Brain evolution in the fossil record

Question 1

describe the Australopithecines

Answer 1

earliest hominins, 3-4 MYA, walked up right, strong arms for tree climbing, small brains

Question 2

what are the oldest known tools

Answer 2

Oldowans

Question 3

describe the Oldowan

Answer 3

rock with sharp edges called “choppers”, used for cutting, scraping etc

Question 4

when did Homo habilis live and how do they compare to Australopithecines

Answer 4

about 2-1 MYA ago, increased body size, slightly larger brains

Question 5

when did homo erectus live and what did they do

Answer 5

1.89 to 110,000 year ago, may be the first hominid species to have controlled fire

Question 6

what is acheulian technology

Answer 6

1.6 - 200,000 ya, used by erectus and neanderthals, flanked stones hand axes with sharp point used for cutting meat, wood, plants and digging

Question 7

who were the homo neanderthals

Answer 7

closest relatives, overlap with humans 400,000 - 40,000 ya, adapted to live in cold climates, hunted, buried dead and used tools, possibly used language

Question 8

what is mousterian technology

Answer 8

used by neanderthals and humans, small hand axes made from stone-knapping method called levallois, allowed greater control

Question 9

what happened during the upper palaeolithic revolution

Answer 9

variety of tools, long distance transport of materialism elaborate shelter burial and art

Question 10

what is paleoneurology

Answer 10

using hard tissue of the skull to infer the soft tissue anatomy

Question 11

what are endocasts

Answer 11

cast on the inside of brain cavity functioning as a proxy for the endocranium

Question 12

what are the limitation of endocast approach

Answer 12

small sample size, scarce and fragmented fossil record, large individual variation, preservation of individual endocranial areas are not homogeneous

Question 13

what data do we get from endocasts

Answer 13

Brain size (overall and relative if we know the body size), surface morphology

Question 14

what was the lunate sulcus debate

Answer 14

Holloway suggests the lunate sulcus was located more posteriorly in Australopithecus than in chimpanzees suggesting early re-organization of posterior regions before brain evolved, Falk suggests the posterior area he was observing was not actually the lunate sulcus but instead the lambdoid suture

Question 15

what are the main conclusion made from studying the fossil record

Answer 15

increase in brain size during human evolution, internal reorganisation of the brain