Evolution 1
Who is credited with discovering the theory of evolution?
Charles Darwin
Define abiotic factor
A non-living factor of the environment
Name a vestigial structure in humans
tailbone, appendix, wisdom teeth
Peppered moth population becoming darker is an example of what type of selection?
Directional
Define biotic factor
A living component of the environment
What are human arms and whale flippers an example of?
Homologous structures
Define population
whole number of people or inhabitants in a country or region.
Define selection pressure
any external or internal factor that makes it harder or easier for organisms with specific traits to survive and reproduce
What are bat wings and butterfly wings an example of?
Analogous features
Define species
a group of similar living organisms that can breed together and produce fertile offspring.
What was the common name of the ancestral species of the modern horse?
The dawn horse
Analogous features are an example of what kind of evolution?
Convergent
What are the three methods of introducing variation to a population?
Mutation, Meiosis, Fertilisation
1. Variation
2. Selection pressure
3. Survival of the fittest
4. Heredity
Homologous features are an example of what kind of evolution?
Divergent
Why does greater genetic variation increase the likelihood that a population will survive environmental change?
Genetic variation means individuals have different characteristics. If the environment changes, some individuals may have characteristics that give them an advantage, allowing them to survive and reproduce and pass those alleles to future generations.
Fossil record
Biogeography
Similar features
DNA evidence
Why don't individual members of a population evolve?
Evolution is a change in the frequency of a specific trait in a population over multiple generations.
What type of environment causes disruptive selection?
A very large environment or the spread of a species across a large environment
What type of environment favours directional selection?
an environment undergoing change
What does the appendix prove about human ancestry?
That we used to be herbivores and needed the appendix to house bacteria to break down plant matter
Explain how comparative anatomy is a piece of evidence for proving the theory of natural selection
Comparative anatomy supports evolution by showing how different species share similar body structures inherited from a common ancestor.
Using the 4 steps of natural selection, explain how penguins have developed a thick layer of feathers over time.
1. There were some penguins with thicker feathers than others
2. Selection pressure was the cold climate
3. The thicker feathered penguins were more suited to the environment and survived the cold
4. These penguins passed on their genes, making thick feathers more prevalent in the population
This happens when a group within a species separates, stops interbreeding with the rest of the group, and accumulates enough genetic differences to become a completely separate species
Explain how fossil evidence can be used to support the theory of evolution
The fossils provide evidence that organisms have changed over time and can show transitional characteristics between earlier and later forms.