LH 4
LH 4 (Laetoli Hominid 4) is the scientific name for a well-preserved fossil lower jaw that was recovered in Laetoli ( Tanzania ) in 1974 and identified in 1978 as a holotype of the species Australopithecus afarensis . The fossil was found on the surface by Maundu Muluila, a colleague of Mary Leakey , first presented in 1976 in the journal Nature and dated to an age of 3.59 to 3.77 million years. Tim White published a more detailed description of the find with exact dimensions and numerous illustrations the following year .
The lower jaw LH 4 comes from an adult individual, both ascending lower jaw branches (rami mandibulae) are missing. Eight molars with largely complete crowns and some broken anterior teeth remained , which in 1976 - like similar finds from Laetoli and Hadar - were not assigned to a specific species. The reason for this reluctance was that the molars of the Laetoli finds showed similarities in terms of their size and morphology both with the "graceful" Australopithecines ( Australopithecus africanus ) known from South Africa and with archaic representatives of the genus Homo ( Homo habilis ), which in East Africa had been discovered; most likely an assignment of the finds to the earliest representatives of the genus Homo , argued Leakey et al. 1976.
According to the first description of Australopithecus afarensis, LH 4 was selected as the holotype in 1978 because the petrified lower jawbone shows the typical characteristics of the species particularly clearly and because it was described in detail as early as 1977. The naming of the species by Donald Johanson , Tim White and Yves Coppens with reference to the Afar region in Ethiopia was justified in the first description by the fact that the majority of the fossils identified as paratypes were discovered at the Ethiopian site explored by Johanson and Coppens . In fact, only around two dozen teeth and jaw fragments were named from the area in Tanzania explored by Mary Leakey, besides the holotype, but several hundred from Ethiopia.
literature
- Donald Johanson, Tim White and Yves Coppens: A New Species of the Genus Australopithecus (Primates: Hominidae) from the Pliocene of Eastern Africa. In: Kirtlandia. Volume 28, 1978, pp. 1–14, full text (PDF)
- Donald Johanson and Maitland A. Edey: Lucy. The beginnings of mankind. 4th edition. Piper, 1992, pp. 345-362, ISBN 3-492-11555-1 .
Web links
- modernhumanorigins.net : Illustration of LH 4
Individual evidence
- ^ A b Donald Johanson , Tim White and Yves Coppens : A New Species of the Genus Australopithecus (Primates: Hominidae) from the Pliocene of Eastern Africa. In: Kirtlandia. Volume 28, 1978, pp. 1-14, full text (PDF) .
- ^ Mary Leakey et al .: Fossil hominids from the Laetolil Beds. In: Nature , Volume 262, 1976, pp. 460-466, doi : 10.1038 / 262460a0
- ↑ Tim White : New fossil hominids from Laetolil, Tanzania. In: American Journal of Physical Anthropology , Volume 46, No. 2, 1977, pp. 197-229, doi : 10.1002 / ajpa.1330460203
- ^ Donald Johanson, Maurice Taieb: Plio-Pleistocene hominid discoveries in Hadar, Ethiopia. In: Nature , Volume 260, 1976, pp. 293-297, doi : 10.1038 / 260293a0