Australopithecus anamensis
I can’t keep up with the evo stories that keep coming out.
Here are more hominid fossils from Ethiopia, about 4.1 MYA, mostly teeth and a couple femurs. I hasten to note that these finds add to our understanding of Au. anamensis; the species is documented by more than a few teeth. At the link in Nature, is an interesting chart of the possible “phylogenetic” relationships between the hominid species. Did some branch off from earlier ones, or do they represent a single continuum? Also note that these new finds “extend the range” of Au. anamensis, by 1000 km.
Asa Issie, Aramis and the origin of Australopithecus : Nature
The origin of Australopithecus, the genus widely interpreted as ancestral to Homo, is a central problem in human evolutionary studies. Australopithecus species differ markedly from extant African apes and candidate ancestral hominids such as Ardipithecus, Orrorin and Sahelanthropus. The earliest described Australopithecus species is Au. anamensis, the probable chronospecies ancestor of Au. afarensis. Here we describe newly discovered fossils from the Middle Awash study area that extend the known Au. anamensis range into northeastern Ethiopia. The new fossils are from chronometrically controlled stratigraphic sequences and date to about 4.1–4.2 million years ago. They include diagnostic craniodental remains, the largest hominid canine yet recovered, and the earliest Australopithecus femur. These new fossils are sampled from a woodland context. Temporal and anatomical intermediacy between Ar. ramidus and Au. afarensis suggest a relatively rapid shift from Ardipithecus to Australopithecus in this region of Africa, involving either replacement or accelerated phyletic evolution.
The last quarter-century of research into hominid evolution in Africa greatly extended knowledge of early Australopithecus. Discoveries at Hadar and Laetoli during the 1970s led to the recognition of Au. afarensis, described as a geographically and ecologically widespread, bipedal, megadont, small-brained hominid species lineage. Until recently, the origins of Australopithecus were obscured by a sparse fossil record.
In 1994, the smaller-toothed, more primitive hominid Ar. ramidus was described from Aramis, Ethiopia (hominid refers to the human clade subsequent to divergence from our common ancestor with chimpanzees). These finds were followed in rapid succession by the description of Au. anamensis from Kenya, and the naming of three Late Miocene taxa (Ardipithecus kadabba, Ethiopia, approx 5.5–5.8 million years (Myr) ago; Orrorin tugenensis, Kenya, approx 5.7–6.0 Myr ago; and Sahelanthropus tchadensis, Chad, approx 6–7 Myr ago). Relative to extant and extinct apes, these taxa display derived craniodental and post-cranial characters suggesting that they are all cladistically hominid. Their phylogenetic relationships and locomotor capabilities are under active study and debate.
In contrast, the time-successive species Au. anamensis and Au. afarensis are widely interpreted as sampling an evolving lineage. All known Au. anamensis specimens date to between approx 3.9 and approx 4.2 Myr ago. The earliest definitive Au. afarensis is at Laetoli, approx 3.6 Myr ago. This younger chronospecies is known by partial skeletons, well-preserved skulls and even attributed footprints. In contrast, Au. anamensis was heretofore documented only from the Turkana basin, and represented there by a relatively small sample8.
We report here on newly recovered Pliocene fossils from the Middle Awash study area, Afar rift, Ethiopia. The Adgantole Member of the Sagantole Formation has yielded a hominid maxilla. Contemporary sediments exposed approximately 10 km to the west have yielded an additional 30 hominid specimens representing a minimum of eight individuals. Dated to approx 4.12 Myr ago and attributed to Au. anamensis, these remains extend the known range of this taxon by about 1,000 km to the northeast and extend the anatomical representation of early Australopithecus.
Snakes with legs - Yikes
Alfred Hitchcock was Right
Baby Australopithecus found