A scientist observes that some fish in a lake have larger fins than others. When the water current becomes stronger, which group of fish is more likely to survive?

If a disease affects only plants with thin leaves, what will likely happen to a population of plants with both thin and thick leaves?

A population of insects includes individuals with long legs and short legs. If the environment becomes flooded, which variation is likely to be a disadvantage?

A group of birds has different beak shapes. If the main food source changes from seeds to insects, which birds are more likely to survive?

A population of lizards lives in a desert where the temperature is rising. Some lizards can tolerate higher temperatures. What is the likely outcome for the population?

A certain type of flower can be red or yellow. If pollinators prefer red flowers, what will likely happen to the population over time?

A population of mice has some individuals with longer tails and some with shorter tails. If predators can easily catch mice with longer tails, what is the likely effect on the population?

A group of plants can survive with little water, while others need a lot of water. If a drought occurs, which plants are at an advantage?

A population of beetles includes both green and brown individuals. If the environment becomes mostly brown, which beetle color is likely to be a disadvantage?

A population of birds lives in an area where the climate is becoming colder. Some birds have thicker feathers than others. Predict which birds are more likely to survive and explain why.

Suppose a population of frogs has some individuals that can jump farther than others. If a new predator is introduced that can only catch frogs that jump short distances, what will likely happen to the population over several generations? Explain your reasoning.

A population of trees has some individuals with deep roots and others with shallow roots. If the area experiences a long drought, which trees are more likely to survive and why?

Imagine a population of moths where some are light-colored and some are dark-colored. If pollution darkens the trees in their environment, which color moth is likely to have a survival advantage? Explain your answer.

A population of fish includes some that can tolerate polluted water and some that cannot. If the water becomes polluted, what will likely happen to the population over time? Use evidence to support your answer.

A population of deer has some individuals with larger antlers and some with smaller antlers. If larger antlers help defend against predators, what is the likely effect on the population? Explain your reasoning.

A population of bacteria includes some that are resistant to antibiotics and some that are not. If antibiotics are introduced, which group will have a survival advantage and why?

A population of squirrels includes some that can store more food than others. If a harsh winter occurs, which squirrels are more likely to survive and why?

A population of plants has some individuals that can grow in shade and others that need full sunlight. If a forest fire reduces the amount of shade, which plants are at a disadvantage and why?

A population of insects includes some that are resistant to a certain pesticide and some that are not. If the pesticide is used regularly, what will likely happen to the population over time? Explain your answer.

A population of wolves has some individuals with thicker fur and some with thinner fur. If the climate becomes much colder, which wolves are more likely to survive?

A population of turtles includes some that can swim faster than others. If a new predator is introduced that catches slow turtles, which turtles are at a disadvantage?

A population of grasshoppers includes some that are green and some that are brown. If the grass in their environment dies and the ground turns brown, which color grasshopper is more likely to survive?

A population of crabs includes some with hard shells and some with soft shells. If predators that can easily break soft shells become more common, which crabs are at a disadvantage?

A population of plants includes some that can survive in salty soil and some that cannot. If the soil becomes saltier, which plants are more likely to survive?

A population of birds includes some that migrate and some that do not. If winters become much colder, which birds are at an advantage?

A population of frogs includes some that can survive in polluted water and some that cannot. If the water becomes polluted, which frogs are at a disadvantage?

A population of foxes includes some with better hearing than others. If prey becomes harder to find, which foxes are more likely to survive and why?

A population of ants includes some that can survive in very hot temperatures and some that cannot. If the climate becomes much hotter, what will likely happen to the population over time? Explain your answer.

A population of butterflies includes some that can fly long distances and some that cannot. If their food source moves farther away, which butterflies are more likely to survive and why?