Natural Selection
What is natural selection?
The process where individuals with advantageous traits are more likely to survive and reproduce.
What is artificial selection?
The selective breeding of organisms by humans to produce desired traits.
What is a mutation?
A change in an organism's DNA sequence.
What is speciation?
The formation of new species.
Which country won the 2026 FIFA World Cup?
Spain
What must exist within a population before natural selection can occur?
Variation
Who controls which individuals reproduce during artificial selection?
Humans
What mechanism of evolution occurs when individuals move between populations and introduce new alleles?
Gene Flow
What must happen to populations before they can evolve into separate species?
They must become reproductively isolated.
What is Australia's largest state by area
Western Australia
A population of insects contains green and brown individuals. Birds can easily see the green insects. Which insects are more likely to survive?
brown insects
Broccoli, cauliflower, kale and cabbage all originated from the same wild plant. How could humans have produced such different plants from the same species?
Humans repeatedly selected plants with different desirable traits and bred them over many generations, resulting in different varieties through artificial selection.
What mechanism of evolution involves changes in allele frequencies due to random chance?
Genetic drift.
What is a species?
A group of organisms that can interbreed to produce fertile offspring.
What colour is an octopus's blood?
Blue
Explain why an individual organism does not evolve through natural selection.
Individuals are selected based on their traits, but populations evolve over generations as allele frequencies change
Give one difference between natural selection and artificial selection.
Natural selection is driven by environmental pressures, while artificial selection is driven by human choice.
A natural disaster randomly kills most members of a population. What type of genetic drift may occur?
Bottleneck effect
Explain how geographic isolation can eventually lead to speciation
Separated populations experience different selection pressures and accumulate genetic differences until they become reproductively isolated.
What is the chemical symbol for gold?
Au
A population of beetles contains both green and brown individuals. A mutation that causes brown colouring occurred randomly before a drought changed the environment. After the drought, the plants became brown, making brown beetles harder for predators to see. Over many generations, the proportion of brown beetles increased.
Explain how natural selection caused the population to change.
The random mutation produced variation in the population. The drought changed the environment, creating a selection pressure from predators. Brown beetles were better camouflaged, so they were more likely to survive and reproduce. Because the trait was heritable, it was passed to their offspring. Over many generations, the alleles associated with brown colouring became more common in the population.
Explain one potential disadvantage of artificial selection.
It can reduce genetic diversity, making populations more vulnerable to diseases or environmental changes.
Name the four main mechanisms of evolution.
Mutation, gene flow, genetic drift and natural selection.
A population of animals becomes separated into two different environments. In one environment, a random mutation causes some individuals to have thicker fur. The colder environment means individuals with thicker fur are more likely to survive and reproduce.
Explain how the random mutation and environmental pressure could eventually contribute to speciation.
The mutation occurs randomly and creates variation in fur thickness. The cold environment acts as a selection pressure, meaning individuals with thicker fur are more likely to survive and reproduce. Over many generations, the thick-fur trait may become more common. If the populations continue to accumulate differences and eventually become reproductively isolated, a new species may form.
Who holds the record for the most Olympic gold medals won by any individual in history?
michael phelps