Lecture 15 - evolution of modern humans

Question 1

what big effect do the glacial cycles have?

Answer 1

• the sea levels vary significantly depending on whether glacias have expanded out or contracted
  expanded = reduced levels
  contracted = raised levels

Question 2

how did people first migrate to australia?

Answer 2

• requires island hopping even though the gap between the islands and Australia was much more reduced than it is now
• longest boat trip to be made was 52 miles

Question 3

what do glacial events tell us about the migrations that could have happened to populate homo sapiens in Australia and America?

Answer 3

the glacial event lowered sea levels to expose the shallow continental shelf - left a corridor linking north America and Siberia and narrowing the gap between the islands and Australia facilitating migrations

Question 4

when was it thought that people first went to Australia and why?

Answer 4

about 50,000 years ago - debate over whether they went out intentionally looking for it or is they got blown unintentionally of course when fishing etc

Question 5

what do paleovegetation reconstructions tell us about Australia?

Answer 5

• the environment used to be very different to what it is now
  e. g. savannah joined australia and new guinea on the continental shelf

Question 6

what was it believed Europeans found when they rediscovered Australia?

Answer 6

two main groups
1 had come down from china/ eastern asia
1 from a more western area down
this was entirely based on anatomy

Question 7

what is now thought about the people that invaded Australia?

Answer 7

now know that anatomical comparisons are less robust because on intraspecific variation - now thought there was just one invasion but possibly several waves

Question 8

what is ‘mungo man’ ?

Answer 8

homo sapien (50ka) found in burials in Australia 
- australians also had the first cremations - pots found with ash in

Question 9

what evidence do we have of just one group that invaded australia?

Answer 9

Evidence from archaeology

Evidence from molecular biology

Megafauna- alot of megafauna is often wiped out when humans first arrive

Evidence from anatomy is now discredited

Question 10

what is more evidence for aggression in early humans?

Answer 10

pattern of evidence that when h.sapiens invade a place they wipe out any existing humans and megafauna

Question 11

how did humans invade the americas?

Answer 11

invaded across beringia when it was land between siberia and alaska
- was thought they followed mammoths

Question 12

how is it thought they invaded south america?

Answer 12

used the coast as a guide because evidence suggested they spread through south america very quickly and it would have been very difficult to battle through the rainforests

Question 13

when is it thought the americas were invaded and describe the population numbers?

Answer 13

now generally considered the americas was invaded about 30,000 yrs ago . in low population numbers - spread throughout the whole of north and south america
- then there was cultural increase in population numbers when clovis culture appears (form of tools)

Question 14

describe archaelogical evidence for the america model?

Answer 14

• bones, rock shelters, tools (prodominantly clovis but some odd ones have been found which are much older so the model has changed slightly in recent years

Question 15

describe anatomical evidence for the americas model?

Answer 15

• alot of distinctive tribes around the americas - in general quite good evidence that people came from the north as they were well adapted for the cold e.g. short and stocky
• main idea = a few waves through beringia and then a population explosion linked to clovis culture

Question 16

describe evidence of language in the americas model?

Answer 16

• cladistic analysis of language and look at basal words that have changed and so on

Question 17

describe what evidence megafauna shows for the americas model?

Answer 17

all wiped out when humans first moved in - is thought in africa humans evolved in tandem with the megafauna and then when the humans moved out and came into contact with new fauna they were more scared and destroyed it
- is why africa is one of the only places you still find megafauna

Question 18

evolution and migrations require a larger brain size - what is brain expansion related to?

Answer 18

mother’s metabolic rate

gestation time and litter size

Question 19

what are the problems with a big brain?

Answer 19

• requires stable, high energy food supply
• birth problems - larger heads are harder to fit through a birthing canal - so brain and skull have to be born not fully developed therefore length of pregnancy is artificially reduced which results in an extended childhood which needs more division of labour as mothers are out of action for longer

Question 20

describe the brain sizes of early homo species

Answer 20

Australopethicine -400cc (EQ 2.5)
H. rudolphensis/habilis 650-800cc (EQ 3.1)
H. ergaster/erectus 850-1000cc (EQ 3.3)
Archaic H. sapiens 1000-1400cc (EQ 5.5)

Question 21

speech/language is related to brain size - what is evidence for speech?

Answer 21

• Endocasts of the brain (know the parts of the brain that habe been developed for speech in modern humans and see if they are expanded)
• Larynx/pharynx structure ( n humans babies have a modified pharynx which is similar to chimps - it stops them from choking but prevent speech - loose when they get older)
• Tongue nerve hole (lots of nerves in tongue to use it for speech)
• Spinal canal (gets bigger with speech )
• Tools, art etc (need to be able to conceptualise things )
• FOXP2 gene (if its damaged people cant speak - trace back homologs of this gene in the great apes when they diverged)
  Overall speech is not a bery satisfactory area of study - difficult to come to conslusions

Question 22

what evidence do we have of art?

Answer 22

• Ochre found from 100,000 from South Africa (used for painting or painting bodies)
• Paintings in caves from 33,500-10,000- Reported from Europe (but also China and South Africa - very little human representation mainly animals - stopped about 10,000 yrs ago when the ice retreats

Question 23

what is it thought the carvings of figurines from 35,000 yrs ago represent?

Answer 23

fertility symbols - found all over the place - either they are converging or the technology spread

Question 24

describe the Sungir man found in russia (28-30ka)

Answer 24

found in a burial with 2936 ivory beads (probably adorning clothes)
- shows they must have had time on their hands - complex societies

Question 25

describe the timeline of creativity?

Answer 25

• 100,000 Jewelry (shell beads) from the Levant and North Africa
• 40,000 Flutes (music) discovered in Europe
• 30,000 Wild flax used (?to manufacture clothing)
• 20,000 Pottery

Question 26

How did early humans transfer from being hunter-gatherers

Answer 26

• learnt how to grow their own food and take animals for use
• Mese-America : Maize , Squash , Cotton (9000 yrs ago)
• China : rice, miller, soybean, pigs (7000 yrs ago)
• Plant and animal domestication occurred independently and at different times in many different parts of the world

Question 27

in how many places did animal+plant domestication occur

Answer 27

• three major centres of origin existed, influence spread geographically , eventually coming to dominate local innovations
• with domestication came settlements - requirement to stay in one place

Question 28

when did the agricultural (neolithic) revolution start

Answer 28

• 12,000 KA

Question 29

what happens following the agricultural revolution

Answer 29

• population explodes from 10 million to 100 million (neolithic supernova)

Question 30

what example records a transition from hunter-gatherers to farmers

Answer 30

Abu Huregre (syria) is a series of villages continuously occupied from 13,000 to 9,500 and records a transition from hunter- gatherers to farmers.

Question 31

when was the earliest walled city

Answer 31

Jericho (trading post) 10,000 years ago

Question 32

when did the bronze age begin

Answer 32

5300 years ago