Animals & Nature · Unit 15

Animal Evolution

Adaptation, natural selection, and how animal groups are related

Every feature in every earlier unit is the outcome of the process covered here, and seeing that turns a collection of facts into a single explanation.

The unit covers adaptation, natural selection, the fossil and anatomical evidence, convergent evolution - where unrelated animals arrive at the same solution - and domestication as selection with a human doing the selecting.

This unit breaks down into 20 short steps and 117 questions, starting at difficulty 2 and building to 4. Below you can see exactly what it covers, how the path is structured, and worked examples with explanations.

Steps: 20
Questions: 117
Difficulty: 2-4

What this unit covers

Adaptation
Natural Selection
Convergent Evolution
Domestication and Breeding
Evidence from Fossils and Bodies

Where this fits

Best after the class units. Overlaps with Biology's Evolution and Ecology.

Where people slip

Convergence is the trap in classification. Dolphins and sharks look alike because they solve the same problem, not because they are related.

How the unit is structured

Animal Evolution runs as 20 short steps that unlock in order. 15 are practice rounds and 5 are challenge rounds that pull together everything before them. Questions start at difficulty 2 and climb to 4 as you progress.

Step 1 · easierStep 20 · harder

Challenge rounds

Example questions

30 real questions from this unit, with the answer and the reason behind it, grouped by what they practise. There are 117 in the unit altogether.

Adaptation

Choose all that applyLevel 2
1. Which are adaptations for flight? Pick all that apply.
- Hollow light bonescorrect
- Featherscorrect
- Powerful chest musclescorrect
- Heavy solid bones
Light bones, feathers and strong chest muscles all aid flight.
True or falseLevel 2
2. Webbed feet help ducks swim.
Answer: True
True. They push more water with each stroke.
Multiple choiceLevel 2
3. What is an adaptation?
- A feature that helps an animal survive where it livescorrect
- A choice an animal makes
- A place an animal visits
- A kind of food
An adaptation is a feature that helps an animal survive and reproduce where it lives.
Multiple choiceLevel 3
4. How does a giraffe's long neck help it?
- It reaches food other animals cannotcorrect
- It helps it swim
- It keeps it warm
- It helps it dig
It can reach leaves that shorter animals cannot.
Type the answerLevel 3
5. What word describes a body feature that suits an animal to its habitat?
Answer: adaptation
An adaptation improves survival chances.
Choose all that applyLevel 3
6. Which show that evolution works with what is available? Pick all that apply.
- The long detour of the recurrent laryngeal nervecorrect
- Vestigial hip bones in whalescorrect
- Back problems from upright walkingcorrect
- Perfectly optimal design in every species
Awkward nerve routes, vestigial parts and imperfect joints all show constraint.

Convergent Evolution

Choose all that applyLevel 2
7. Which pairs show convergent evolution? Pick all that apply.
- Dolphin and shark body shapecorrect
- Bird wings and bat wingscorrect
- Cactus and euphorbia spinescorrect
- Lion and tiger stripes and manes
Each pair evolved similar traits independently.
Type the answerLevel 2
8. What word describes unrelated animals evolving similar solutions?
Answer: convergence
Convergence produces look-alikes from different lineages.
Multiple choiceLevel 2
9. What is convergent evolution?
- Unrelated species evolving similar featurescorrect
- Related species becoming different
- Species swapping habitats
- Species becoming extinct
Unrelated species developing similar features because they face similar challenges.
Multiple choiceLevel 3
10. Why do dolphins and sharks look similar despite being very different animals?
- Both evolved streamlined shapes for swimmingcorrect
- They are closely related
- Dolphins are fish
- They are the same species
Both evolved streamlined shapes for fast swimming, a case of convergent evolution.
True or falseLevel 3
11. Wings evolved separately in insects, birds and bats.
Answer: True
True. Each group solved flight in its own way.
Choose all that applyLevel 3
12. Which are classic examples of adaptive radiation? Pick all that apply.
- Galapagos finchescorrect
- Hawaiian honeycreeperscorrect
- African lake cichlidscorrect
- Domestic cats worldwide
Galapagos finches, Hawaiian honeycreepers and cichlid fish all radiated rapidly.

