Write down some ideas you have about what Natural Selection is. Bell Time Activity Write down some ideas you have about what Natural Selection is.

Natural Selection Learning objective: To know what Natural Selection is. Success Criteria: (Even better): Use knowledge of Natural Selection to explain why some animals are extinct. (Great): Explain why some organisms survive better than others due using knowledge of Natural Selection (Good): Describe why some organisms survive better than others

STARTER -Take off touch down Stand up=take off if you know it /have done it Sit down=touch down if you don’t know/ haven’t done it yet Have had a new teacher at least once this year Know what an inherited characteristic is Have your birthday before December 31st Have a pet Can give at least two examples of an environmental variation Can draw a punnett square for a given characteristic

What is Natural Selection? Charles Darwin proposed the theory of Natural Selection by looking at finches (a type of bird).

What is Natural Selection? Darwin noticed that finches had adapted beaks to suit what food they had in that habitat.

What is Natural Selection? Teacher notes This five-stage sequence examines natural selection among a population of different coloured rabbits. Suitable prompts could include: These rabbits look different. Could natural selection happen if every member of the rabbit population was identical? What's the key thing the rabbits have to be able to do to make sure their genes are passed on to the next generation? What might prevent a rabbit living long enough to reproduce? Which of these rabbits looks best adapted to their icy environment? How is the number of white and brown rabbits likely to change in the future?

Survival of the Fittest? Reproduction is a very wasteful process. Animals and plants always produce way more offspring than the environment can support.

Survival of the Fittest? Individual species show lots of variation because of the different genes they inherit Only the offspring with the genes best suited to their habitat will stay alive and breed successfully. Many animals produce lots and lots of offspring to ensure that at least some will survive and pass on their genes.

Why do you think Sir David believes this?

Humans – still evolving? Natural selection means the organisms without specific characteristics die first (hence survival of the fittest) We have means to stop our ‘weakest’ organisms from dying off: Medicine Protection/Shelter Technology Most animals don’t have this!!

What about mutation? New forms of genes result from changes in existing genes. These changes are mutations. Mutations happen due to mistakes made when copying DNA when cells divide. They introduce more variety into the genes of a species. Why is this important for evolution?

What about mutation? If the mutation that occurs results in a characteristic that helps the animal compete and survive then it will be passed on to the next generation. Over time this mutation may become a common gene in the population.

True or false? Teacher notes This true-or-false activity could be used as a plenary or revision exercise on natural selection, or at the start of the lesson to gauge students’ existing knowledge of the subject matter. Coloured traffic light cards (red = false, yellow = don’t know, green = true) could be used to make this a whole-class exercise.

Extinction Extinction is the permanent loss of all the members of a species from the face of the Earth In pairs: What might cause an animal to become extinct?

Extinction Environmental changes (Dinosaurs) E.g. If animals suited to hot weather enter an ice age More competition (Birds species on Guam) If a mutation happens in one species that helps it survive really well or a new species moves into the area A new disease (Tasmanian devil) E.g. If a population of animals gets a disease which none of them are resistant to. This is especially bad if the whole population live close together (e.g. on an island)

Task For either natural selection OR extinction:- Produce a cartoon strip showing the steps of the process

Plenary Exam Practice!! INDIVIDUAL WORK 8 marks total Write the letter – don’t write the question out!! 10 minutes total

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Plenary Exam Practice!! Swap your book with the person sitting next to you. Mark it in red pen Give them a mark out of 8, sign your name underneath and hand books back

rag123 LO: To know what Natural Selection is. POLITE REMINDER: HOMEWORK DUE TUESDAY 9TH rag123 LO: To know what Natural Selection is. (Even better): Use knowledge of Natural Selection to explain why some animals are extinct. (Great): Explain why some organisms survive better than others due using knowledge of Natural Selection (Good): Describe why some organisms survive better than others Behaviour: R = poor behaviour A = okay G = outstanding! Understanding: 1 = I get everything! 2 = I understood most of it 3 = I need more help! Write a comment about what you liked/didn’t like/were good at/struggled with etc etc