Origin of the hominodea

Question 1

Raymond dart’s discovert

Answer 1

• 1925 Discovery of Taung boy
• Brain small but more human than ape
• Small human-like canine teeth
• Bipedal (foramen magnum central) located under skull when more bipedal

Question 2

How can you tell if an animal was bipedal from the skull morphology?

Answer 2

• foramen magnum central
• Located under skull when more bipedal

Question 3

What is the Foramen magnum central?

Answer 3

• Hole at the back of the skull that attaches to the spinal column
• When bipedal, hole is located underneath skull

Question 4

What are the robust and gracile forms of Australopithecus?

Answer 4

Robust: A.robustus (more heavily built)
Gracile: A.africanus

Question 5

Age of A.robustus?

Answer 5

2.0 - 1.0 Ma

Question 6

What are the major australopithecine sites?

Answer 6

• Limestone caves near Johanneberg
• Various other cave systems/sink holes across Africa
• Rift Valley

Question 7

What was the Young swartkran (australopithicine) specimen?

Answer 7

• Dragged into cave my leopard
• Teeth marks in skull
• Missing back of skull

Question 8

Leakey Family and fossil collectors

Question 9

when/where was A.boisei (robust) found

Answer 9

• Found in Olduvai Gorge in Tanzania in 1959
• Discovered by Mary Leakey
• 1.75 Ma
• Ridge on skull where large jaw muscles were attached showing they had a strong bite.

Question 10

1960-1963 Homo habilis. Why did this discovery cause controversy?

Answer 10

• Discovered by Leakey’s team
• Debated that it wasn’t a homo
• 1.75 Ma
• Upset the linear evolution of hominins
• Genus homo needed to be redefined
• Existed at the same time

Question 11

Homo and Australopithecines were around at the same time

Answer 11

• Different hominins coexisting
• Star wars bar scenario

Question 12

More A.boisei discovered

Answer 12

• In lake Turkana, Kenya
• 1969
• Rift valley
• Sedimentary piles in rocks
• Lake contracts and expands depending on climate (interglacial/glacial)

Question 13

A. afarensis: Lucy

Answer 13

• 1970
• Very well preserved - almost whole skeleton
• Small
• > 3 Ma

Question 14

A. afarensis Footprints

Answer 14

• Laetoli, Tanzania, 1978
• Volcano ash blanketed the ground
• Footprints preserved in ash
• Two sets next to eachother
• Can tell how they walked

Question 15

A. aethiopicus

Answer 15

• from Omo, Ethiopia
• 1980’s
• 2.6 Ma
• Large jaw muscles
• Robust

Question 16

How many accepted species of Australopithecenes are there?

Answer 16

14

Question 17

What is special about the rift valley?

Answer 17

• Perfect place for preservation
• Are there fossils everywhere that are just not conserved?
• Findings in Chad suggest this
• Is our thinking influenced by a huge bias in the fossil record?

Question 18

What were the Australopithecines and how did they live?

Answer 18

• Between 3-2 Ma in Africa at least 6 hominin species co-existed
• Either sharing the same habitat or occupying different habitats.
• They were either Australopithecines or Homo.
• They inhabited a mixture of environments: plains; mixed plains/woodland; forest; lake side.

Question 19

What do we know about the Australopithecines?

Answer 19

• Modified dentition
• Curved phalanges
• Orientation for arm - can have above head for a long time
• Arm can move around more
• Sexual dimorphism - height and weight differ between male and female

Question 20

How did Australopithecines walk?

Answer 20

• Bipedal
• Walked in a bent knee bent hip style
• Probably spent a lot of their time in trees

Question 21

What do the teeth of australopithecenes show about diet?

Answer 21

• Compare tooth ware between fossils and current animal diets
• Large jaw mucles on robust forms
• Robust ate roots etc

Question 22

Did Australopithecines use tools?

Answer 22

• Yes/maybe
• Tools have been found that are thought to have been before homo evolved
• Suggested that some Australopithecines used / made tools

Question 23

What is the oldest hominids species described?

Answer 23

• Sahelanthropus tchadenis
• 6 - 7 Ma (chad)