SB4a – Evidence for human evolution
Starter: Write down what you think
‘evolution’ means
Extension: How can we be sure that
evolution had happened?
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Learning objectives:
- Define ‘evolution’.
- Recognise binomial species names.
Explain how evidence from fossils and stone
tools supports current ideas about human
evolution.
Recall how stone tools are dated from their
environment.
- Describe how stone tools created by
human-like species have developed over
time.
Tuesday, 18 January 2022
Evolution is the slow and continuous change
of organisms from one generation to the
next.
We can see evidence for evolution in fossils.
Fossils give us an idea of the structure and
adaptations of organisms.
Evolution
Evolution – the gradual change in characteristics
of a species over time.
Scientists used fossils to find out about human
evolution.
Fossils are preserved remains of any once-living
organism from a past geological age.
Fossils records provide evidence for evolution.
Binomial system and Darwin
To name species, a binomial system is
used. This uses two Latin words.
What is the binomial name for humans?
Homo sapiens
Charles Darwin was an English scientist
who studied variation in plants, animals
and fossils. He proposed the theory of
evolution by natural selection.
Darwin’s theory
The theory of natural selection proposed:
- Individual organisms within a particular species
show a wide range of variation.
- individuals with characteristics most suited to the
environment are more likely to survive and to
breed successfully.
- the characteristics that have enabled these
individuals to survive are then passed on to the
next generation.
Darwin’s ideas was not accepted at the time as it
conflicted with Christian religious beliefs.
Wallace’s theory
Alfred Wallace – proposed the theory of
speciation, and therefore evolution by natural
selection.
Speciation – occurs when a group within a species
separates from other members of its species and
develops its own characteristics.
Wallace proposed variation within a population as a
results of genetic mutations.
Alleles provide a survival advantage. Isolation of
species could be due to physical barriers.
New species can be formed due to these factors
Questions
Compare the main differences between Darwin’s and
Wallace’s theory. (4)
Explain why Darwin’s work was
disapproved? (2)
Darwin’s theory proposed the theory of evolution
as natural selection. (1)
The theory of evolution conflicted
with Christian religious beliefs.
(1)
individuals with characteristics most suited to the
environment are more likely to survive and to
breed successfully. (1)
Science was not advanced back
in the 17th century. (1)
Wallace’s theory proposed the theory of
speciation. (1)
Lacked evidence as it was just a
theory. (1)
Wallace proposed variation within a population as
a results of genetic mutations. (1)
Exam Questions
Fossils - Ardi
Fossils are preserved remains of any once-living
organism from a past geological age.
Scientists can use fossils to find out about human
evolution.
Scientists can work out how old fossils are and can
put them in age order.
In 1992, scientists discovered a 4.4
million year old fossilised bones.
They believed the fossil was from a
female of an extinct human-like
species.
These fossils were nickname Ardi.
https://www.youtube.com/watch?v=K79cNuZFwhM
Stone Tools
https://www.youtube.com/watch?v=DEULGf-tyIU
Questions
Stone Tools
https://www.youtube.com/watch?v=DEULGf-tyIU