Final answer:
The 'black skull', or Paranthropus aethiopicus, was discovered in Ethiopia in 1967 and is estimated to be 2.5 million years old. Paranthropus boisei, discovered by Louis and Mary Leakey in the Eastern Rift Valley in 1959, has unique features indicative of strong chewing adaptations.
Step-by-step explanation:
The "black skull", known scientifically as Paranthropus aethiopicus, was discovered in Ethiopia in 1967 by a French expedition team led by Camille Arambourg and Yves Coppens. This species has been estimated to be about 2.5 million years old (MYA). The black skull falls between the robust and gracile australopithecines, showing characteristics of both lineages.
Additionally, Paranthropus boisei, another significant fossil discovery, was found by Louis and Mary Leakey in 1959 in the Eastern Rift Valley. It took the Leakeys about 30 years of searching before they found this first hominin fossil, indicating the persistence required in paleoanthropological research.
Paranthropus boisei is notable for its unique cranial features indicating strong masticatory adaptations and is often referred to as the hyper-robust hominin. It showcases a mohawk-like crest on the top of its skull for muscle attachments, a low or absent forehead, flat face, large jaws, and large muscle attachment sites, which were adapted for heavy chewing.
The discovery of these fossils plays a crucial role in understanding human evolution and provides insight into the diversity of hominins that once walked the earth. Radiometric dating and other indirect dating techniques help scientists determine the age of such finds and contribute to our understanding of timelines in prehistoric life.