Mario Petrinovic wrote:
https://www.sciencedaily.com/releases/2024/05/240501091650.htm
And then everybody will use molecular clock, which isn't
accurate at all, actually, it is always wrong, but it has one
advancement, you can adjust it the way you like it. My god, science is
such a joke.
The paper is public and explains things better.
https://www.nature.com/articles/s41467-024-47787-3
New Late Pleistocene age for the Homo sapiens
skeleton from Liujiang southern China
29 April 2024
Abstract
The emergence of Homo sapiens in Eastern Asia
is a topic of significant research interest.
However, well-preserved human fossils in secure,
dateable contexts in this region are extremely
rare, and often the subject of intense debate
owing to stratigraphic and geochronological
problems. Tongtianyan cave, in Liujiang
District of Liuzhou City, southern China is one
of the most important fossils finds of H.
sapiens, though its age has been debated, with
chronometric dates ranging from the late Middle
Pleistocene to the early Late Pleistocene. Here
we provide new age estimates and revised
provenience information for the Liujiang human
fossils, which represent one of the most
complete fossil skeletons of H. sapiens in
China. U-series dating on the human fossils and
radiocarbon and optically stimulated
luminescence dating on the fossil-bearing
sediments provided ages ranging from ~33,000 to
23,000 years ago (ka). The revised age estimates
correspond with the dates of other human fossils
in northern China, at Tianyuan Cave
(~40.8–38.1 ka) and Zhoukoudian Upper Cave
(39.0–36.3 ka), indicating the geographically
widespread presence of H. sapiens across Eastern
Asia in the Late Pleistocene, which is
significant for better understanding human
dispersals and adaptations in the region.
"The Liujiang materials were originally
recovered in September 1958, in a cave
called Tongtianyan by workmen digging for
phosphorous fertilizer..."
Less than a decade after the 1949 revolution
and possibly not the best of times for science
pursuits. AND the site was chewed up by workers
after fertilizer components. Yikes. Definitely
not promising.
"Since the discovery of the hominin fossils,
two independent radiometric dating projects
have been conducted. Using conventional
radiocarbon and classic α-counting U-series
dating methods, Yuan and colleagues obtained
a 14C age of 3.0 ± 0.2 ka cal BP for the
flowstone near the cave entrance, a U-series
age of 67 + 6/−5 ka for the thick flowstone on
top of Unit II (see Supplementary Information,
section 1.2), and U-series ages ranging between
227 and 95 ka for the mammalian fossils. The
investigators suggested that the human fossils
were older than ~67 ka, but they noted that this
age estimate remained to be verified given the
uncertain provenience of the finds. A later
attempt to establish the age of the Liujiang
deposits was by Shen and colleagues14,16 using
α-counting and thermal ionization mass
spectrometry U-series methods to date the
flowstones from various depositional units
and mammalian fossils. The researchers
concluded that the human fossils dated to at
least ~68 ka and more likely to ~139–111 ka if
they came from the refilling breccia. ..."
Morphological comparisions did come close to the
new revised dates but radiometric dating is
preferred.
According to the references those earlier
radiometric dating efforts were in 1986, 2002,
and 2004. Looks like they were taking the
dating of the layers and faunal remains as being
applicable to the hominid fossils. This is
usually a reliable way to do things but as noted,
this should probably be considered a disturbed
site thanks to those fertilizer hunters.
"Tongtianyan cave has long been seen as a
site demonstrating the co-existence of H.
sapiens alongside Ailuropoda-Stegodon
fauna during the Late Pleistocene of south
China, reinforcing evidence for the deep
antiquity of the human fossils. Previous
U-series dating of seven fossil teeth ranged
from 227 to 95 ka. We collected eight
mammalian fossil teeth for U-series dating
to test this relationship. ... disturbed
sediments as a consequence of digging for
fertilizer ... However, the human fossils
were distinct from the mammalian fauna in
terms of U-series isotopic ratios and
apparent U-series ages (Fig. 5c), indicating
that there is no association between the
human fossils and the Ailuropoda-Stegodon
fauna."
This new paper represents a more meticulous
effort to pin things down.
"In sum, provenience and dating studies have
been conducted on the flowstone, sediments
and the human and mammalian fossil remains.
Our proveniencing results indicate that the
Liujiang human fossils derived from Layer 2
of Unit III. Layer 2 ranged from 32.5 ± 2.5 to
22.6 ± 7.4 ka using Bayesian analysis on
radiocarbon, OSL and carbonate U-series ages.
U-series dating on the human fossils provided
a minimum age of 23.9 ± 0.5 ka, falling into
the age range for Layer 2. Collectively, the
age of the Liujiang human fossils can be
constrained to ~33–23 ka. The mammalian fossils
dated to between 227 ka and 95 ka by U-series
methods indicate a significant hiatus between
the deposition of the Ailuropoda-Stegodon fauna
and the human remains."
If only someone had found that site before
workmen chewed things up this would have been
resolved a long time ago.
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