What is significant about Australopithecus?

Australopithecus is significant primarily because it represents one of the earliest known bipedal hominids, marking a crucial point in human evolutionary history. Its ability to walk upright on two legs is a defining characteristic that set the stage for the development of later hominids, including the genus Homo, which includes modern humans. This adaptation to bipedality is believed to have facilitated the use of tools and the ability to traverse varying landscapes, contributing to survival and evolutionary success.

The other options do not accurately reflect the characteristics or the historical significance of Australopithecus. For instance, Australopithecus is not known for using fire; that skill emerged later with Homo species. It also lived between approximately 4 million to 2 million years ago, well before the stated timeframe of 1 million years ago. Additionally, Australopithecus had a smaller brain size compared to modern humans, which further emphasizes its distinct place in the evolutionary timeline rather than suggesting it had greater intelligence or brain capacity than contemporary humans.