the expansion of the brain the expansion of the brain followed bipedalism. the expansion of the...
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The expansion of the The expansion of the brainbrain
The expansion of the brain followed The expansion of the brain followed bipedalism. bipedalism.
We suggest this because the We suggest this because the australopithecines were bipedal apes australopithecines were bipedal apes with brains only slightly bigger than with brains only slightly bigger than chimpanzees.chimpanzees.
The development of the brain became The development of the brain became possible when the hands became free.possible when the hands became free.
Higher intelligence led to tool makingHigher intelligence led to tool making
Expansion of the brainExpansion of the brain Australopithicines on the left had similar Australopithicines on the left had similar
sized brains to chimpanzees, Homo sized brains to chimpanzees, Homo Habilis on the right had a larger brain Habilis on the right had a larger brain and learned to make and use tools.and learned to make and use tools.
Expansion of the brainExpansion of the brain
Making tools required Making tools required learning and memory.learning and memory.
The expansion of the brain The expansion of the brain made this easier.made this easier.
The tools then became The tools then became more complex as the genus more complex as the genus evolved.evolved.
Oldowan ToolsOldowan Tools
Oldowan tools culture was Oldowan tools culture was probably made by Homo habilis probably made by Homo habilis dating back to about 2.6myodating back to about 2.6myo
They found river worn pebbles They found river worn pebbles and knocked off edges flakes and knocked off edges flakes from several edges.from several edges.
This would then leave a core This would then leave a core with a cutting edge.with a cutting edge.
The sharp flakes were useful in The sharp flakes were useful in cutting.cutting.
Oldowan ToolsOldowan Tools
Some tools were used to work wood, some Some tools were used to work wood, some to cut meat and others to cut reeds.to cut meat and others to cut reeds.
What advantages would this enable?What advantages would this enable? Large animals could have been butchered.Large animals could have been butchered. The cores may have been used for cracking The cores may have been used for cracking
bones to extract the marrow.bones to extract the marrow. Crushing tough plant food.Crushing tough plant food. Digging edible bulbs and roots.Digging edible bulbs and roots.
This will have allowed a wider diet then This will have allowed a wider diet then ever before.ever before.
Acheulian ToolsAcheulian Tools
These tools were made by Homo erectus, These tools were made by Homo erectus, Homo heidelbergensis and archaic Homo Homo heidelbergensis and archaic Homo sapiens.sapiens.
They had a classical ‘tear drop’ shape.They had a classical ‘tear drop’ shape. They had a ‘biface’ shape that bulges They had a ‘biface’ shape that bulges
outwards on both sides.outwards on both sides. It would have taken many more blows then It would have taken many more blows then
Oldowan tools to make Acheulian tools.Oldowan tools to make Acheulian tools. Oldowan and Acheulian tools are classified Oldowan and Acheulian tools are classified
as the lower Palaeolithic or ‘early stone age’.as the lower Palaeolithic or ‘early stone age’.
Acheulian ToolsAcheulian Tools
Mousterian ToolsMousterian Tools
Mousterian tools were trademark of Mousterian tools were trademark of Homo Neandathalensis.Homo Neandathalensis.
Mousterian tools were shaped from Mousterian tools were shaped from flakes themselves.flakes themselves.
They would prepare a core, and then They would prepare a core, and then smash the flint rock against itsmash the flint rock against it
This is known as the Levallois This is known as the Levallois methodmethod
They used the rock flint as it chipped They used the rock flint as it chipped in a predictable way.in a predictable way.
Mousterian ToolsMousterian Tools
Upper Palaeolithic ToolsUpper Palaeolithic Tools
Made by the modern Homo Sapiens and Made by the modern Homo Sapiens and the last of the Neanderthals about 35,000 the last of the Neanderthals about 35,000 years ago.years ago.
Finer workmanship using a technique Finer workmanship using a technique called the punch blade.called the punch blade.
Long, thin flakes were removed and shaped Long, thin flakes were removed and shaped into a large number of different tools.into a large number of different tools.
