AQA · GCSE · Biology
Course version: 8461 · Version from Sept 2018
The theory of evolution by natural selection is now widely accepted.
Full specification wording
Evidence for evolution: The theory of evolution by natural selection is now widely accepted.
The theory of evolution by natural selection explains how species change over time.
Checked against the AQA 8461 specification (opens in a new tab) on .
- Point 2 of 4
- 3 key terms
Study notes
From the checked teaching notes for this specification point.
The idea
The theory of evolution by natural selection explains how species change over time. Individuals in a population vary because of differences in their genes. Some variants are better suited to the environment, so they are more likely to survive and reproduce. Their offspring inherit the advantageous characteristics, so these become more common in the population over many generations. The theory is widely accepted because evidence from many areas of biology supports it, including the fossil record, the similarities between organisms, and observations of rapid evolution such as antibiotic resistance in bacteria. Acceptance means the scientific community treats it as the best explanation supported by evidence.
What earns the marks
- Variation exists within populations because individuals have different alleles, produced by mutation and sexual reproduction.
- Individuals with characteristics better suited to their environment are more likely to survive and reproduce, so they pass on the advantageous alleles.
- Over many generations, the proportion of individuals with advantageous characteristics increases, and the population changes.
- The theory is widely accepted because multiple independent lines of evidence, including fossils and antibiotic resistance, support it.
Common mistakes and how to put them right
Saying that individuals evolve.
Put it right: That populations evolve as allele frequencies change over generations.
Thinking that organisms choose to change to suit their environment.
Put it right: That variation arises randomly and natural selection acts on it.
Believing that acceptance means the theory is proven beyond all doubt.
Put it right: That it is strongly supported by a wide range of evidence.
Exam tips
- Use the phrase ‘survival of the fittest’ only if you also explain that ‘fittest’ means best suited to the environment, not strongest.
- Structure an explanation as variation, selection, inheritance and change over generations.
- Refer to named evidence, such as fossils or antibiotic resistance, to show why the theory is accepted.
Try the lesson
The start of the Evidence for evolution: The theory of evolution by natural selection is now widely accepted. lesson, made from checked teaching notes for this specification point.
Have a go first
Which statement best describes the current scientific consensus on the theory of evolution by natural selection?
Listen
The theory of evolution by natural selection explains how species change over time. Individuals in a population vary because of differences in their genes. Some variants are better suited to the environment, so they are more likely to survive and reproduce. Their offspring inherit the advantageous characteristics, so these become more common in the population over many generations. The theory is widely accepted because evidence from many areas of biology supports it, including the fossil record, the similarities between organisms, and observations of rapid evolution such as antibiotic resistance in bacteria. Acceptance means the scientific community treats it as the best explanation supported by evidence. A strong answer earns marks for these points. Variation exists within populations because individuals have different alleles, produced by mutation and sexual reproduction. Individuals with characteristics better suited to their environment are more likely to survive and reproduce, so they pass on the advantageous alleles. Over many generations, the proportion of individuals with advantageous characteristics increases, and the population changes. The theory is widely accepted because multiple independent lines of evidence, including fossils and antibiotic resistance, support it. A common slip: Saying that individuals evolve. Instead, that populations evolve as allele frequencies change over generations. Exam tip: Use the phrase ‘survival of the fittest’ only if you also explain that ‘fittest’ means best suited to the environment, not strongest.
See it
Key words
Say what each word means before you turn the card.
Natural selection
Try answering aloud or in your head before turning the card.
Variation
Try answering aloud or in your head before turning the card.
Scientific acceptance
Try answering aloud or in your head before turning the card.
See every definition
- Natural selection
- The process by which individuals with characteristics better suited to their environment are more likely to survive and reproduce, so advantageous characteristics become more common over many generations.
- Variation
- Differences between individuals in a population because of differences in their genes.
- Scientific acceptance
- The scientific community treats the theory as the best explanation supported by evidence.
Label the diagram
Some boxes have lost their names. Pick the right name for each number.
1Box 1
2Box 2
3Box 3
There is more to this lesson
The full lesson goes on to check your understanding and help you earn the marks. Create a free account to carry on, with your progress saved.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge
Test your understanding of Evidence for evolution: The theory of evolution by natural selection is now widely accepted.
Active recall beats re-reading. Take an instant quiz now to test what you’ve learned and lock it into long-term memory.
A week of Premium from your first lesson · Then the free plan continues · No card, no charge