The earliest members of the genus Homo a. had a larger brain compared to other hominins. b. probably hunted dinosaurs. c. lived about 4 million years ago. d. were the first hominins to be bipedal.

Verified step by step guidance

1. Identify the characteristics of the earliest members of the genus Homo by reviewing the evolutionary history of hominins.
2. Understand that the genus Homo is distinguished from other hominins primarily by brain size, tool use, and other anatomical differences.
3. Recognize that dinosaurs became extinct about 65 million years ago, long before any hominins, including members of the genus Homo, appeared.
4. Recall that the first bipedal hominins appeared earlier than the genus Homo, with species such as Australopithecus being bipedal.
5. Determine the approximate time period when the earliest members of the genus Homo lived, which is generally accepted to be around 2.5 million years ago, not 4 million years.

Key Concepts

Genus Homo

The genus Homo includes modern humans and our closest extinct relatives. Members of this genus are characterized by larger brain sizes compared to other hominins, which is associated with advanced cognitive abilities. The emergence of Homo species marks a significant evolutionary step in the development of human traits, including tool use and social behavior.

Bipedalism

Bipedalism refers to the ability to walk on two legs, a key adaptation in human evolution. This trait distinguishes early hominins from other primates and is linked to changes in skeletal structure, such as the shape of the pelvis and the alignment of the spine. Bipedalism allowed for more efficient locomotion and the use of hands for tool-making and carrying objects.

Hominin Evolution Timeline

The hominin evolution timeline outlines the development of human ancestors over millions of years. Early members of the genus Homo appeared approximately 2.5 million years ago, following earlier hominins like Australopithecus, which lived around 4 million years ago. Understanding this timeline is crucial for contextualizing the evolutionary significance of traits such as brain size and bipedalism.