READ: Gallery — Human Ancestors

Explore the images of this gallery and consider the genetic differences and similarities between humans and other species.

The evolutionary path that led to modern humans goes back millions of years and merges with the path that also produced all of the primates, including chimpanzees – one of our closest relatives.

Similar DNA isn't the only thing we have in common with our chimpanzee relatives. Primatologists like Jane Goodall and Dian Fossey demonstrated that primates share many other characteristics with humans. Chimpanzees have been observed using simple tools and aspects of their behavior and social interaction mirror that of humans.

A modern way of studying and classifying different creatures is by comparing their DNA. All life on Earth shares this important molecule and the similarities and differences between the DNA of all living organisms separates one species from another. Humans and chimpanzees have a very similar genetic code.

Homo erectus, sometimes called Homo ergaster, lived between about 1.9 million years ago and 143,000 years ago. The bodies of this species shared the same general proportions as that of humans and study of their teeth has shown that their growth rates were similar to that of the great apes. Homo erectus are thought to be the first human ancestors to have migrated out of Africa and there is evidence that they built campfires and made stone tools.

Homo habilis was one of the earliest species of the genus Homo and had a slightly larger braincase than its ancestors. Thought to be one of the first species to make stone tools, Homo habilis had long arms and a face similar to that of its ape ancestors.

One of the most important ways that archaeologists can learn about human ancestors is by studying their fossils and material remains. Looking closely at ancient teeth can help distinguish one species from another and can also reveal important information about diet and lifestyle.

Acheulean stone tools like these were made by Homo erectus and represent a revolution in toolmaking some 1.6 million years ago. Our ancestors made the multi-purpose tools (sometimes referred to as hand-axes) by flaking off part of the surface to get a better edge and used the pear-shaped tools for digging, cutting wood or other plant material and for cutting and skinning game.

Our ancestors made repeated migrations out of Africa. The first time is thought to have been about 1.8 million years ago when Homo erectus traveled into Eurasia, eventually going extinct. More recently, the ancestors of modern humans moved from Africa to Eurasia between 50,000 and 60,000 years ago.