1. In pairs – write down a definition for the word.
What is the anagram? (don’t shout it out)
tidyribsevio
Biodiversity
In pairs – write down a definition for the word.

2. Learning outcomes All of you should be able to:
Define the terms biodiversity, genetic diversity, species diversity and habitat diversity.
Define species and speciation
Most of you should be able to:
Outline the mechanism of natural selection.

3. What is biodiversity?
Biodiversity = Biological diversity “The variety of life on earth” Up until now when talking about biodiversity we have focussed on species diversity but there are two other aspects…

4. Biodiversity includes three aspects
Genetic diversity
Species diversity
Habitat diversity
What do you think these three different aspects of biodiversity mean?
Individually: write down what you think each one means.
HINT: you should already know species diversity.
Now have a look at what you have written and compare it with the following definitions.
Is there anything that you are missing?
Add it to your definition.

5. Species diversity Genetic diversity Habitat diversity
The variety of species within a given area, habitat or region. This includes the number of species and the number of individuals of each species
This variety alters from habitat to habitat. The rainforests at one end with great variation and the polar ice caps at the other with little variation.
The range of genetic material present in a gene pool or population of a species.
Wild mustard species have much more genetic diversity than the domestic varieties
Habitat diversity
The number of different habitats per unit area that a particular ecosystem or biome contains. If diversity increase here it will probably lead to an increase in the other two.

6. Speciation
Speciation is the process by which new species form.

7. Hysterocrates maximus
What is a species?
Equus africanus
Hysterocrates gigas
Ursus maritimus
Equus ferus
Ursus arctos
Hysterocrates maximus

8. A species is defined as:
A group of organisms that can interbreed and produce fertile offspring.

9. + =
Mules cannot reproduce themselves so although donkeys and horses can mate they are considered different species.

10. How does speciation occur?

11. Darwin’s discovery
Charles Darwin published On the Origin of Species
Culmination of his life’s work
Outlined theory of the evolution of species by natural selection
Species change over time due to natural selection, creating new and different species

12. Darwin knew about artificial selection, and argued that a similar process must occur in nature.
Wild mustard
& domestic
cruciform vegetables
Domestic dogs
Wild canids

13. Artificial Selection
nature provides variation, humans select variations that are useful.
Example - a farmer breeds only his best livestock

14. This led him to the idea of natural selection.

15. Get down Darwin’s four key points…

16. Natural selection
Also called “survival of the fittest” What do you understand by the term fitness in this context? Let’s have a go at the worksheet…

17. Natural Selection and Species Fitness
Overtime, natural selection results in changes in the inherited characteristics of a population.
These changes increase a species fitness (survival rate)

18. What adaptations do these animals show that increase their fitness for their environment?

20. Let’s finish there Put your notes away: Define biodiversity
Define species diversity, genetic diversity and habitat diversity
Define speciation
Outline the mechanism of natural selection

21. Now take your partner’s and check it… add anything that they have missed.
Biodiversity
The variety of life on earth – can include habitat diversity, species diversity and genetic diversity
Species diversity
Variety of species per unit area – number of species and relative abundance (number of individuals of each species)
Habitat diversity
The range of different habitats in an ecosystem
Genetic diversity
The range of genetic material present in a gene pool or species population
Speciation
This is the process by which new species are formed
Outline the mechanism of natural selection
Each organism will be adapted slightly differently to their environment. Resources are limited and there will be competition for resources. These small differences mean that some organisms will be more successful than others and more likely to survive and reproduce, passing their genes on to the next generation. Survival of the fittest.