Natural Selection and Mutations : Not Just for superheroes 3.1

What is a mutation?

• A change in an organism’s diet

• A random change in a gene that sometimes results in a new trait

• A type of environmental factor

• A predictable pattern of inheritance

What evidence suggests that poison levels in rough-skinned newts changed over time?

• Scientists observed that newts were growing larger over time

• Histograms showed changes in poison levels across generations

• All newts suddenly became poisonous in one generation

• Predators stopped eating newts because they changed colors

How do mutations contribute to natural selection?

• Mutations always harm an organism

• Mutations create new traits that may help an organism survive in its environment

• Mutations prevent populations from evolving

• Mutations only happen when an organism wants to change

What does a histogram of a population help scientists understand?

• The lifespan of individual organisms

• The distribution of traits within a population over time

• How many times an organism mutates in a year

• The total number of genes in a species

Why did the poison level trait become more common in rough-skinned newts?

• Newts that had higher poison levels were more likely to survive and reproduce

• The poison made newts stronger and faster

• The environment created poison inside the newts

• Newts decided to become more poisonous over time

Which statement is true about mutations?

• All mutations are harmful

• Mutations happen randomly and can be beneficial, neutral, or harmful

• Mutations always improve an organism’s survival

• Mutations only happen in laboratory settings

What role does the environment play in natural selection?

• The environment selects which traits are useful for survival

• The environment causes organisms to mutate

• The environment decides which genes an organism will inherit

• The environment has no effect on traits in a population

Why might some ostrilopes survive better than others in a cold environment?

• They learn to generate heat through behavior

• They inherit traits that help them stay warm, like thicker fur

• They mutate instantly to adapt to the cold

• They develop new traits only after many generations

What happens when mutations lead to adaptive traits in a population?

• The traits disappear quickly

• The population remains the same

• The traits become more common over time if they help survival

• The mutations stop occurring

How did the rough-skinned newt’s poison levels change over time?

• Poison levels increased due to mutations and natural selection

• Newts learned how to produce poison as they got older

• The poison was artificially added by scientists

• The poison appeared suddenly in every newt at the same time