'Gorrilas like early humans'

2007-12-01 13:15

Johannesburg - Research on 1.5 to two million-year-old fossils from South Africa showed that the gorilla pattern of growth was similar to that of some of humanity's extinct closest relatives.

The research was inspired by discoveries at Drimolen, a site near Johannesburg, South Africa, that is part of the Cradle of Humankind World Heritage Site, the University of Johannesburg said in a statement on Thursday.

It also found that the males were much larger than females - a greater difference in size then there is today. Research found that one male was likely dominant over a troop of females.

Their size coupled with the social structure would have made them vulnerable to predators.

"In the 1990s Andre Keyser, one of the scientists involved in the study, led the initial work at Drimolen and in 1994 his team discovered the most complete skull of any Australopithecine known at the time," the university said.

" The little skull... nicknamed "Eurydice" (from the Greek myth of Orpheus and Eurydice), was quite different from other members of the species, known as Paranthropus robustus."

"Eurydice showed us that sex differences in Paranthropus robustus were greater than we had previously thought.

'Distinctly smaller'

"While there are some other specimens from Drimolen that are just as large and robust as the ones from sites like Swartkrans, Eurydice is distinctly smaller than the other well-preserved specimens of this species," said Dr Colin Menter, from the University of Johannesburg (UJ)'s Department of Anthropology and Development Studies and co-director of current fieldwork at Drimolen.

Charles Lockwood, of University of London College's anthropology department, and lead author of the research, found that when the male specimens were sorted by age, they did not reach their full size until the middle of their adult lives.

"Before the Drimolen discovery, it had been thought that some of the smaller and less robust skulls from Swartkrans were females.

"What we realised is that these were males who had simply not completed their growth.

"The young adult males were in between the small females and the larger fully mature males in size. That is exactly what you see in some apes and monkeys," Lockwood said.

- SAPA