They used other materials such as bone, They used other materials such as bone, ivory and antler to produce fine tools such ivory and antler to produce fine tools such as needles.as needles.
Upper Palaeolithic toolsUpper Palaeolithic tools
Stone tools were more finely made Stone tools were more finely made with more cutting edge per kg of stone with more cutting edge per kg of stone used.used.
As well as using a variety of materials As well as using a variety of materials they also used a composite tools they also used a composite tools (combination of materials)(combination of materials) E.g. spearhead of stone and carved antler E.g. spearhead of stone and carved antler
to wooden handles, using thongs of skin to wooden handles, using thongs of skin and plant gum to hold it.and plant gum to hold it.
Upper Palaeolithic ToolsUpper Palaeolithic Tools
Homo habilis and Homo Homo habilis and Homo rudolfensisrudolfensis
Homo habilis remains were found in Homo habilis remains were found in Olduvai in 1959.Olduvai in 1959.
He had a small cranium and a small jaw He had a small cranium and a small jaw and teeth compared to australapithicines.and teeth compared to australapithicines.
In 1972 it was thought another species In 1972 it was thought another species was found (H. rudolfensis) which had a was found (H. rudolfensis) which had a larger cranium and larger jaw and teeth.larger cranium and larger jaw and teeth.
There is a debate as to whether Homo There is a debate as to whether Homo rudolfensis existed because some suggest rudolfensis existed because some suggest it was just a single sexual dimorphic it was just a single sexual dimorphic species of H. habilis.species of H. habilis.
Homo ErectusHomo Erectus
H. Erectus was the first pre-human to H. Erectus was the first pre-human to leave Africa.leave Africa.
Erectus was also the first known to use Erectus was also the first known to use fire!fire!
Some were found in Indonesia and China.Some were found in Indonesia and China. Some also have been found in East Africa Some also have been found in East Africa
which differ in a number of ways.which differ in a number of ways. Some people regard the Asian species to Some people regard the Asian species to
be called H. Ergaster because of these be called H. Ergaster because of these differences.differences.
Homo ErectusHomo Erectus
Evidence for the use of fire is the Evidence for the use of fire is the presence of charcoal and charred presence of charcoal and charred bones and thermally altered stones bones and thermally altered stones in a ring shape.in a ring shape.
It is not known whether H. erectus It is not known whether H. erectus could create fire but it is thought could create fire but it is thought that they maintained it when it that they maintained it when it occurred naturally (lightening).occurred naturally (lightening).
Homo erectusHomo erectus
What are some benefits of fire?What are some benefits of fire? Warmth – (ice ages)Warmth – (ice ages) Illumination at night – (tool making and Illumination at night – (tool making and
butchering)butchering) Predator protectionPredator protection Harden wooden spear pointsHarden wooden spear points Stampede animals into trapsStampede animals into traps CookingCooking Social organisation!Social organisation!
Homo heidelbergensisHomo heidelbergensis
Originally classified as archaic H. Originally classified as archaic H. sapiens until the early 1990’s when sapiens until the early 1990’s when well preserved remains of around 30 well preserved remains of around 30 adult and juvenile remains were adult and juvenile remains were found.found.
It is now believed that this species It is now believed that this species may have given rise to H. may have given rise to H. neanderthalensis neanderthalensis
They used the acheulian hand axes.They used the acheulian hand axes.
Homo neanderthalensisHomo neanderthalensis
The most recent pre-modern The most recent pre-modern humans.humans.
Found in Europe and western Asia.Found in Europe and western Asia. They had a slightly larger brain sizeThey had a slightly larger brain size Had a prominent occipital bun.Had a prominent occipital bun. Strong teeth and jaw.Strong teeth and jaw. Prominent brow ridgesProminent brow ridges Thick limb bones.Thick limb bones.
Homo neanderthalnesisHomo neanderthalnesis
There is evidence the cared for their There is evidence the cared for their elderly.elderly. Many intact skeletonsMany intact skeletons Bones sometimes covered with game Bones sometimes covered with game
animalsanimals Tools foundTools found Pollen grains of flowers have been found Pollen grains of flowers have been found
with skeletons.with skeletons. They used the mousterian tool culture.They used the mousterian tool culture.
