There is a lot of debate about when modern humans evolved. One popular theory says that they appeared first in Africa.
But recent research suggests that early modern humans also lived in Europe and Australia. Those early modern people share traits with both Neandertals and archaic humans, according to scientists.
Humans evolved from apes
The origins of modern humans are still under debate, but researchers agree that at some point in time humans separated from chimpanzees. This was around 9.3 million years ago, during the Miocene epoch.
Evolutionary biologists have two main strategies for answering this question: “top-down” and “bottom-up.”
Top-down approaches use analysis of living apes such as chimpanzees to reconstruct the last common ancestor of humans and chimps. They are particularly helpful when fossils of extinct apes are also available.
However, fossils of extinct apes have posed an important problem because they are often difficult to identify and study. In particular, they lack the detailed morphology of living apes.
This has made it difficult to know what the last common ancestor of humans and other apes looked like. Until recently, it was believed that our common ancestor looked a lot like a chimp with features such as a short back and arms and hands that enabled grasping and swinging in branches.
Humans evolved from Neandertals
The Neanderthals evolved from a common ancestor with modern humans about 700,000 years ago. Neandertals lived in Western Asia for 30,000-50,000 years, interbreeding with non-African modern humans.
They were very skilled hunters whose diets were primarily meat. They killed butchered red deer (Cervus elaphus), bison (Bison priscus), horses, and other species of large game.
In addition, they developed fire from around 200,000 years ago to help them survive in cold climates. They also developed a wide variety of tools, including stone tools.
These were essential to their survival. They also developed a complex social system that included complex communication.
While some researchers believe that Neanderthals went extinct because of climatic factors, others argue that they were largely assimilated into populations of early modern humans. This hypothesis is supported by genetic evidence that indicates that modern European and Asian DNA contains 1-4% Neanderthal genes.
Humans evolved from Homo erectus
When modern humans evolved, they grew to be a larger and more muscular species. Their body proportions were also more modern than those of their ape-like ancestors, and they had a better ability to adapt their diet to changing climate conditions.
The earliest fossils attributed to Homo erectus were discovered by a Dutch army surgeon, Eugene Dubois, on the island of Java in Indonesia (Dubois 1894). He found the remains of a cranium at Trinil along the Solo River, where the skull cap, brow ridges, and rear skull were still well preserved.
The skullcap and femur resembled those of Australopithecus, but the cranium had a lower braincase and a more angled rear skull, features more similar to H. erectus. It had a large cranial capacity, which exceeded that of its ape-like ancestors.
Humans evolved from Homo neanderthalensis
In a long evolutionary journey that began with ape-like movement six million years ago, modern humans evolved gradually, intermingling with other human species and sometimes interbreeding. This was particularly true in Europe and Asia, where Neanderthals were found.
The first known Neanderthal fossils were unearthed in 1856 in a quarry near Dusseldorf, Germany. The remains included a robust cranial vault with a massive arched brow ridge and several limb bones.
These skeletons had some characteristics that are associated with cold-climate adaptation: they had relatively short distal limbs (lower arms and legs), broad and deep ribcages, and large articular ends of the tibia and femur.
They also had distinctive facial features, including a prominent brow ridge above their eyes and a wide nose that protruded from the face. These characteristics are thought to have helped Neanderthals survive in colder, drier environments.