No. The percentage of hominid bones from the human fossil record for 1.0 to 3.8 million years ago is very sparse, since upto 2001 only 243 specimens are known. From about 75 known individuals, some of them are represented by only a single tooth or bone fragment containing identical bone material to be classified as transitional forms from Hominids to Homo sapiens. However, evolutionary connections from Australopithecus to Homo erectus, including the evolutionary relationships between Habilis, Ergaster and Erectus, are in need of further research since techniques able to extract DNA from the bones of any australopithecine for comparison with modern human DNA are not yet proven.
"Hominid fossil remains are precious since complete skeletons are extraordinarily rare. Teeth and lower jaws, and the facial and upper cranial bones of the skull, are the most common fossils to survive from any period. Skulls are almost never found intact but must be reconstructed from fragments. Thigh bones are next most often retrieved, while remains of the feet, hands, pelvis or spine are extremely rare. Specific behavioral conclusions require specific parts of the skeleton. For example, adaptation for a crouching or upright posture can be inferred from the connection of the spine to the skull, but bipedalism (habitual walking on two legs) requires evidence from bones involved in the thigh, knee, or foot joints. An opposable thumb requires evidence from wrist or hand bones".
"The early hominins share a important trait such as nearly efficient bipedal locomotion as humans. The bones of their pelvis, or hip region, were shortened from top to bottom and bowl-shaped like homo sapiens, but unlike apes. This made the pelvis more stable for weight support when standing upright or moving bipedally. The longer ape pelvis is adapted for quadrupedal locomotion. Early hominin leg and foot bones were also much more similar to Homo sapiens than to those of apes. This is consistent with the likelihood of early hominin bipedalism."
Currently there are two main categories of transitional fossils such as Australopithecus and Homo and several sub species between the Ardipithecus ramidus which lived 4.4 million years ago and Homo sapiens sapiens, Cro-Magnon I who lived 30,000 years ago.
They are classified not in order as,
(1) Australopithecus afarensis AL 288-1 a.k.a Lucy, 2.95 and 3.85 million years ago/Australopithecus africanus, Taung Child, 2.1-3.3 Million years
(2) Homo erectus, D3444/KNM-WT 15000, 1.43 to 1.9 Million years/Homo habilis, KNM-ER 1813, OH24-fossils Olduvai Hominid, a Homo habilis, include a partial lower jaw, bones of the braincase and hand bones 1.4-2.4 Million years/ Homo ergaster (early H. erectus), KNM-ER 3733, 1.75 Million years ago
(3) Homo heidelbergensis, "Rhodesia man," 700,000 to 200,000 years ago
(4) Homo sapiens neanderthalensis La Ferrassie 1, La Chappelle-aux-Saints, Shanidar 1, 230000–29000 years
The author Bruce MacEvoy refers the above data from From Lucy to Language by Donald Johanson & Blake Edgar (Simon & Schuster, 1996), The Last Human by G.J. Sawyer, Viktor Deak, Esteban Sarmiento and others (New Haven: Yale University Press, 2007) and The First Humans: Human Origins and History to 10,000 BC. New York: HarperCollins, 1993.
The first hominid was discovered in 1924 by Raymond Dart, an anatomy professor at Johannesburg in South Africa. The most significant difference between members of Homo and Australopiths, with which they overlapped, was their significantly larger brains (about 30 percent larger, though still small compared to modern humans). While the skull had many apelike features such as a projecting face and a small brain, it had distinctly human features as well—for example, a rounded jaw unlike the pointed jaw of apes. The ventral position of the foramen magnum (the hole at the base of the skull from which the spinal cord emerges) suggested that the creature had walked upright. More than 300 specimens of A. afarensis have since been discovered. In the last 10 years, three additional kinds of australopithecines have been reported. These seven species provide ample evidence that australopithecines were a diverse group, and additional species will undoubtedly be described by future investigators.
Scientists further divide the evolution of the modern human genus into three periods: early, middle, and late. Species of early Homo, among them Homo habilis, resembled Australopiths in many distinct ways, but they had smaller teeth and jaws, more modern-looking feet, and hands capable of making tools. They probably lived from between 2.5 or 2.3 million and 1.6 million years ago. Homo habilis co-existed with Homo erectus in Eastern Africa for almost half a million years.
The middle Homo species, including Homo erectus, evolved anatomically to be more similar to modern humans but their brains were relatively small (though bigger than australopiths). At the beginning of its time range, around 1.9 Million years ago, H. erectus coexisted in East Africa with several other early human species including Homo rudolfensis, Homo habilis, and Paranthropus boisei. At the end of its time range, around 143,000 years ago, it coexisted with Homo sapiens and possibly Homo floresiensis in Indonesia. Homo erectus was a very successful species of the middle period; fossils have been found throughout Africa, Europe, and much of Asia, and the species may have survived for more than 1.5 million years. Homo ergaster, which differs from the Asian H. erectus fossils in some details of the skull (e.g. the brow ridges differ in shape, and erectus would have a larger brain size). H. ergaster include fossils such as the Turkana boy and ER 3733. H. ergaster does not show significant promise of lasting as a separate taxon due to several factors. It has not been shown to be significantly different from erectus to require the designation of a new hominid species, and it has not been shown to be closer to modern humans morphologically.
Comparison of Neanderthal and modern human DNA suggests that the two lineages diverged from a common ancestor, most likely Homo heidelbergensis, sometime between 350,000 and 400,000 years ago – with the European branch leading to H. neanderthalensis and the African branch (sometimes called Homo rhodesiensis) to H. sapiens. Archaic forms of Homo sapiens first appear about 500,000 years ago. The term covers a diverse group of skulls which have features of both Homo erectus and modern humans. The brain size is larger than erectus and smaller than most modern humans, averaging about 1200 cc, and the skull is more rounded than in erectus. The skeleton and teeth are usually less robust than erectus, but more robust than modern humans. Many still have large brow ridges and receding foreheads and chins. There is no clear dividing line between late erectus and archaic sapiens, and many fossils between 500,000 and 200,000 years ago are difficult to classify as one or the other.
Neanderthal 1 was the first specimen to be recognized as an early human fossil. The specimen had oval shaped skull with a low, receding forehead and distinct browridges, the thick, strong bones. Several years after Neanderthal 1 was discovered, scientists realized that prior fossil discoveries in 1829 at Engis, Belgium, and in 1848 at Forbes Quarry, Gibraltar—were also Neanderthals.
After the discovery of Dmanisi fossil in 1991, it seems likely that fossils attributed in the past to Homo ergaster, Homo habilis, Homo rudolfensis (all in Africa), Pithecanthropus erectus (in Java) are all members of single evolving species, Homo erectus, showing variations with the passage of time (over a million years) and over large geographical distances. With evolution, species are not permanently stable entities. Sometimes they intergrade with other species and its close to impossible to describe completely with typological labeling.
