MAJOR DISCOVERIES OF THE WORMIL PROJECT

 

KADANUUMUU (KSD-VP-1/1)

Partial skeleton of Australopithecus afarensis

In 2005, Alemayehu Asfaw discovered the first element of the partial skeleton, a proximal ulna fragment. Over the next four years, the team excavated an area of 85 square meters and collected more than 400 pieces of bone, representing about 40% of the skeleton. Kadanuumuu is a large, male individual belonging to Australopithecus afarensis, the species to which the famous Lucy belongs. Radiometrically dated to about 3.6 Ma, Kadanuumuu is at least 400,000 years older than the famous Lucy. Many of its preserved elements, such as the complete scapula (shoulder blade), are not well represented in the hominin fossil record, subsequently, it has provided us with new insights into limb proportions, shoulder girdle anatomy, thoracic form, and locomotor adaptation in early hominins. A comprehensive volume describing Kadanuumuu was published by Springer as part of their Vertebrate Paleobiology and Paleoanthropology Series in 2016. The initial description of the skeleton was published in the Proceedings of the National Academy of Sciences.

 
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BURTELE FOOT (BRT-VP-2/73)

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Foot bones are among the rarest elements in the hominin fossil record. The first element of the Burtele Foot was recovered by Dr. Stephanie Melillo in 2009 (then a graduate student). The Burtele Foot consists of eight mostly intact bones of the right foot that reveals an unexpected mosaic of primitive and derived features - most significantly, an opposable big toe that suggests that it was not a habitual biped like Australopithecus afarensis and may have had a significant arboreal component to its locomotor repertoire. Radiometrically dated at 3.4 Ma, it is contemporaneous with A. afarensis and a million years younger than Ardi (Ardipithecus ramidus), found at the nearby site of Middle Awash, who also possessed an opposable big toe. Although it is not yet possible to assign the foot to a species, the Burtele Foot is the first conclusive evidence indicating that there were at least two species of hominins living in close proximity during the Middle Pliocene. The description and comparative analysis of the specimen was published in Nature.


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AUSTRALOPITHECUS DEYIREMEDA

In 2015, the WORMIL team named a new species from sediments dated to between 3.3 and 3.5 Ma at Woranso-Mille - Australopithecus deyiremeda. This new species is described from several cranio-dental elements, including two mandibles, maxilla, and several isolated teeth. Australopithecus deyiremeda differs from A. afarensis in terms of the shape and size of its teeth and the robust architecture of its lower jaw. The anterior teeth are also relatively small, which may indicate a different diet from A. afarensis. This species confirms that A. afarensis was not the only potential human ancestor during the middle Pliocene of what is now the Afar region of Ethiopia and that Woranso-Mille was home to at least two different species of early hominins, if not three. This species was described and named in the journal Nature.


NEFURAYTU MANDIBLE (NFR-VP-1/29)

NFR-VP-1/29 is one of the most complete and largest mandibles assigned to Australopithecus afarensis and likely represents a male individual. It was found in sediments radiometrically dated to 3.33-3.2 Ma. Its discovery confirms the existence of A. afarensis in the Woranso-Mille study area in close spatial and temporal proximity to the other middle Pliocene hominin taxa found in the area, i.e. A. deyiremeda and the Burtele Foot. Description and comparative analysis of the mandible was published in Journal of Human Evolution.