It would seem as if the 169-year old evolution theory is beginning to crack at the seams if the findings of Kenyan researcher, Dr Frederick Manthi, are anything to go by. The long-held view that the process of human evolution began with Homo Habilis and then Homo Erectus is now being faulted by this new finding.

Dr Manthi’s 7-year research suggests that Homo Habilis and Homo Erectus could actually have lived close to each other for 500,000 years. His research, just been published in the authoritative Nature journal, may lead to the re-writing of textbooks on natural science.

According to Dr Manthi, both Homo Habilis and Homo Erectus co-existed in the Illeret area of Marsabit County, along the Lake Turkana basin on the eastern side. As expected, his discovery has already sparked a storm of debate about its authenticity.

He had been conducting his research in collaboration with the Koobi Fora Research Project, which is based at Sibiloi National Park in Illeret. The project, comprising a group of international scientists, was established by Dr Louis Leakey, who first discovered fossils of Homo Habilis and Homo Erectus in the same area.

Dr Idle Farah, the director-general of the Museums, said Dr Manthi’s discovery was a critical part of the history of the world. One of the fossils Dr Manthi found is a well-preserved skull of Homo Erectus that dates back 1.55 million years.

It is the smallest Homo Erectus skull found anywhere in the world. Similar skulls have been found in Asia and Europe. The other fossil, dating back 1.44 million years, the researcher said, is the upper jaw bone of Homo Habilis.

Archaeologists say the evolution of humans over the past 2 million years is a succession of 3 species. First, it was Homo Habilis or the ape from which Homo Erectus evolved before transforming into Homo Sapiens or the modern man.

Dr Manthi’s discovery suggests that Homo Habilis and Homo Erectus co-existed, making it unlikely that one evolved from the former.

On the authenticity of the discovery, Dr Emma Mbua, the head of Earth Sciences at the Museums, said they still have to make more discoveries to strengthen this theory.

“There has been a view that has suggested that Homo Habilis very slowly evolved into Homo Erectus,” said Dr Susan Anton, a professor of anthropology at New York University. “Now we have the 2 cohabiting, so that can no longer be the case.”

The research was conducted by 9 scientists, including Dr Anton, Palaeontologist Meave Leakey and her daughter Louise Leakey, both explorers in residence at the National Geographic Society, and Fred Spoor of the University College London.