Final answer:
The term hominoid encompasses modern and extinct great apes and humans, characterized by larger brain sizes and reduced prognathism. Hominins, a subgroup of hominoids, notably includes species adapted for bipedal locomotion and with advanced tools use and social behaviors.
Step-by-step explanation:
The term hominoid refers to the group that includes all modern and extinct great apes, including humans, gorillas, chimpanzees, and orangutans. Hominoids share common features, such as a larger brain size compared to other primates, reduced prognathism (a less protruding jaw), complex social structures, and, in most cases, the ability to use and make tools. Members of this group possess varying degrees of bipedalism, though not all are fully adapted for walking on two feet. The fossil record and DNA analysis suggest that humans and chimpanzees diverged from a common ancestor about six million years ago, marking the evolution of early hominin species such as Australopithecus, Homo habilis, and Homo erectus. These hominins are known for key adaptations like upright posture and increased brain capacity, which were crucial for the development of complex behaviors such as language and culture.
Common features of hominoids include:
- Larger brain size
- Reduced facial protrusion (prognathism)
- Complex social behavior
- Capability for language and cultural development
- Use of tools
- Increased bipedal locomotion in hominins