Evolution & adaptation

Natural selection, fossils as evidence, variation, inheritance, and adaptation to environment

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1
Match each key term to its definition. Match each item on the left to one on the right. Left: Adaptation, Variation, Inheritance, Evolution Right: A feature that helps an organism survive in its environment, Differences between individuals of the same species, Characteristics passed from parents to offspring, Gradual change in a species over many generations
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2
What do fossils provide evidence of? A) How living things have changed over millions of years B) What the weather was like yesterday C) How fast animals can run today D) What food humans ate last year
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3
True or false? All characteristics are inherited from parents. The environment has no effect. A) True B) False
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4
A cactus has thick, waxy skin and spines instead of leaves. What is this an example of? A) Adaptation to a dry environment B) A reversible change C) Metamorphosis D) Camouflage for hiding from predators
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5
True or false? Natural selection means that the strongest individual always survives. A) True B) False
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6
Complete the sentence about natural selection. In natural selection, organisms with characteristics best suited to their environment are more likely to ___ and pass on their genes.
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7
Match each adaptation to the environment it helps the animal survive in. Match each item on the left to one on the right. Left: Thick blubber layer, Large ears for cooling, Webbed feet, Long, curved claws Right: Arctic (cold environment), Desert (hot environment), Wetland (aquatic environment), Rainforest (climbing trees)
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8
On an island, beetles come in green and brown varieties. Birds eat beetles they can see easily. The island has mostly green plants. Over many generations, what would likely happen? A) Green beetles would become more common because they are harder to see B) Brown beetles would become more common because they are stronger C) All beetles would turn green during their lifetime D) The beetles would not change at all
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9
Why is variation within a species important for survival? A) It means some individuals may survive if the environment changes B) It makes the species look more attractive C) It means all individuals are identical and equally strong D) It has no importance for survival
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10
True or false? Fossils show that many living things in the past were different from those alive today. A) True B) False
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Answer key

Evolution & adaptation · for parents and teachers

1
Adaptation → A feature that helps an organism survive in its environment; Variation → Differences between individuals of the same species; Inheritance → Characteristics passed from parents to offspring; Evolution → Gradual change in a species over many generations
These are the four key concepts in understanding how species change over time. Variation provides differences, some are inherited, adaptations help survival, and evolution is the long-term result.
2
How living things have changed over millions of years
Fossils show us what organisms looked like millions of years ago. By comparing fossils from different time periods, we can see how species have changed (evolved) over time.
3
False
Some characteristics are inherited (eye colour, natural hair colour) but many are affected by the environment (scars, muscle size, language spoken). Most features involve both.
4
Adaptation to a dry environment
Cacti are adapted to desert life. Thick waxy skin prevents water loss, and spines (modified leaves) reduce the surface area for evaporation while protecting from animals.
5
False
Natural selection favours organisms best adapted to their environment - this might mean being camouflaged, disease-resistant, or good at finding food. Strength is only one possible advantage.
6
survive
Natural selection works because better-adapted organisms are more likely to survive, reproduce, and pass their helpful characteristics to their offspring over many generations.
7
Thick blubber layer → Arctic (cold environment); Large ears for cooling → Desert (hot environment); Webbed feet → Wetland (aquatic environment); Long, curved claws → Rainforest (climbing trees)
Each adaptation solves a specific survival problem: blubber insulates against cold, large ears radiate heat away, webbed feet aid swimming, and curved claws help grip tree bark.
8
Green beetles would become more common because they are harder to see
Green beetles are camouflaged against green plants, so birds eat fewer of them. More green beetles survive to reproduce, passing on the green colour gene. Over generations, green becomes more common.
9
It means some individuals may survive if the environment changes
Variation is like an insurance policy. If the environment changes (new disease, new predator, climate change), some individuals with different characteristics may be better suited to the new conditions and survive.
10
True
True. Fossils show life has changed over time, with many species different from those alive now.