A multi-disciplinary seriation of early Homo and Paranthropus bearing palaeocaves in southern Africa

Fossils of early Homo and Paranthropus have been recovered from several sites in southern Africa. Unfortunately, their precise age has historically been difficult to assess, hampering the reconstruction of their relationships to each other and to fossils from eastern Africa. Multi-dating strategies combining biochronological, archaeological, palaeomagnetic, electron spin resonance (ESR) and uranium series techniques are now clarifying their age. The following sequencing of sites is suggested: Swartkrans Member 1 (∼2.0 Ma), Gondolin (∼1.8 Ma), Kromdraai (1.8–1.7 Ma), Sterkfontein M5A (1.8–1.4 Ma), Swartkrans M2 (1.7–1.1 Ma), Sterkfontein M5B (1.4–1.1 Ma), Sterkfontein M5C (1.3–0.8 Ma), Swartkrans M3 (∼1.0–0.6 Ma). The position of Coopers D and Drimolen is difficult to access because they only have faunal age ranges (1.9–1.6 Ma). ESR suggests mixing is a potential major problem in multi-generational sites. The oldest southern African representatives of early Homo and Paranthropus occur around 2.1–1.9 Ma in Swartkrans Member 1 and are recorded almost continuously in the palaeocave deposits until around 1.0–0.6 Ma in Swartkrans Member 3. Currently, these data suggest that Paranthropus and Homo first occur significantly later in the southern African record than the eastern African record. Moreover, Paranthropus persists much later in southern Africa than in eastern Africa.