The Middle Awash research project has recovered the remains of fossil hominids spanning the last six million years.  From oldest to youngest ("Ma" means millions of years) these are:

•  5.2-5.8 Ma.  Ardipithecus kadabba is one of the earliest known hominids, from the Late Miocene.  It was first announced in 2001, and further remains were announced in 2004.

•  4.4 Ma.  Ardipithecus ramidus was first recognized as a new genus and species from the Middle Awash in 1994 and 1995.

•  4.1 Ma.  The species Australopithecus anamensis is widely considered to be the ancestor of Au. afarensis.  It has been found in the Middle Awash study area at upper Aramis and at Asa Issie, announced in 2006.

•  3.4 Ma.  Australopithecus afarensis (the "Lucy" species), was named for the Afar region and people in 1978, three years before the Middle Awash project was initiated.  Discoveries of this species made in the Middle Awash at Maka were announced in 1981 and 1993.

•  2.5 Ma.  Australopithecus garhi is another species first recognized in the Middle Awash and found in sediments containing the first evidence for butchery of large mammals with stone tools.  It was announced in 1999.

•  1.0 Ma.  Homo erectus is a species known from across the Old World.  Remains of this handaxe-maker were found at Bouri in the Middle Awash and announced in 2002.       

•  0.16 Ma (160,000 years).  The solidly dated and anatomically distinctive evidence of Homo sapiens was recovered from the Herto Bouri area and first announced as a subspecies "idaltu" in 2003.