Cussons said of the chimps. The two chimps saw Oberle's crossing the fence into the chimps' space as a violation of their territory, prompting them to take action, Cussons said. In Thursday's case, however, an internal investigation by the Jane Goodall Institute near Johannesburg showed that the chimps might not have intended to be malicious, Eugene Cussons, director of the institute, told 'Good Morning America' today. Such physical lack of control can potentially lead some chimps to become more aggressive when physical.

As a result, sometimes chimps use more of their muscle strength than necessary, according to Walker's theory, published 2009 in the journal Current Anthropology. In chimps, the muscle fibers closest to the bones - those deemed to be the source of strength of both chimps and humans – are much longer and more dense, so a chimp is able to generate more power using the same range of motion, Ross of the Lester Fisher Center said.Īlso, unlike humans, chimpanzees have less control over their muscles.

Research suggests the difference in strength between the two lies in the muscle performance. Indeed, chimpanzees have been shown to be about four times as strong as humans comparable in size, according to evolutionary biologist Alan Walker, formerly of Pennsylvania State University.

Adult chimpanzee vs human skulls