There are no clear transitional fossils in spite of rabid efforts to show otherwise and in spite of billions of fossils being uncovered. The closest potential candidate have all been fabricated hoax's. (Hoax's which clearly show how desperate some groups of individuals are in the support of their theory)
That simply isn't true. We have quite a large amount of fossils that show transition. I don't like just telling people they are wrong. So I'll give you a quick overview of the evidence. All of this can be checked via any bio-anthropology text book, professor, online encyclopedia...etc. I have multiple sources that will give you all the same information. I have held the bones of almost all of these species in my own hands, so I can personally verify the information, as well.
The Pleistocene had primate-like mammals. These looked very similar to rodents. They had no post-orbital bar, their eyes were not forward facing, they had no opposable digits, claws, rodent-like teeth, diastema (gap for canine teeth), and very tiny brains.
As we move into the Eocene, we have the Omomyids (
Teilhardina asiatica is one, and is considered to be as close of an example as we have to the stem primate), and the Adapids. There is a ~95% complete Adapid (
Darwinius masillae) fossil known as "Ida" from the Messel Pit in Germany. Ida shows many rodent characteristics, but she also has nails and an opposable hallux.
Other early anthropoid fossils include:
Eosimias ("Dawn Monkey") and
Aegyptopithecus. These range from ~50mya to about 33mya.
These all show the transition from rodent-like mammals to the characteristics we see in primates. Things like the presence of a post-orbital bar, forward facing eyes, grasping hands and feet, nails instead of claws, all with varied development.
Moving into the Miocene you have Proconsul (21-17mya), as well as species like
Kenyapithecus,
Ouranopithecus,
Sivapithecus and
Pryopithecs. However the latter three show characteristics more similar to modern great apes than humans, so they aren't considered part of the human lineage, but could present spliting point in the evolution of man and other apes.
From there we move into more familiar territory. I'll do a quick overview of the traits of each type specimen of each of the transitory species so you get can a feel for the the development of modern human characteristics.
Salhelanthropus tchadensis (7mya)
(Cranium only)
Foramen magnum position shows possible bipedalism
Non-honing canines
Thick enamel (ape characteristic)
Small brain (365 cc)
Facial prognathism
Orrorin tugenesis (6.2-5.65mya)
(Parts from 12 individuals)
Neck of femurs suggests bipedalism
Non-honing canines
Humerus shows they were also be arboreal
Ardipithecus kadabba (5.8-5.2mya)
(Teeth and post-crania)
Shows ape-like chewing
Toe shows possible evidence of bipedalism
Aridpithecus ramidus (4.4mya)
(45% complete)
Foremen magnum => bipedal capabilities
300-350cc cranial capacity for (ARA-VP-6/500 fossil only).
Os peroneum is a bone in the foot that allows for both an opposable toe and to stiffen the foot for "toeing off" (how humans walk). It's a more developed version of what is seen in A. kadabba. It show a slightly flared ilia (part of of hip) which is seen to a greater extent in humans.
Still many ape characteristics:
Large canines, smaller molars, ape-like enamel and diet, curved fingers, lower pelvis very chimp-like. Facial prognathism
Australopithecus anamensis (4mya)
Chimp like jaw, more human-like teeth.
Here we start to see sexual dimorphism (different sizes between males and females) developing.
Australopithecus afarensis (3.6-3.0mya)
(40% compelete) A.k.a "Lucy" (although many other specimens exist)
She has "mirrored" post crania, meaning that what she misses on one side is present on the other, so we have an idea of what her whole body looks like.
Knees, pelvis, feet (no longer has the divergent toe that we see in Ardipithecus) and foreman magnum all show habitual bipedalism.
Curved fingers show she was also arboreal. Facial prognathism
Cranial capacity (400-500cc)
NOTE: The Paranthropines also existed during this time, but they aren't believed the be ancestors to humans.
Australopithecus garhi (2.5 mya)
Cranial capacity 450cc
Humerus and femur are human-like (however, scientists have no yet confirmed that the post-cranial and skull are from the same individual).
Homo hablis (2.4-1.6mya)
First sure instance of tool use.
600cc cranial capacity
Smaller teeth, thinner enamel, parabolic dental arcade (human-like, compared to U-shaped type found in chimps).
The skull becomes rounder, less facial prognathism.
Seven well-known specimens
Homo erectus/ergaster (1mya-300kya)
Fully human gait
Cranial capacity 950-1000cc
Larger body size
Lower limbs of human proportions
Smaller jaw, face and teeth than previous specimen
Cranial vault sits high
Forehead
Almost no facial prognathism
Advanced tools
First to leave Africa and spread out throughout the New World
Specimens found in Africa, Europe and Asia.
After this point, the current, most common view point is that a
Homo species moved into Europe. This became
Homo antecessor, which became
Homo heidelbergensis, which became the Neaderthal. Humans most likely evolved from
Homo erectus in Africa and then proceeded to leave Africa and colonize the rest of the world (this is supported by genetic evidence). You have archaic humans that look very much like
H. erectus, and we also have possible human/Neaderthal hybrid fossils.