Upper palaeolithic toolsUpper palaeolithic tools
Upper Upper Palaeolithic ArtPalaeolithic Art
The origin and spread of The origin and spread of modern Humansmodern Humans
The ‘regional continuity’ or candelabra The ‘regional continuity’ or candelabra hypothesis is a challenging model.hypothesis is a challenging model.
In this model humans evolved more or In this model humans evolved more or less simultaneously across the entire Old less simultaneously across the entire Old World from several ancestral populations.World from several ancestral populations.
In this model is suggest there was some In this model is suggest there was some ‘gene flow’ between the regions in order ‘gene flow’ between the regions in order for them to evolve at a similar rate.for them to evolve at a similar rate.
This suggests that ‘racial’ characteristics This suggests that ‘racial’ characteristics would be very ancient.would be very ancient.
Regional continuity Regional continuity hypothesishypothesis
Regional Continuity Regional Continuity HypothesisHypothesis
There are many criticisms of this theory.There are many criticisms of this theory. Some are…Some are… Molecular and genetic evidence suggest Molecular and genetic evidence suggest
evolution and then migration rather than evolution and then migration rather than evolution simultaneously in different evolution simultaneously in different continents.continents.
MtDNA suggest the Neanderthals were a MtDNA suggest the Neanderthals were a dead end species rather then evolving into dead end species rather then evolving into humans.humans.
It appears Neanderthals and modern It appears Neanderthals and modern humans co-existed and therefore wouldn’t humans co-existed and therefore wouldn’t have evolved into modern Europeans.have evolved into modern Europeans.
The Out of Africa The Out of Africa HypothesisHypothesis
Another more supported model is the Another more supported model is the ‘replacement’ or the ‘Out of Africa’ ‘replacement’ or the ‘Out of Africa’ hypothesis.hypothesis.
This suggested modern humans evolved This suggested modern humans evolved relatively recently in Africa before relatively recently in Africa before spreading to Asia and Europe to replace spreading to Asia and Europe to replace the existing, less advanced populations.the existing, less advanced populations.
This would suggest that racial This would suggest that racial characteristics would be relatively characteristics would be relatively recent.recent.
Out of Africa HypothesisOut of Africa Hypothesis
The matter is not finally resolved but this The matter is not finally resolved but this is one hypothesisis one hypothesis
Mitochondral DNA Mitochondral DNA evidenceevidence
Mitochondria are self replicating and have Mitochondria are self replicating and have their own DNA. their own DNA.
It is inherited only via females, so your It is inherited only via females, so your mtDNA is passed on from your mother, mtDNA is passed on from your mother, and hers from her mother and so on.and hers from her mother and so on.
This means in theory you can go back to This means in theory you can go back to one maternal ancestor.one maternal ancestor.
It also means that it will only change by It also means that it will only change by mutation (mtDNA mutates about 10 times mutation (mtDNA mutates about 10 times that of nuclear DNA because it doesn’t that of nuclear DNA because it doesn’t have the proof reading mechanisms that have the proof reading mechanisms that nuclear DNA has).nuclear DNA has).
Mitochondral DNAMitochondral DNA
When mtDNA was compared from When mtDNA was compared from different human populations they found different human populations they found people from the same ethnic group people from the same ethnic group showed fewer differences than people of showed fewer differences than people of different ethnic groups.different ethnic groups.
They then used the differences to They then used the differences to measure the relatedness and measure the relatedness and constructed an evolutionary tree from constructed an evolutionary tree from ‘restriction maps’.‘restriction maps’.
It had two main branches, one leading It had two main branches, one leading to Africans and the other to Asians, to Africans and the other to Asians, Europeans, and native Australians.Europeans, and native Australians.
Mitochondral DNA Mitochondral DNA evidenceevidence
Migration out of AfricaMigration out of Africa It is thought that modern humans inhabited east Asia It is thought that modern humans inhabited east Asia
around 67,000 years ago and Australia around 50,000 around 67,000 years ago and Australia around 50,000 years ago.years ago.
