Sites: All specimens were found east of Lake Turkana. The two most important sites in this area are Kanapoi and Allia Bay.
Age: 4.2 - 3.9 million years ago Type specimen: KNM-KP 29281. This is a mandible without the ascending rami but with all the teeth present. Specimens:
Cranial capacity: Cranial architecture: Dentition: Thick enamel, also seen in later hominids, suggest a diet of hard-to-chew foods. The size and shape of the teeth are however, primitive relative to later hominids. Anatomically the dentition shows largely ape-like characteristics: large canines, parallel tooth rows and asymmetrical premolars and molars. The mandibula also shows primitive traits, similar to species from the Miocene and modern apes. A shallow palate, though primitive, is shared with Australopithecus afarensis. In general, the dentition is primitive, but features not seen in earlier hominids are starting to appear. The thickened tooth enamel and smaller length to breadth ratio are also similar to A. afarensis. Postcranial: The partial tibia, KNM-KP 29285, consisting of proximal and distal ends, has anatomical features indicating bipedalism, with lower upper limbs suggesting a climbing locomotion. Environment: The area where A. anamensis lived was most likely a varied environment, with a mixture of open grassland, bush and forest. The lowest level in which A. anamensis was found, dates to 4.12 million years ago. At that time, an ancient lake, Lake Lonyumun, dominated the landscape. Length and weight: 127 to 152 cm, 46 - 55 kg Tools: Ancestor: Descendants: Found in the same region and predating "Lucy", A. anamensis could possibly be the ancestor to A. afarensis. General: Oldest member of the genus. Dentition and jaws indicate a hominid, joint surfaces of the lower leg a bipedal gait. The first specimen was discovered in the Kanapoi region of East Lake Turkana by a team from Harvard University. It was only recognised 30 years later. The next examples were only found in the early 1990's by Meave Leaky and colleagues from the National Museum of Kenya. The most significant aspect of A anamensis is that this species, with a similar but more primitive anatomy than that of A. afarenis, makes it a good precursor to Lucy's species. References:
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KNM-KP 29281 is considered the type specimen and consists of a mandible with teeth, but lacking ascending rami. The fossil was discovered in 1994 at Kanapoi and has an estimated age of 4.4 million years. The teeth are relatively large in comparison to body size of A. anamensis. The back teeth are large relative to the front teeth. Both traits are characteristic of all Australopith species.
KNM-KP 29283 consists of a maxilla and palate
KNM-KP 29285 consists of a partial tibia and was discovered at Kanapoi, Kenya in 1994. The shape of the bone indicates that A. anamensis most likely walker upright.
The overall size indicates A. anamensis was larger than both Ardipithecus ramidus and A. afarensis.
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