Domestication and Breeding

Build the sentenceLevel 2
13. Build a sentence about evolution.
Answer: Living things change slowly over many generations
Living things change slowly over many generations.
Choose all that applyLevel 2
14. Which animals have been domesticated? Pick all that apply.
- Dogcorrect
- Sheepcorrect
- Chickencorrect
- Tiger
Dogs, sheep and chickens all come from wild ancestors.
Fact or fibLevel 3
15. Individual animals evolve during their own lifetimes.
Answer: False
False. Populations evolve across generations, not individuals within a life.
Multiple choiceLevel 3
16. Why do many domestic animals look different from their wild ancestors?
- Generations of breeding changed their featurescorrect
- They painted themselves
- They changed during one lifetime
- They are unrelated to wild animals
Generations of breeding for tameness, size or appearance changed them.
Put in orderLevel 3
17. Put these steps of natural selection in order.
Answer: Individuals vary -> Some survive better in their environment -> Survivors reproduce more -> The helpful trait becomes more common
Variation exists, some survive better, they reproduce, and the trait spreads.
Sort into groupsLevel 3
18. Sort each feature as a body adaptation or a behaviour adaptation.
Answer: Thick winter fur = Body adaptation; Webbed feet = Body adaptation; Migrating in autumn = Behaviour adaptation; Hunting at night = Behaviour adaptation
Adaptations can be physical or behavioural.

Evidence from Fossils and Bodies

Choose all that applyLevel 2
19. Which are evidence for evolution? Pick all that apply.
- Fossils in rock layerscorrect
- Shared skeleton patternscorrect
- Similarities in DNAcorrect
- The colour of the sky
Fossils, shared body plans and DNA comparisons all provide evidence.
Multiple choiceLevel 3
20. What is a fossil?
- Preserved remains or traces of ancient lifecorrect
- A modern bone
- A type of rock with no life in it
- A kind of shell used as money
The preserved remains or traces of a living thing from long ago.
True or falseLevel 3
21. Tiktaalik shows features of both fish and early four-limbed animals.
Answer: True
True. It had a neck, sturdy fins and a flat head.
Type the answerLevel 3
22. What is the study of fossils called?
Answer: palaeontology
Palaeontology reconstructs ancient life.
Choose all that applyLevel 3
23. Which support common ancestry? Pick all that apply.
- A shared genetic code across lifecorrect
- Similar early embryoscorrect
- Homologous limb bonescorrect
- Identical adult body sizes
Shared genetic code, similar embryos, homologous bones and pseudogenes all support it.
Multiple choiceLevel 3
24. How does DNA comparison support the tree of life?
- Anatomical and genetic relationships agreecorrect
- DNA contradicts all fossils
- All species have identical DNA
- DNA cannot be compared
Species that appear closely related by anatomy also share more DNA sequence.

Natural Selection

Choose all that applyLevel 2
25. Which are needed for natural selection to work? Pick all that apply.
- Variation between individualscorrect
- Features passed to offspringcorrect
- Some individuals surviving bettercorrect
- All individuals being identical
Variation, inheritance and differences in survival are all required.
Type the answerLevel 2
26. What is the process by which better-suited animals survive and pass on their features called?
Answer: natural selection
Natural selection acts over many generations.
Multiple choiceLevel 2
27. Who is best known for explaining evolution by natural selection?
- Charles Darwincorrect
- Isaac Newton
- Galileo Galilei
- Louis Pasteur
Charles Darwin published his theory in 1859.
Multiple choiceLevel 3
28. Why are individuals within a species not all identical?
- They inherit different combinations of featurescorrect
- They choose their appearance
- They all live in different places
- They are identical really
Variation comes from inherited differences and small changes in genes.
True or falseLevel 3
29. Animals born with useful features are more likely to survive and have young.
Answer: True
True. That is the core of natural selection.
Choose all that applyLevel 3
30. Which are mechanisms of evolutionary change? Pick all that apply.
- Natural selectioncorrect
- Genetic driftcorrect
- Gene flow between populationscorrect
- Individual practice and training
Natural selection, drift, mutation and gene flow all change populations.

Where these questions come from. Each unit starts as a plan of the concepts it should cover and the difficulty it should span. Questions are written against that plan with AI assistance, then checked by a validator that rejects anything without a single defensible answer, an explanation, or plausible wrong options. How we write questions sets out the whole process, and corrections are fixed in the bank and reach the site and the app the same day.

How you practise

This unit mixes 8 different question formats, so you are recalling and applying rather than recognising the same layout every time.

Build the sentence
Choose all that apply
Fact or fib
Multiple choice
Put in order
Sort into groups
True or false
Type the answer

Practise Animal Evolution

117 questions across 20 steps. Start with step one and crawl at your own pace.

Play this unit

Read about Animal Evolution

Explainers from our blog on what this unit covers. Each one ends with real questions from the bank.

More units in Animals & Nature

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