Fossil Evidence for Human Evolution Flashcards
What fossils have provided evidence for human evolution?
- Ardi
- Lucy
- Turkana Boy
How old is the hominid fossil ‘Ardi’?
4.4 million years old
How old is the hominid fossil ‘Lucy’?
3.2 million years old
How old is the hominid fossil ‘Turkana Boy’?
1.6 million years old
Which scientist discovered the hominid fossil ‘Turkana Boy’?
Richard Leakey
Which characteristics of the hominid fossil ‘Ardi’ have given scientists clues about human evolution?
She shows phenotypic traits which encompass characteristics of both humans and apes:
- Ape-like characteristics e.g. long arms, large big toes
- Human-like characteristics e.g. the structure of her bones suggests that she walked upright
(belonged to species Ardipithecus ramidus)
Which characteristics of the hominid fossil ‘Lucy’ have given scientists clues about human evolution?
She shows phenotypic traits which are more human-like than that of ‘Ardi’:
- The structure of bones in her legs and feet are more adapted to walking than climbing
- However, her brain size is closer to that of an ape’s
(belonged to species Australopithecus afarensis)
Which characteristics of the hominid fossil ‘Turkana Boy’ have given scientists clues about human evolution?
‘Turkana Boy’ showed traits comparable to that of modern-day humans:
- Had short arms and long legs which were much more like a human than an ape
- Its brain size was much larger than Lucy’s - similar to human brain size
(belonged to species Homo erectus)
The ‘homo habilis’ species existed 1.5 - 2.5 million years ago.
Describe the type of tools this species used.
- Made simple stone tools called pebble tools by hitting rocks together to make sharp flakes
- These could be used to scrape meat from bones or crack bones open
The ‘homo erectus’ species existed 0.3 - 2 million years ago.
Describe the type of tools this species used.
- Sculpted rocks into shapes to produce more complex tools like simple hand-axes
- These could be used to hunt, dig, chop and scrape meat from bones
The ‘homo neanderthalensis’ species existed 25,000 - 300,000 years ago.
Describe the type of tools this species used.
- More complex tools
- Evidence of flint tools, pointed tools and wooden spears
The ‘homo sapiens’ species has existed from 200,000 years ago to present day.
Describe the type of tools this species used.
- Flint tools widely used
- Pointed tools including arrowheads, fish hooks and needles appeared around 50,000 years ago
(Exam-style question)
Explain how stone tools provide evidence for the evolution of the brain in human ancestors.
- Stone tools became more complex in shape over time
- This suggests that the brain was getting larger as it allowed human ancestors to create more complex tools
Stratigraphy is the study of rock layers.
Describe how stratigraphy allows scientists to determine how old tools and fossils are.
Older rock layers are normally found below younger layers, so tools or fossils in deeper layers are usually older
Apart from stratigraphy, give two methods that a scientist could use to date stone tools at a fossil site.
- Studying the structural features of the tools
- Using carbon-14 dating to date any carbon-containing material found alongside the tools
