Recent developmental studies demonstrate that early fossil hominins
possessed shorter growth periods than living humans, implying
disparate life histories. Analyses of incremental features in
teeth provide an accurate means of assessing the age at death of
developing dentitions, facilitating direct comparisons with fossil
and modern humans. It is currently unknown when and where the
prolonged modern human developmental condition originated.
Here, an application of x-ray synchrotron microtomography reveals
that an early Homo sapiens juvenile from Morocco dated at
160,000 years before present displays an equivalent degree of
tooth development to modern European children at the same age.
Crown formation times in the juvenile’s macrodont dentition are
higher than modern human mean values, whereas root development
is accelerated relative to modern humans but is less than
living apes and some fossil hominins. The juvenile from Jebel
Irhoud is currently the oldest-known member of Homo with a
developmental pattern (degree of eruption, developmental stage,
and crown formation time) that is more similar to modern H.
sapiens than to earlier members of Homo. This study also underscores
the continuing importance of North Africa for understanding
the origins of human anatomical and behavioral modernity.
Corresponding biological and cultural changes may have appeared
relatively late in the course of human evolution.
Pretty neat. I haven't read it yet though.