KS3 · Biology

Adaptations of organisms to their environment

Same moths, different tree, different winner. When the trunk was sooty, dark moths blended in. When it turned pale, light ones did. How can that happen?

Biology · Adaptations

Cold or hot? Sort the features

Where would each feature help an animal most: the cold Arctic, or the hot, dry desert?

Still to sort

Cold Arctic (0)

Heat is precious here.

Where the line is: In the cold, the jobs are keeping heat in and blending in against snow.

Hot, dry desert (0)

Heat is the problem, and so is water.

Where the line is: In the hot, dry desert, the jobs are letting heat out, blending in against sand and saving water.

10 of 10 still to sort.

Two foxes, two very different homes. Pick a feature, pick the place it suits, then read why. Watch for one idea turning up again and again.

Watch out: Every feature here suits exactly ONE of the two places. 'Good for survival' is not an answer on its own: ask what job the feature does there.

Biology · Adaptations

Move a well-adapted organism. What happens?

A shark is lifted out of the sea and put down in a forest. Then picture a cactus whose desert habitat turns to snow.

Which is closest to what you think would happen?

They are well adapted, so they are just tough. They will be fine wherever they end up.They will simply adapt to their new surroundings and carry on.Their adaptations are specific to their original environment, so they would struggle in the new one.

How sure are you?

I'm sureI think soI'm guessing

They are well adapted, so they are just tough. They will be fine wherever they end up.

This is a common misconception

Tempting, because 'adapted' sounds like 'built to last'. But an adaptation is a feature that suits one environment. The shark cannot take in oxygen from air, and the cactus would not do well in snow. Take away the environment and the adaptation stops doing its job.

They will simply adapt to their new surroundings and carry on.

This is a common misconception

It feels like they should adjust, but that is not how adaptation works. Their features were suited to the old environment, and in the new one they are no longer the right ones. A change in the environment can leave individuals, or a whole species, less well adapted. That is where extinction can come in.

Their adaptations are specific to their original environment, so they would struggle in the new one.

This matches the evidence

Yes. Being well adapted is a match between an organism AND a particular environment. Change the environment and the match can break: the shark cannot take in oxygen from air, and the cactus would not do well in snow.

'Well adapted' always means well adapted TO somewhere. Adaptations are specific to an environment and do not work in a different one.

Animals and plants: different jobs, different rivals

AnimalsvsPlants

Read across each row. What is each group up against?

Focus

What they compete for

Animals

Food, water, shelter and mates

Plants

Water, space, light, minerals, pollinators and seed dispersers

The insight

Only water is on both lists. Mates, shelter and food belong to the animal list. Light, minerals, pollinators and seed dispersers belong to the plant list.

What their adaptations tend to help them do

Animals

Hunt prey or avoid predators

Plants

Carry out as much photosynthesis as possible

Example features

Animals

Camouflage, and body features that keep heat in or let it out

Plants

Chlorophyll, broad and thin leaves, thorns, flowers and fruit

In a dry place

Animals

Desert animals make small amounts of concentrated urine, which saves water

Plants

A cactus shows plant adaptations to a dry place

Competition and fitness

Reason it through

Why do some individuals in a habitat do better than others?

Link 1 of 4

First link · your turn

Is there enough food, water, space and light in a habitat for every organism to have as much as it wants?

Locked — reveal the link above first

Biology · Adaptations

Same moth, different tree: who wins?

Pick a condition of the tree bark. Which moths are camouflaged, and what happens to them?

Tree bark → Which moths are hidden

2 possible outcomes for the moth population.

On Peppered moths on tree bark. 2 branches to choose from.

The peppered moth shows what happens when the environment changes. Choose the tree bark and see which moths come out on top.

Watch out: Neither colour of moth is 'the good one'. It all depends on the bark.

Biology · Adaptations

Write it, then mark it

Explain how a change in the environment can lead to a species becoming extinct. Use an example from this lesson. [4 marks]

Your answer

0 words · your answer stays on this page and is not sent anywhere.

The mark scheme

Individuals that were well adapted before the change become less well adapted after it (for example, a cactus whose habitat turns to snow) (1 mark)
They are less able to compete and so less likely to reproduce (1 mark)
If the whole species is affected, it may die out (1 mark)
Extinction is the permanent loss of a species (1 mark)

Model answer

If the environment changes, individuals that were well adapted can become less well adapted, like a cactus whose desert habitat turns to snow. Being less well adapted, they are less able to compete and less likely to reproduce. If the whole species is affected, it may die out completely. That permanent loss of a species is called extinction.

