Hominins you should be familiar with...
Sahelanthropus tchadensis |
Orrorin tugenensis |
Australopithecus afarensis |
Australopithecus africanus |
Homo habilis |
Homo erectus |
Homo heidelbergensis |
Homo neanderthalensis |
Homo sapiens |
Orrorin tugenensis
Dated back to around 6.1 - 5.8 million years ago
Said to be the first individual on the separate line from chimps.
Lived in Africa.
Brain size is unknown as a skull has never been found.
Is thought to be able to walk upright due to size and shape of femur.
Lived in Africa.
Brain size is unknown as a skull has never been found.
Is thought to be able to walk upright due to size and shape of femur.
Australopithecus afarensis (Lucy)
Dated back to around 4 - 3 million years ago
Said to be the first individual on the separate line from chimps.
Lived in Africa.
Brain size is approx. 445cc.
Lived in Africa.
Brain size is approx. 445cc.
- Is thought to have been bipedal due to locking knee socket.
- Shoulder joints suggest that they were also able to live in the trees.
- Large jaw, large zygomatic arch, significant prognathism - reflects vegetative diet.
- Larger brain than previous ancestor - perhaps more aware of surroundings?
- Pelvis is more human-like than chimp-like.
Australopithecus africanus
Dated back to around 3 - 2 million years ago
Slightly more evolved than Australopithecus afarensis.
Lived in Africa.
Brain size is approx. 500cc.
Lived in Africa.
Brain size is approx. 500cc.
- Very likely to be bipedal (evidence from the pelvis, femur and foot bones).
- Also thought to be very good at climbing trees (shoulder and hand bones suggest this).
- Larger brain than A. afarensis - evidence from a more prominant occipital bun.
- Smaller teeth than A. afarensis and a reduced zygomatic arch and jaw - signifies a change in diet.
Homo habilis (Handy man)
Dated back to around 2.4 - 1.4 million years ago
First species of the genus Homo.
Lived in Africa.
Brain size is approx. 600cc.
Lived in Africa.
Brain size is approx. 600cc.
- First tool makers - manufacturers of Oldowan tools.
- Larger brain - able to come up with uses for tools - tools gave access to new sources of food (i.e. bone marrow).
- Reduced prognathism, smaller jaw and teeth, smaller zygomatic arch - suggests less 'tough' diet (result of change in diet due to tools, scavenger behaviour).
Homo erectus
Dated back to around 1.8 million years ago - 145,000 years ago
Originated in Africa but remains have been found in Java, China, Georgia as well as in Africa.
Homo ergaster is the original species, and remained in Africa. Those that journeyed out are called Homo erectus.
Species has lived the longest time out of all Homo species.
Brain size is approx. 1000cc.
Homo ergaster is the original species, and remained in Africa. Those that journeyed out are called Homo erectus.
Species has lived the longest time out of all Homo species.
Brain size is approx. 1000cc.
- Developed more complex tools - manufacturers of Acheulean tools.
- Larger brain - able to come up with better techniques for making tools, and more uses for them.
- Harnessed fire, created fire, used fire - more likely to survive.
- Able to cook food, resulted in further reduction in prognathism, smaller jaw and teeth, smaller zygomatic arch.
- Biologically well-suited for bipedalism, able to run for long distances - can hunt for food and travel longer distances (allowing them to leave Africa). The group that stayed in Africa evolved into a different species - Homo ergaster.
- Greater social culture which supports babies with bigger brains (they need more care).
Homo heidelbergensis
Dated back to around 700,000 - 200,000 years ago
Thought to be the common ancestor of modern humans and Neanderthals.
Fossils found in Africa and Europe.
Brain size is approx. 1200cc.
Fossils found in Africa and Europe.
Brain size is approx. 1200cc.
- Quite large in body and brain size.
- Capable hunter - routinely hunted large animals.
- Lilkely the first early human species to live in such a cold climate (Europe) - body shape suggests heat was able to be conserved easily.
- First hominin group to build shelters (using wood and rock).
Homo neanderthalensis (Neanderthals)
Dated back to around 400,000 - 30,000 years ago
Not an ancestor of Homo sapiens - thought to share a common ancestor with them (ancestor is H. heidelbergensis).
Lived in Europe and middle/southwestern Asia.
Brain size is approx. 1400cc.
Lived in Europe and middle/southwestern Asia.
Brain size is approx. 1400cc.
- Larger brain than humans (but proportionate to body) - does not mean they were 'smarter'.
- Stocky body helped to survive cold climate - also had a large nose to humidify and warm the cold/dry air present.
- Made and used sophisticated tools - Mousterian tools.
- Wore clothes, created art, buried their dead.
Homo sapiens
Dated back to around 200,000 years ago and still existing!
Not an ancestor of Homo neanderthalensis - thought to share a common ancestor with them (ancestor is H. heidelbergensis).
Lives all over the world.
Brain size is approx. 1350cc.
Lives all over the world.
Brain size is approx. 1350cc.
- Complex technology - Upper paleolithic tools.
- Dispersed across the world - able to adapt to many different climated due to intelligence and ability to make fires, clothes, etc.
- Developed agriculture, complex language, communities.
Evidence found that guides the predicted theories of human evolution
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1. Fossils and dating
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2. DNA analysis
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When an organism dies, often its body may decompose or be eaten by scavengers. However, sometimes the body is lucky enough to end up in the mud, river sediment, buried under ash, etc. where can be preserved. When hominins began burying bodies of the dead, this was very helpful for us as many bodies were preserved and able to be analyzed!
When a fossil is formed the hard parts of the dead body are replaced by minerals (over time) from the material that surrounds it. This what a fossil actually is. You can date the fossil two ways:
Fossils can tell you a lot of information:
When a fossil is formed the hard parts of the dead body are replaced by minerals (over time) from the material that surrounds it. This what a fossil actually is. You can date the fossil two ways:
- By looking and analyzing the minerals that it is made from (as these are linked to specific times in history). The fossil will consist of particular sediment types from that period of time. Over time, sediment changes, so the fossil may end up elsewhere but the sediment within the fossil can be used to see when the fossil was formed.
- By looking at where the fossil is found and the sediment it is in - how many layers deep it is found, etc. Older fossils are found deeper in the ground than newer fossils.
Fossils can tell you a lot of information:
- Which hominins were anatomically similar/different (and perhaps more closely/distantly related)
- How big brains were (by looking within the skull)
- What the diet of the hominin was (looking at jaw, teeth, zygomatic arch)
- What they were killed by (sometimes)
- If there was any form of spirituality among the group (the way the hominin was buried)
- Where hominin lived (site hominin was found)
- When hominin lived (dated back to a specific time)
There are two types of DNA that scientists look at to discover more about human evolution: DNA from the nucleus and mitochondrial DNA (mtDNA).
Regular DNA can be used to look for
Regular DNA can be used to look for
- The presence of particular genes - genes in common suggests a closer genetic relationship than those with genes not in common.
- Similarities in the DNA sequence of particular sections of DNA - the more similar the genetic code, the more closely related the individuals.
Mitochondria have their own set of DNA and this gets passed down the maternal line only. It is useful because:
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