Why did modern humans appear in Europe only Why did modern humans appear in Europe only 40,000 years ago considering it is so close to Africa?40,000 years ago considering it is so close to Africa?
Modern humans migrated to other parts of the world Modern humans migrated to other parts of the world in an ice age where they were able to cross easily.in an ice age where they were able to cross easily.
To get to Europe they will have encountered ice To get to Europe they will have encountered ice shelves such as the Southern Elps making this more shelves such as the Southern Elps making this more difficult.difficult.
It is thought the crossed to America between 30 and It is thought the crossed to America between 30 and 15 thousand years ago when there was a temporary 15 thousand years ago when there was a temporary ice-age land bridge.ice-age land bridge.
AfricaAfrica
DomesticationDomestication
How do we know whether and animal or How do we know whether and animal or plant is wild or domesticated?plant is wild or domesticated?
When something becomes domesticated, When something becomes domesticated, selection then becomes a factor, and the selection then becomes a factor, and the characteristics of it will change.characteristics of it will change. E.g. tusk size in pigs has decreasedE.g. tusk size in pigs has decreased Wild barley grains are in two rows on the central Wild barley grains are in two rows on the central
axis, whilst cultivated barley are in six rows.axis, whilst cultivated barley are in six rows. Animals killed by hunting are of various Animals killed by hunting are of various
ages compared to those killed under ages compared to those killed under domestication which are usually young domestication which are usually young adults.adults.
Domestication of Domestication of AnimalsAnimals
Advantages: Advantages: Source of milk or hair providing a steady Source of milk or hair providing a steady
supply of food and material.supply of food and material. If the animal is alive, the meat won’t If the animal is alive, the meat won’t
decay.decay. It may be killed at the It may be killed at the
optimum age.optimum age. Used to carry and lift Used to carry and lift
lowering energylowering energyexpenditure.expenditure.
Domestication of Domestication of AnimalsAnimals
Disadvantages:Disadvantages: Diseases that affect modern humans Diseases that affect modern humans
were originally caught by domesticated were originally caught by domesticated animals.animals. E.g. smallpox, measles and tuberculosis are E.g. smallpox, measles and tuberculosis are
probably from cattle.probably from cattle. Resistance is slowly developing in Eurasian Resistance is slowly developing in Eurasian
populations but Maori had no resistance populations but Maori had no resistance when these diseases were introduced by when these diseases were introduced by Europeans.Europeans.
Domestication of PlantsDomestication of Plants
Advantages:Advantages: Large surpluses could have been built Large surpluses could have been built
up and used to trade for raw materials up and used to trade for raw materials for tool making (e.g. obsidian).for tool making (e.g. obsidian).
Disadvantages:Disadvantages: Surpluses accumulated after harvest Surpluses accumulated after harvest
and attracted insects and rodents.and attracted insects and rodents. Single species crops were more Single species crops were more
vulnerable to disease such as fungi.vulnerable to disease such as fungi.
Social ConsequencesSocial Consequences
Moving from food gathering to food Moving from food gathering to food production may have led to production may have led to establishment of permanent establishment of permanent settlements.settlements.
They would build larger and more They would build larger and more permanent dwellingspermanent dwellings
The necessity to carry material around The necessity to carry material around got less so they had time to develop got less so they had time to develop more specialised tools such as pottery.more specialised tools such as pottery.
Social ConsequencesSocial Consequences
With a food surplus, not everyone With a food surplus, not everyone needed to produce food and could trade needed to produce food and could trade services such as carpenters, merchants services such as carpenters, merchants and priests.and priests.
This spawned a development of social This spawned a development of social complexity known as the ‘Neolithic complexity known as the ‘Neolithic Revolution’.Revolution’.
Crop planting was seasonal and Crop planting was seasonal and therefore may have led to astronomy and therefore may have led to astronomy and the keeping of the calendar.the keeping of the calendar.