The cradle of mankind

The system of rift valleys that characterizes the African continent represents a perfect environment to understand the evolution of mankind; for the important paleoanthropological discoveries in Ethiopia, Kenya, Tanzania, Uganda and Zaire, the African rift valley system is indeed considered the “cradle of mankind”, that is the place where our species evolved and diversified in the last million years.
The association between paleoanthropological discoveries and rift valleys is not accidental, since the volcanic and tectonic activities that gave rise to the tectonic depressions and the contemporaneous accumulation of sediments in the basins created the ideal conditions for the proliferation of life. In parallel, lavas, volcaniclastic sediments, and tephra were responsible for the quick burial and preservation of faunal and floral remains.

Many extremely well-preserved human and animal fossils have been found in the Ethiopian rift valley, suggesting that this area may have represented a crucial site for human evolution in the last million years. In particular, some Ethiopian localities are of great importance for paleoanthropological researches: for instance, fossils from the Middle Valley of the Awash river bear witness of the whole hominid evolution, from 6 million years to the present.

In particular, the Afar triangle has yielded an abundance of vertebrate fossils, with some of the richest deposits of the early hominins of Africa. These include remains of Australopithecus afarensis, with the famous partial skeleton named Lucy found by Donald Johanson and colleagues at Hadar in the Awash Valley

Recent findings (see summary here) reveal a diversity of hominin species in the Afar region during the Pliocene, suggesting a hominin fossil record more diverse than previously known. In particular, as many as four hominin lineages coexisted in eastern Africa between 3.0 and 2.5 million years ago, highlighting a complex evolution towards moden humans.