Paranthropus robustus

Paranthropus robustus (abbreviated P. robustus) is an extinct species of early hominin. It is one of the robust australopithecines. 

P. robustus lived from about 1.8 to 1.2 million years ago. It co-existed with early species of Homo.

 Fossils 
All of the known fossils of P. robustus have come from the Cradle of Humankind in South Africa. The first were discovered in 1938. After this discovery, anthropologist Robert Broom created the genus Paranthropus and placed this species into it.

 Description 

 Size 
P. robustus walked on two feet. They were smaller than modern humans. On average, males may have been just 1.2 meters (3.9 feet) tall and weighed around 54 kg (119 pounds). Females may have been under 1 meter (3.3 feet) tall and weighed only 40 kg (88 pounds). This difference in sizes between males and females is called sexual dimorphism.

The species' average brain size was 530 cc. This is about the same size as a modern chimpanzee's brain.

 Tools 
P. robustus probably had the physical ability to make tools. However, scientists have not found any stone tools near P. robustus fossils. Still, studies suggest that they used bones as tools to dig in termite mounds for food. 

 Diet 
P. robustus had very heavy jaws and large teeth with thick enamel. They also had large cheekbones and chewing muscles. These adaptations made it possible for P. robustus to eat hard, fibrous foods like roots, tubers, nuts, and seeds. The species probably had a generalist diet and may have also eaten soft fruits, young leaves, insects, and/or meat. It would have gathered these things from its habitat of open woodland and savanna.

Recent fossil discoveries suggest that P. robustus may have evolved these more powerful chewing muscles to adapt to climate change. Very tough or hard foods would have still been plentiful even as the climate became cooler and drier. Being able to eat these foods improved P. robustus's chances of survival.

 Evolution 
P. robustus may have evolved from Australopithecus africanus. 

P. robustus is an "evolutionary dead end": it went extinct without ever evolving into a different species.

 Related pages 

 Human evolution
 Australopithecines
 Paleoanthropology

 References 

Category:Australopithecines