At one point, it was indeed thought to be the case that Ramapithecus was one of the earliest humans, though subsequent research disproved the notion. First, let's try to set the record straight and then we'll learn how Ramapithecus got so much credit early on.
The discovery of fossilized remains from an approximately 4.4-million-year-old hominid helps to determine at what point in human evolution man split from the chimpanzee. Anthropologist Tim White found this fossil in the Middle Awash region of Ethiopia in 1994. The specimen, classified as Ardipithecus ramidus, had both ape and chimp features, but later paleontological finds have demonstrated that this species walked upright, and was probably a human ancestor [source: BBC].
In 2001, a skull was found in the northern deserts of Chad by Ahounta Djimdoumalbaye. He called it Tournaï, which means "hope of life" in the African language of Goran. Its species name is Sahelanthropus tchadensis. Tournaï had the skull of an ape but the facial features of a human. Approximately 6 to 7 million years old, Tournaï showed that human-like hominid apes appeared more than 1 million years earlier than previously thought.
In 2000, Brigitte Senut and Martin Pickford discovered five pieces of a hominid ancestor dating back approximately 6 million years. Orrorin tungenensis (the Tugen term for "original man") had the teeth and build for bipedal locomotion associated with humans rather than with chimps. This may well be the first species of hominids after the evolutionary split with chimpanzees. Another 6-million-year-old species, Ardipithecus kadabba, is also an early hominid ancestor, based on dental comparisons between it and chimpanzees.
Earlier times told a different story, however. Many biology textbooks from the 1970s and 1980s describe Ramapithecus as the first direct ancestor of modern humans. Here's why: A graduate student by the name of G. Edward Lewis discovered the first Ramapithecus fossils in 1932 in northern India. More Ramapithecus fragments were found in various locations. In 1960, Elwyn Simons pieced together some jawbone fragments and announced that he'd found the first step in the divergence of human-like animals from ape-like animals.
But in the late 1960s, two biochemists were analyzing the blood proteins among various animal species. They concluded that the ape-human divergence must have occurred some 10 million years ago, but radioactive dating had pegged the Ramapithecus fossils at 14 million years old. Doubts arose. Then, in 1976, David Pilbeam found a complete Ramapithecus jaw, which clearly showed an apelike design. Today, scientists believe Ramapithecus may have been a distant ancestor to the orangutan.
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