Question

Answer one of these three questions. 1] Name and describe the 3 major evolutionary models, including their associated researchers, species, locations, evidence, time line etc. 2] Describe 3 traits unique to the crania, dentition and post crania for these species; Australopithecus aferensis, Homo erectus, Homo heidelbergensis, Homo neandertalensis and Homo sapiens. 3] Describe in detail the environmental situation and cultural inventions and capabilities concerning Homo erectus leaving Africa.

Answer 1

Since only one of the three questions have to be answered, answering the second question here. The carnia here refers to the skull, dentition to the teeth which in turn affect the shape of jaws and post-crania refer to all bones following the skull, from vertebral column to limb bones and joints.

2. a. Australopithecus aferensis - Crania: The crania was more ape-like with low slopping forehead, prominant eye ridges. 'Lucy' is the most famoue example of such species.

Dentition: Their canines were intermediate between those in apes and humans with a diastema present between them and the adjacent teeth. Their molar on the other hand had the human type Y-5 pattern

Post-crania: The spinal cord instead of appearing from the back, appeared from the central part of the skull

b. Homo erectus - Crania: Their crania was similar to the modern humans with 1000 cubic centimeters capacity with the skull found to be relatively flat

Dentition: The size of molars and pre-molars were greatly reduced which were similar to modern humans

Post-crania: They had shorter limbs that were not suited for climbing with longer legs that were better adapted for running and walking (indicating a shift from tree climbing behaviour)

c. Homo heidelbergensis - Crania: They were larger than those in H. erectus but the rear end of the skull was more rounded with expanded parietals and broadened forehead. The skull also had post-orbital (behind eyes) constriction.

Dentition: A diastema was presnt behind the third molar called the retromolar space, the teeth were arranged in a parabolic shape on the jaw

Post-crania: The limbs were similar to humans with the same proportions

d. Homo neandertalensis - Crania: The back of the skull had a bulge called occipital bun with a depression for muscle attachement

Dentition: They also had the retromolar space but with larger teeth sizes as compared to the modern humans and lacked a chin (that gives distinctive shape to skull)

Post-crania: Pelvis larger then those in humans bringing about a change in posture and limb bones had large joints affecting the way they move

e. Homo sapiens: Crania: No post-orbital constriction and no square eye sockets (commonly called orbits), the skull has a projecting nose bone with limited brow ridge

Dentiton: There is no retromolar space and teeth are the smallest compared to all other species

Post-crania: Pelvis is narrower with lower limbs longer then upper limbs enabling bipedal movement