Download File

Weekly Plan 27
Evolution
Student book links
Specification links
Link to GCSE specification
Suggested time allowed:





 2.3.3 (a)–(j)




Nine hours
2.3.10
2.3.11
2.3.12
2.3.13
2.3.14
Variation
Adaptation
Evolution
Inheritance
Weekly learning outcomes
Students should be able to:
 Define the term variation.
 Discuss the fact that variation occurs within as well as between species.
 Describe the differences between continuous and discontinuous variation, using examples of a range of
characteristics found in plants, animals and microorganisms.
 Explain both genetic and environmental causes of variation.
 Outline the behavioural, physiological and anatomical (structural) adaptations of organisms to their
environments.
 Explain the consequences of the four observations made by Darwin in proposing his theory of natural
selection.
 Define the term speciation.
 Discuss the evidence supporting the theory of evolution with reference to fossil, DNA and molecular
evidence.
 Outline how variation, adaptation and selection are major components of evolution.
 Discuss why the evolution of pesticide resistance in insects and drug resistance in microorganisms has
implications for humans.
Lesson time allocated:
Suggested teaching order
1. Examine variation using a range of subjects
2. Distinguish continuous/discontinuous and
genetic/environmental
3. Look at animal and plant adaptations and how they can
enhance survival and reproduction within their habitat
4. Examine Darwin’s observations and deductions.
5. Variation, adaptation and selection as major
components of evolution by natural selection
6. Evidence supporting evolution by natural selection.
7. Speciation
8. Evolution in action – resistance of microbes and insects
Key words
How science works
Variation. Continuous variation. Discontinuous variation. DNA. RNA. Allele. Gene. Species. Hypha.
Adaptation. Xerophyte. Evolution. Photosynthesis. Disease. Enzyme. Respiration. Stomata. Water
vapour potential. Diffusion. Transpiration. Pits. Speciation. Natural selection. Selection pressure.
Allopatric. Sympatric. Protein. Amino acid. Diversity. Metabolism. Receptor site. Antibiotic.
 HSW 2: Use knowledge to present arguments
 HSW 3: Use appropriate methodology to examine
variation and natural selection
 HSW 5: Investigative work
 HSW 7: Reactions to Darwin’s ideas
© Pearson Education Ltd 2008
This document may have been altered from the original
1
Weekly Plan 27
Learning styles (S = Starter activities, M = Main activities, P = Plenary activities)
Kinaesthetic
Activity S2
Activity M1–M3
Activity P1
Interpersonal
Activity S1–S3
Activity M1–M3
Activity P1&P2
Auditory
Activity S1&S3
Activity M1–M3
Activity P1–P3
ICT activities
Visual
Activity S1–S3
Activity M1–M3
Activity P1&P3
 Internet in S1–S3, M2–3, P3, Homework suggestions and
Extension ideas sections Excel in M1
 Tutorial: An origin of species
 Activity: Camouflage and predation (Peppered Moth)
 Website: Natural History Museum
Suggested starter activities
Equipment
Teacher notes
1. Watch Planet Earth videos or give students living
examples of animals with interesting adaptations.
Internet access, computer, projector
Video: Planet Earth clips.
In groups, students have to identify as many adaptations as
possible.
2. As a class, play The Peppered Moth game or the
Natural History Museum beetle game on an interactive
whiteboard.
Internet access, computer, projector
Activity: The evolution game
3. Watch ‘Right here, right now’ video from Fat Boy Slim.
Internet access, computer, projector
You can search for the video on YouTube. Discuss the
extent to which the video really models the process of
evolution.
Suggested main activities
Equipment
Teacher notes
1. Using brine shrimps, snails, leaves, or flowers as
examples, students have to collect data for as many
different variables as possible – give no guidance on
which variables or how to graph them until plenary
discussion.
Website: British Ecological Society - details of
the Brine Shrimp Ecology book and materials,
including free downloads
Analyse data using ICT. Help students to identify
continuous/ discontinuous and genetic/environmental
variation.
2. Model effects of natural selection mathematically or
investigate natural selection by providing birds with a
choice of differently-coloured pieces of spaghetti.
Differently-coloured pieces of spaghetti,
binoculars, Internet access, computer,
projector
Students lay out bait and observe predation rates in relation
to colour to mimic natural selection. A variety of models of
natural selection are available – use the Internet to search
using terms natural selection and model.
3. Use the resources listed in the ICT activities section to
plan a classroom debate and write character briefs on the
contribution made by the different personalities to the
acceptance of evolution by natural selection.
Internet access, computer, projector
Notes: Development of evolutionary theory
© Pearson Education Ltd 2008
This document may have been altered from the original
2
Weekly Plan 27
Suggested plenary activities
Equipment
Teacher notes
1. Put examples of variation on stickers for students to
wear.
Stickers with examples of variation drawn on
Ask them to rearrange themselves according to
genetic/environmental or continuous/discontinuous.
Internet access, computer, projector
Video: Ken Bingham on evolution
2. Play What’s on the tip of my tongue. For example, read
out Darwin’s observations – students respond with
deductions.
3. Watch the Ken Bingham video and identify his students’
misconceptions about evolution.
Homework suggestions
 In groups, produce a storyboard flowchart for an animation of the process of evolution by natural selection and resultant speciation.
 Research the adaptations of xerophytic and halophytic plants and the development of resistance in populations of bacteria and insects.
 Use the Internet to research reports about tuskless elephants being born due to selection pressures exerted by poachers in Africa.
Cross-curriculum links
 General studies – conservation
 Religious education (Philosophy and ethics) – you can help students to understand that the debate between natural selection and creationism is not really a concern of
science, as there is no evidence for creationism and science is not about faith.
Extension ideas
 Research sexual reproduction as an evolutionary strategy, as opposed to asexual reproduction. Essay: The advantage of sex.
 Research and explain the Hardy–Weinberg equation and its implications for population dynamics.
 Research the evidence for evolution before writing an analysis of it.
Potential misconceptions
 Students commonly have difficulty with distinguishing between allopatric and sympatric speciation.
 Students continue to hold ideas of design – particularly after discussing variation and adaptation – even if they hold no religious beliefs. Students with religious beliefs
may find it hard to reconcile them with natural selection.
 Many students continue to believe in acquired characteristics – e.g. giraffes’ necks get longer because they stretch for food and their children then have long necks.
 Some students assume that unused features will disappear over evolutionary time without realising a selection pressure would be required to make that happen.
Notes
The web links referred to here are some that the author has found personally helpful but are not intended to be a comprehensive list, many other
good resources exist.
© Pearson Education Ltd 2008
This document may have been altered from the original
3