Year 10 Science · Unit 1 · Lesson 12
Foundation Worksheet
Learning Goals
Order the steps
Number Darwin's five postulates from 1 to 5 to show their correct logical order. Step 1 = what must be true first.
| Order | Postulate |
|---|---|
| Heritability: Advantageous traits are passed from parents to offspring through genes. | |
| Differential survival: Individuals with traits better suited to the environment survive and reproduce more successfully than others. | |
| Overproduction: More offspring are produced than can possibly survive to adulthood, there is a surplus of young. | |
| Variation: Individuals within a population differ in their traits, no two individuals are identical. | |
| Competition: Organisms struggle for limited resources (food, water, mates, territory), not all can survive. |
True or False? Fix the false ones
Circle T or F for each statement. If the statement is false, rewrite it correctly on the line below.
Bacteria evolve antibiotic resistance in order to survive, they sense the antibiotic and produce the resistance mutation in response.
Correct it:
Natural selection acts on populations over many generations, not on individual organisms during their lifetime.
Correct it:
If you get very fit through exercise, your children will automatically inherit your increased fitness level.
Correct it:
Fitness in biology means reproductive success, the ability to produce surviving offspring, not physical strength or speed.
Correct it:
1. Australian hospitals reported over 11,000 cases of multi-drug-resistant bacteria in one year. Using Darwin's postulates, explain in 3–4 sentences how antibiotic resistance develops in a bacterial population when patients take antibiotics.
2. The thorny devil is an Australian lizard with sharp spines that deter predators. Explain, using the concept of differential survival, how the thorny devil's spines could have become more pronounced over many generations.
Wrap Up
In one sentence, explain what natural selection selects on and what it selects for.