The common knowledge about the evolution of man from the ape that progressively stops dragging its arms along the ground might find the latest reveal in this field a little surprising. The scientific world is extremely dazzled to find out that a research in Kenya highlighted that two different species of early man lived side by side in the same place for almost half a million years.

Both fossils were found in 2000 east of Lake Turkana in Kenya as part of the Koobi Fora Research Project, which is affiliated with the National Museums of Kenya.

Susan Anton, associate professor of anthropology at New York University and co-author of the research, explains:  "The co-existence of the two species suggests that they were more like sister species, as opposed to homo habilus being the mother to homo erectus," she said.

The skull of Homo Erectus, that dates 1.55 million years and the 1.44 million years old upper jaw bone of Homo Habilis, found within walking distance oppose to the linear evolution theory which says that the first species, Homo Habilis evolved in Homo Erectus which turned into Homo Sapiens.

"Homo Habilis never gave rise to Homo Erectus. For a long time we believed that but now these two discoveries have completely changed that story," said Frederick Manthi, the palaeontologist who found the fossils east of Lake Turkana, in northern Kenya, in August 2000.

Fred Spoor, a professor of evolutionary anatomy at the University College in London introduced the idea that, like chimps and apes “they’d just avoid each other; they don’t feel comfortable in each other’s company,” he said.

This new discovery doesn’t mean that history should be re-written, “This is not questioning the idea at all of evolution; it is refining some of the specific points,” Anton said.

"The fact that they stayed separate as individual species for a long time suggests they had their own ecological niche, avoiding direct competition," said Idle Farah, director of the National Museums of Kenya.

Daniel Lieberman, a professor of biological anthropology at Harvard University, concluded that the Kenya discoveries show “just how interesting and complex the human genus was and how poorly we understand the transition from being something much more apelike to something more humanlike.”