What is a robust hominin?

The “robust” australopiths are a group of hominins with large cheek teeth and strongly built jaws that lived alongside the earliest members of our own genus, Homo, approximately 2.5-1.4 million years ago.

What caused the speciation event leading to the robust forms of early hominins?

Environmental pressures have long been assumed to play a key role in hominin speciation and adaptation [6]. The savannah hypothesis implicates the long-term trend towards increased aridity and the expansion of the savannah as a major driver of hominin evolution [7]–[8].

What are the characteristics of hominins?

Some characteristics that have distinguished hominins from other primates, living and extinct, are their erect posture, bipedal locomotion, larger brains, and behavioral characteristics such as specialized tool use and, in some cases, communication through language.

What is the difference between gracile and robust hominin varieties?

The main difference between gracile and robust is that gracile species had smaller cheek teeth, pronounced prognathism, less flared cheeks, and no sagittal crest, but robust species had enormous cheek teeth, robust jaws and massive jaw muscles, sometimes anchored to a bony crest running along the top of the skull.

What features on the skull of a robust australopithecine is related to its ability to consume hard food resources?

Robust species like Paranthropus robustus had large teeth as well as a ridge on top of the skull, where strong chewing muscles attached. These features allowed individuals to crush and grind hard foods such as nuts, seeds, roots, and tubers in the back of the jaw; however, P.

What do distinctive traits of robust australopithecines include?

Distinctive traits of the robust australopithecines include: small front teeth and large back teeth.

Which characteristics were present in the earliest hominins?

The first human-like traits to appear in the hominin fossil record are bipedal walking and smaller, blunt canines. The oldest hominins currently known are Sahelanthropus tchadensis from Chad (Brunet et al. 2005) and Orrorin tugenensis from Kenya (Senut et al. 2001).

Which of the following two obligate features is a hominin defined as having?

A hominin is defined as having two obligate behaviors: bipedal locomotion and nonhoning chewing complex.

Are humans gracile or robust?

The postcranial skeleton of modern Homo sapiens is relatively gracile compared with other hominoids and earlier hominins. This gracility predisposes contemporary humans to osteoporosis and increased fracture risk.

What defines a hominin?

Hominin – the group consisting of modern humans, extinct human species and all our immediate ancestors (including members of the genera Homo, Australopithecus, Paranthropus and Ardipithecus).

Which characteristic do all hominins share quizlet?

Ape trait? true (to be classified as a hominin, the species must be bipedal. Along w/ Homo sapiens, hominins include all bipedal human ancestors since our split from the common ancestors w/ chimps.) All hominins are bipedal.

What is the difference between hominid and hominin?

A hominid is a member of the family Hominidae, the great apes: orangutans, gorillas, chimpanzees and humans. A hominine is a member of the subfamily Homininae: gorillas, chimpanzees, and humans (excludes orangutans). A hominin is a member of the tribe Hominini: chimpanzees and humans.

What does the large size of the robust australopithecine teeth and jaws tell us about their diet?

Environment and diet
There is evidence that the environment was becoming drier after about 1.5 million years ago. The powerful grinding teeth and jaws of these species suggest that they ate large amounts of tough vegetation. Tooth wear patterns suggest hard foods like seeds, nuts and roots were included in the diet.

What does the large size of the robust australopithecine teeth and jaws tell us about their diet quizlet?

They are called robust because of their larger faces and teeth, jaw, chewing muscles. This means they ate harder course foods. They have a similar body size to Gracile.

What are robust australopithecines also called?

In East Africa, robust australopithecines are also called. Paranthropus. The diversity of the hominins included increasingly specialized: diets.

Which of these characteristics differentiates modern humans from all other hominids?

Language, culture, tool use, brain size, and bipedalism have all been cited as traits that differentiate modern humans from other primate species.

What are the key human attributes that scientists use in identifying certain fossils as early hominins?

They had larger faces and jaws accompanied by pronounced sagittal crests (in the case of males). They also had much larger back teeth (premolars and molars) and smaller front ones (incisors) compared to gracile australopithecines and early humans who were alive at the same time.

What kind of environment did the earliest hominins probably live in?

it showed diversity in the hominid fossil record 3.5 mya. d. it probably lived in woodlands.

How did early humans adapt to their environment to survive?

A large brain, long legs, the ability to craft tools, and prolonged maturation periods were all thought to have evolved together at the start of the Homo lineage as African grasslands expanded and Earth’s climate became cooler and drier.

How did climate affect hominid development?

On longer time scales, hominins experienced large-scale shifts in temperature and precipitation that, in turn, caused vast changes in vegetation – shifts from grasslands and shrub lands to woodlands and forests, and also from cold to warm climates.