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The hipparions of the Baringo Basin sequence

Naturevolume 254pages211212 (1975) | Download Citation



THE first appearance of Hipparion in land mammal populations of the northern hemisphere is one of the best documented biochronological events of the Neogene: the genus appeared first in the Mediterranean world about 12.5 Myr ago1. In France2 its first appearance was during the Middle–Upper ‘Helvetian’ (ante-‘Tortonian’). New radiometric information from the Far East supports an age of 10.5 Myr for the base stratotype Tortonian1. This means that the Hipparion datum of 12.5 Myr is some 2 Myr earlier than the advent of the Vallesian.

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  1. Rijksmuseum van Natuurlijke Historie, Leiden, The Netherlands



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