Environment changes, fitness changes, and a species that cannot cope may be lost for good. Name the change, then say what it does to how well adapted the organisms are.

WHAT YOU'VE LEARNED

A quick recap of today's lesson.

What you need to know

Animals and plants are adapted to their environments, and an adaptation only works in the environment it suits.
Arctic fox adaptations: small ears, white fur, thick coat and fat layer, foot pads, short thick limbs and greasy fur. Fennec fox adaptations: large ears, sandy fur, short coat and long thin limbs. Desert animals may be nocturnal or crepuscular and make small amounts of concentrated urine.
More surface area means more heat lost. That one idea gives small ears in the cold and large ears in the heat.
Animals compete for food, water, shelter and mates. Plants compete for water, space, light, minerals, pollinators and seed dispersers.
The best adapted individuals, the fittest, are more likely to compete successfully, survive and reproduce. The less fit are more likely to die before reproducing.
A change in the environment can leave individuals, or a whole species, less well adapted, which may lead to extinction.

The big picture

Animals and plants are adapted to the environments they live in, and an adaptation only works in the environment it suits. Adaptations give an advantage in competition, and a change in the environment can leave individuals or a whole species less well adapted, which may lead to extinction.

Key points

1Adaptations are specific to an environment: a feature that helps in one place can fail in another.

2Heat, camouflage and water saving are three jobs adaptations do. More surface area means more heat lost.

3Limited resources mean competition. Variation means some individuals have an advantage, and the fittest are more likely to survive and reproduce.

4When the environment changes, who is well adapted can change too, as the peppered moth shows.

5Extinction is the permanent loss of a species.

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Worked example

Problem

A fennec fox is moved from the desert to the Arctic. Explain why its large ears are a poor feature there.

⚠ Watch out

Thinking a well-adapted organism will do well anywhere, or will simply change to fit a new environment. Adaptations are specific to an environment, and a change in the environment can leave individuals or a whole species less well adapted.

🧠

Memory hook

Same rule, opposite answers: more surface area means more heat lost. Big ears for the hot desert, small ears for the cold Arctic. And 'adapted' always means adapted TO somewhere.

✓

Check yourself

Cover the page. In two sentences, explain why small ears help an animal in the cold, and why that same idea explains large ears in the desert.

Flashcards

(14)

More surface area means what for heat?

More heat is lost. Small ears and short, thick limbs lose less (cold). Large ears and long, thin limbs lose more (hot).

What is camouflage? Give two examples from the foxes.

Colouring that helps an animal blend into its background. White fur blends into snow (arctic fox). Sandy fur blends into sand (fennec fox).

Name the arctic fox's adaptations.

Small ears, white fur, thick coat and fat layer, foot pads, short thick limbs and greasy fur.

Name the fennec fox's adaptations.

Large ears, sandy fur, short coat and long thin limbs.

Two ways desert animals cope with the desert?

They are nocturnal or crepuscular, and they make small amounts of concentrated urine to save water.

Why would a shark do badly in a forest?

Its adaptations are for the sea. It cannot take in oxygen from air, so they do not work in a different environment.

What do animals compete for?

Food, water, shelter and mates.

What do plants compete for?

Water, space, light, minerals, pollinators and seed dispersers.

Which plant adaptations help with photosynthesis?

Chlorophyll, and broad, thin leaves, so the plant can carry out as much photosynthesis as possible.

What does variation give some individuals?

Adaptations that give them an advantage when competing.

Who are 'the fittest'?

The best adapted individuals. They are more likely to compete successfully, survive and reproduce.

What happens to the less fit?

They are more likely to die before they reproduce.

What happened to peppered moths when the Clean Air Act cleared the trees?

In the 1800s, dark bark made dark moths camouflaged and more common. After the 1956 Clean Air Act and other measures, lichen regrew and light moths became more common again.

What is extinction?

The permanent loss of a species.

Tap any card to flip it, or use Study as deck to go through them one at a time. In the full lesson these run as a spaced-repetition deck — you rate each card Hard, Good or Easy and the tricky ones keep coming back until they stick.

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Cold or hot? Sort the features

Move a well-adapted organism. What happens?

Same moth, different tree: who wins?

Write it, then mark it

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