New fossils from Jebel Irhoud, Morocco and the pan-African origin of
Homo sapiens.
Abstract
Fossil evidence points to an African origin of Homo sapiens from a
group called either H. heidelbergensis or H. rhodesiensis. However,
the exact place and time of emergence of H. sapiens remain obscure
because the fossil record is scarce and the chronological age of many
key specimens remains uncertain. In particular, it is unclear whether
the present day ‘modern’ morphology rapidly emerged approximately 200
thousand years ago (ka) among earlier representatives of H. sapiens or
evolved gradually over the last 400 thousand years. Here we report
newly discovered human fossils from Jebel Irhoud, Morocco, and
interpret the affinities of the hominins from this site with other
archaic and recent human groups. We identified a mosaic of features
including facial, mandibular and dental morphology that aligns the
Jebel Irhoud material with early or recent anatomically modern humans
and more primitive neurocranial and endocranial morphology. In
combination with an age of 315±34 thousand years (as determined by
thermoluminescence dating), this evidence makes Jebel Irhoud the
oldest and richest African Middle Stone Age hominin site that
documents early stages of the H. sapiens clade in which key features
of modern morphology were established. Furthermore, it shows that the
evolutionary processes behind the emergence of H. sapiens involved the
whole African continent.
http://www.nature.com/nature/
The age of the hominin fossils from Jebel Irhoud, Morocco, and the
origins of the Middle Stone Age.
Abstract
The timing and location of the emergence of our species and of
associated behavioural changes are crucial for our understanding of
human evolution. The earliest fossil attributed to a modern form of
Homo sapiens comes from eastern Africa and is approximately 195
thousand years old, therefore the emergence of modern human biology is
commonly placed at around 200 thousand years ago. The earliest Middle
Stone Age assemblages come from eastern and southern Africa but date
much earlier. Here we report the ages, determined by
thermoluminescence dating, of fire-heated flint artefacts obtained
from new excavations at the Middle Stone Age site of Jebel Irhoud,
Morocco, which are directly associated with newly discovered remains
of H. sapiens. A weighted average age places these Middle Stone Age
artefacts and fossils at 315±34 thousand years ago. Support is
obtained through the recalculated uranium series with electron spin
resonance date of 286±32 thousand years ago for a tooth from the
Irhoud 3 hominin mandible. These ages are also consistent with the
faunal and microfaunal assemblages and almost double the previous age
estimates for the lower part of the deposits. The north African site
of Jebel Irhoud contains one of the earliest directly dated Middle
Stone Age assemblages, and its associated human remains are the oldest
reported for H. sapiens. The emergence of our species and of the
Middle Stone Age appear to be close in time, and these data suggest a
larger scale, potentially pan-African, origin for both.
http://www.nature.com/nature/
Pandora
Homo sapiens.
Abstract
Fossil evidence points to an African origin of Homo sapiens from a
group called either H. heidelbergensis or H. rhodesiensis. However,
the exact place and time of emergence of H. sapiens remain obscure
because the fossil record is scarce and the chronological age of many
key specimens remains uncertain. In particular, it is unclear whether
the present day ‘modern’ morphology rapidly emerged approximately 200
thousand years ago (ka) among earlier representatives of H. sapiens or
evolved gradually over the last 400 thousand years. Here we report
newly discovered human fossils from Jebel Irhoud, Morocco, and
interpret the affinities of the hominins from this site with other
archaic and recent human groups. We identified a mosaic of features
including facial, mandibular and dental morphology that aligns the
Jebel Irhoud material with early or recent anatomically modern humans
and more primitive neurocranial and endocranial morphology. In
combination with an age of 315±34 thousand years (as determined by
thermoluminescence dating), this evidence makes Jebel Irhoud the
oldest and richest African Middle Stone Age hominin site that
documents early stages of the H. sapiens clade in which key features
of modern morphology were established. Furthermore, it shows that the
evolutionary processes behind the emergence of H. sapiens involved the
whole African continent.
http://www.nature.com/nature/
The age of the hominin fossils from Jebel Irhoud, Morocco, and the
origins of the Middle Stone Age.
Abstract
The timing and location of the emergence of our species and of
associated behavioural changes are crucial for our understanding of
human evolution. The earliest fossil attributed to a modern form of
Homo sapiens comes from eastern Africa and is approximately 195
thousand years old, therefore the emergence of modern human biology is
commonly placed at around 200 thousand years ago. The earliest Middle
Stone Age assemblages come from eastern and southern Africa but date
much earlier. Here we report the ages, determined by
thermoluminescence dating, of fire-heated flint artefacts obtained
from new excavations at the Middle Stone Age site of Jebel Irhoud,
Morocco, which are directly associated with newly discovered remains
of H. sapiens. A weighted average age places these Middle Stone Age
artefacts and fossils at 315±34 thousand years ago. Support is
obtained through the recalculated uranium series with electron spin
resonance date of 286±32 thousand years ago for a tooth from the
Irhoud 3 hominin mandible. These ages are also consistent with the
faunal and microfaunal assemblages and almost double the previous age
estimates for the lower part of the deposits. The north African site
of Jebel Irhoud contains one of the earliest directly dated Middle
Stone Age assemblages, and its associated human remains are the oldest
reported for H. sapiens. The emergence of our species and of the
Middle Stone Age appear to be close in time, and these data suggest a
larger scale, potentially pan-African, origin for both.
http://www.nature.com/nature/
Pandora
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