Ardi, Ardipithecus Ramidus

Ardipithecus Ramidus... ...or "Ardi" as she is nicknamed, lived 4.4 million years ago - that's more than a million years older than "Lucy" - and is our earliest definitely known ancestor. Saw a fascinating programme about her discovery and the piecing together off her incredibly fragile partial skeleton. They found her in 1994 and only this year have they finished the process of restoration. She was a true bipedal. She didn't knuckle walk like the Great Apes, but she had a gripping foot with an opposable big toe. This differentiates her from Lucy, who had a foot more or less like ours. Ardipithecus as a species couldn't walk far or fast, but was, nonetheless, walking without the help of her hands. So now we know that we developed our modern human foot between 4.4 and 3.2 million years ago. It is also very likely that we evolved in a more forested environment than used to be thought. Her brain was about the size of a chimp's, but she had smaller canines (MUCH smaller) than a chimp. This, and the species' ability to walk without the use of hands, have led to the speculation that this is where our modern pair bonding behaviour started - females were NOT selecting males on the basis of their size and aggression. It is very possible that they were selecting them on the basis of their ability to bring food, something much easier to do when both hands are available for carrying. This allowed the females more time to care for their young, presumably hidden away in a comparatively safe pace, thus giving a reproductive advantage in that more children were likely to reach adulthood. There are also, apparently, signs of an even older ancestor named Ardipithecus Kabaddi. This possible ancestor is dated at around 6 or 7 million years old if I remember it correctly. So far, only a few teeth and bone fragments have been discovered, plus a possible skull. Source and Discussion