Cosmogenic nuclide dating of Australopithecus at Sterkfontein, South Africa Darryl E Granger cs 2022
PNAS 119 (27) e2123516119
doi org/10.1073/pnas.2123516119
Cosmogenic nuclide dating of Australopithecus at Sterkfontein, South Africa Darryl E Granger cs 2022
PNAS 119 (27) e2123516119
doi org/10.1073/pnas.2123516119
The REAL text, not what you made up
... "savanna" ...
littor...@gmail.com wrote:
Cosmogenic nuclide dating of Australopithecus at Sterkfontein, South AfricaThe REAL text, not what you made up
Darryl E Granger cs 2022
PNAS 119 (27) e2123516119
doi org/10.1073/pnas.2123516119
https://www.pnas.org/doi/epdf/10.1073/pnas.2123516119
Significance
Australopithecus fossils from the richest hominin-bearing deposit (Member 4) at Sterkfontein in South Africa are considerably older than previously argued
by some and are contemporary with Australopithecus afarensis in East Africa. Our dates demonstrate the limitations of the widely accepted concept that Australopithecus africanus, which is well represented at Sterkfontein, descended from A. afarensis. The contemporaneity of the two species now suggests that a more complex family tree prevailed early in the human evolutionary process. The dates highlight the limitations of faunal age estimates
previously relied upon for the South African sites. They further
demonstrate the
importance of detailed stratigraphic analysis in assessments of accurate dating
of the karst cave sites in South Africa, which are stratigraphically
highly complex.
Abstract
Sterkfontein is the most prolific single source of Australopithecus
fossils, the vast
majority of which were recovered from Member 4, a cave breccia now exposed by erosion and weathering at the landscape surface. A few other Australopithecus
fossils, including the StW 573 skeleton, come from subterranean deposits
[T. C.
Partridge et al., Science 300, 607–612 (2003); R. J. Clarke, K. Kuman,
J. Hum. Evol. 134, 102634 (2019)]. Here, we report a cosmogenic nuclide isochron
burial date of 3.41 ± 0.11 million years (My) within the lower middle part of
Member 4, and simple burial dates of 3.49 ± 0.19 My in the upper middle part
of Member 4 and 3.61 ± 0.09 My in Jacovec Cavern. Together with a previously
published isochron burial date of 3.67 ± 0.16 My for StW 573 [D. E.
Granger et al.,
Nature 522, 85–88 (2015)], these results place nearly the entire Australopithecus assemblage at Sterkfontein in the mid-Pliocene, contemporaneous with
Australopithecus afarensis in East Africa. Our ages for the fossil-bearing breccia in
Member 4 are considerably older than the previous ages of ca. 2.1 to 2.6 My interpreted from flowstones associated with the same deposit. We show that these previously dated flowstones are stratigraphically intrusive within Member 4
and that they therefore underestimate the true age of the fossils.
"Ecological reconstructions from the Member 4 fauna indicate a climate more humid than today, with mosaic grassland, savanna, and gallery forest, consistent withForest.
both C3 and C4 diets determined from fossil teeth (49). The Member 5 fauna is
associated with a drying climate and far more grazers (49). "
"savanna"
Op woensdag 29 juni 2022 om 07:30:19 UTC+2 schreef Primum Sapienti:
Cosmogenic nuclide dating of Australopithecus at Sterkfontein, South Africa >>> Darryl E Granger cs 2022
PNAS 119 (27) e2123516119
doi org/10.1073/pnas.2123516119
The REAL text, not what you made up
... "savanna" ...
:-DDD
My little boy, you're the most idiotic of the kudu runners...
Do you understand the word "flow-stones"??
But the importance of this paper is that africanus did not evolve from afarensis, as anthropocentric PAs (kudu runners) like to believe.
IOW, Pliocene "gracile" afarensis & africanus (aquarboreal) evolved in // to early-Pleistocene "robust" boisei resp. robustus.
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