Essential Idea
The diversity of life has evolved and continues to evolve by natural selection.
Understandings
Natural selection can only occur if there is variation among members of the same species.
Mutation, meiosis and sexual reproduction cause variation between individuals in a species.
Adaptations are characteristics that make an individual suited to its environment and way of life.
Species tend to produce more offspring than the environment can support.
Individuals that are better adapted tend to survive and produce more offspring while the less well adapted tend to die or produce fewer offspring.
Individuals that reproduce pass on characteristics to their offspring.
Natural selection increases the frequency of characteristics that make individuals better adapted and decreases the frequency of other characteristics leading to changes within the species.
Applications
Changes in beaks of finches on Daphne Major.
Evolution of antibiotic resistance in bacteria.
Skills
None
Guidance
Students should be clear that characteristics acquired during the lifetime of an individual are NOT heritable. The term Lamarckism is NOT required.
Key Vocabulary
Here
Textbook Reading and/or Activities
Click HERE for a pdf of chapter 5.
Pages 241-252
Challenge Yourself (p.245)
Nature of Science (p.251)
TOK (p.251)
Exercises (p.252)
Notes and Study Questions
Bob Smullen Notes Study Questions
Jacob Cedarbaum Notes Study Questions
Stephen Taylor Notes (Slides 1-38) Study Questions
Chris Paine Notes Study Questions
Learning Activities
This article, published by The Atlantic (Sept.8, 2016), describes the real-time evolution of bacteria in an experiment conducted at Harvard University. It includes an awesome 2 minute video.
This 16 minute video (with challenge questions), produced by hhmi BioInteractive, explores Darwin's examination of the finches he collected while devising natural selection as the mechanism for evolution.
This activity, prepared by an unknown source, outlines the scenario that occurred during industrialization in London whereby excessive soot released from factories led to a change in the colour of trees and consequently, the moths that lived on those trees.
This activity examines the varying rates of success that different characteristics can lead to for an individual. Data.
Making of the Fittest: Natural Selection and Adaptation
This 10 minute video (with challenge questions), produced by hhmi BioInteractive, examines the changes that a population of pocket mice have undergone in response to changes in their environment.
Supplemental Reading
Title
Description
This video examines the unfortunate reality that some bacteria are evolving resistance to the antibiotic drugs that we use to keep ourselves healthy.
Should Watch Videos
This video examines the various aspects of natural selection and how these result in changes within a population.
This video examines the process by which natural variation between the individuals of a species results in certain individuals being more likely to survive and reproduce.
This video examines the manner in which variation comes to be within a species and how this variation can lead to changes in a population.
Must Watch Videos
This video examines the process by which bacteria are becoming resistant to antibiotics.