5.4: the theory of evolution

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 2

Endtest toetsweek

Evolution 

After today

You can describe the theory of evolution by using the key concepts.

Key concepts:

Evolution – variation – natural selection – changes of survival – isolation.

Evolution has to do with ..

Evolution is about...

• The emergence of new species (all organisms)
• The way in which these species arise
• Determining which species are related to each other

Evolution is NOT about ..

• How life came to be
• How the universe/solar system/earth/etc. came to be
• If God exist

3 main mechanisms

Evolution can be summarized  into these 3 mechanisms:

1. Variation in genotypes
2. Natural selection
3. New species arise

What are the causes of genetic variation?

Variation in genotypes

• Sexual reproduction > new/different genotypes
• New genotypes > new phenotypes
• Mutations also create new variation

Natural selection

• Species who have adapted to 

        their environment will survive

        and reproduce

• 'Good' genes are  passed  on
• 'Bad' genes dissapear

New species arise

Animals of same species are  split up

The environment slowly changes.

Because of natural selection, other genes are 'good' in new environment

Species have become different species after many years of evolution, due to living apart

more examples

New species arise

• New species arise due to LONG periods of evolution in a species
• Many small changes together  become big changes

• Evolution takes very long! (thousands of years)

Summarizing

Genetic variation created by mutation and recombination  variation

Variation is passed on  heredity

Environment select survivors

Survival of the fittest

What is the deciding 'thing' that tells you that two organisms belong to the same species?

Different species?

Start working

Homework

Theme 5 Heredity and evolution

Basic 4

1,2, 3, 5, 7 and 8

Agenda

• Homework check
• Short recap basic 4 
• Instruction basic 5
• Homework
• Finishing Freek Vonk college 

Remember?

Describe what is happening here. 

Use the words: variation, natural selection,  survival of the fittest.

Adaptation

the adjustment of organisms to their environment in order to improve their chances at survival in that environment.

Put in the right order of natural selection

Adaptation

Selection

Variation

Summarizing

Genetic variation created by mutation and recombination  variation

Variation is passed on  heredity

Environment select survivors

Survival of the fittest

Question 7 of basic 5.4

How does the resistance against antibiotic of the bacteria develop?
Write it down in 3 steps.

Basic 5 the history of life on earth 

After today you..

can explain how fossils arise 

Can explain that species are related to a common ancestor

Geological timescale

Divided into time periods

Each with distinctive climate

What is the evidence behind?

By fossils

Requirements of fossils

• Time
• Sediment 
• No oxygen

Common ancestor

Kinship of species

• The amount you are related to a common ancestor

Is the following statement true or false?

Cebochoerus is the ancestor of the whole pig family.

Similarity in structures

• organs can have the same structure but very different functions
• Most probably come from (derived) from the same original structure
• These animals therefore probably have a common ancestor

Rudimentary organs

Homework 

Theme 5

Basic 5 

Question: 2,5,6,7 

5 causes of evolution

• Small population: shrinkage of alleles frequencies
• Non random matig: sexual preferences
• Mutations: lead to new genotypes and phenotypes
• gene flow: migration of genes 
• Natural selection: environment filters genes

What you should do:

• Read lesson material 5.4
• Do asgmt 1-3, 5,6,7
• Challenge yourself: 8, 9

Done with the above?

• Learn for the test 
• Make other homework
• Read a book

Working with whispering

• Teacher is available for questions
• Only whisper with the student next to you
• Stay at your  desk