ACARA v9 CONTENT DESCRIPTION “examine how particular structural features and behaviours of living things enable their survival in specific habitats”
Builds on grouping living things by what they look like and where they live. Here we look at the particular features and behaviours a living thing has, and how each one helps it survive in its own habitat.
Features that suit a habitat
A habitat is the place where a living thing makes its home, such as a hot desert, a freezing coast or dry rocky ground. Each living thing has particular features that suit its own habitat. A camel has wide flat feet and a fat hump that suit the desert. A penguin has thick blubber and stays in a close huddle to suit the cold. A cactus has spines and a thick stem that store water on dry ground. The feature fits the place, so the living thing can survive there.
Match the feature to its home
Each living thing has a feature that suits one habitat. Pick an animal and see the home it fits.
A camel has wide flat feet and a fat hump that suit the hot sandy desert. A penguin has thick blubber and huddles close to stay warm on a freezing icy coast. A cactus has spines and a thick stem that store water on dry rocky ground. Each feature helps that living thing survive in its own habitat.
Structural and behavioural features
A living thing can survive through two kinds of feature. A structural feature is part of its body, like thick fur, webbed feet or sharp claws. A behavioural feature is something it does, like huddling together, coming out only at night, or migrating away in winter. Both kinds help the animal cope with its habitat. When you look at an animal, ask whether each feature is a body part or a thing it does.
Sort: body part or action?
A structural feature is part of the body. A behavioural feature is something the animal does. Sort each one.
A structural feature is part of the animal's body, like thick fur, webbed feet or sharp claws. A behavioural feature is something the animal does, like huddling together, coming out at night or migrating in winter. Both kinds of feature help an animal survive in its habitat.
A feature can help an animal survive
You can see how much a feature matters by imagining it switched off. A desert lizard can burrow into cool sand to escape the worst heat of the day. With that behaviour, it stays cool and survives. Without it, the lizard sits in the burning sun and overheats. The feature is doing real work, helping the animal get through the conditions in its habitat.
Switch the feature on and off
A desert lizard can burrow into cool sand to escape the heat. Turn that behaviour on and off.
In the hot desert, a lizard can burrow down into cool sand to escape the midday heat. With that behaviour switched on, it stays cool and safe and its chance of survival is high. With it switched off, the lizard sits in the burning sun and overheats. The behaviour helps the lizard survive in this habitat.
The right feature for the right place
A feature only helps in the habitat it suits. A polar bear's thick blubber keeps it warm on a freezing coast. Put that same bear in a hot desert and the thick blubber traps too much heat, so it overheats. The feature did not change, but the habitat did. This shows that a feature helps survival only when it matches the place the animal lives in.
The wrong habitat
A polar bear's thick blubber suits the cold. Move it to a hot desert and watch the feature stop helping.
A polar bear's thick blubber keeps it warm on a freezing icy coast, so its survival is high there. Move the same bear to a hot desert and that thick blubber traps too much heat, so it overheats. A feature only helps in the habitat it suits. In the wrong place, the very same feature can be a problem.
Every feature has a job
Each feature does a clear job that helps the animal live where it does. A honeyeater's long thin beak reaches deep into flowers to sip nectar that other birds cannot get. A duck's webbed feet spread wide to push against the water so it can swim. The shape of the feature matches the job it needs to do, which is why it is so useful in that habitat.
A feature with a job to do
Each feature does one clear job that helps the animal live in its habitat. Choose a feature.
Every feature has a job. A honeyeater's long thin beak reaches deep into a flower to sip nectar that other birds cannot get. A duck's webbed feet spread wide to push against the water, so it can swim. The shape of the feature matches the job it needs to do in that habitat.
Why this matters
Looking closely at features and behaviours helps you understand why animals and plants live where they do. A camel belongs in the desert and a penguin on the ice because their features suit those homes. This way of thinking helps you make sense of the living things around you, and gets you ready for more science about habitats, food and how living things depend on their environment.
Quick self-check
1. A camel has wide flat feet and a fat hump. Which habitat do these features suit?
2. Which of these is a behavioural feature rather than a structural one?
3. A desert lizard burrows into cool sand at midday. What does this behaviour do for it?
4. A polar bear with thick blubber is moved from the icy coast to a hot desert. What happens?