Grade by Grade
B. Life Systems · Growth and Changes in Animals

Characteristics That Stay the Same and Characteristics That Change

B2.1 A1.2 A1.5About 35 minutes
Learning goals
  • I can name characteristics of an animal that stay the same for its whole life.
  • I can name characteristics that change as an animal grows or as the seasons change.
  • I can measure and record how something grows, and share what I found.

Words to know

constant
Staying the same. A constant characteristic does not change.
antlers
Bony branches that grow on the heads of deer, moose and caribou. Antlers fall off and grow back every year.
moult
To lose old fur or feathers so new ones can grow in.
shed
To let something fall off, like a snake's old skin or a deer's antlers.
measure
To find out how long, tall or heavy something is, using a tool like a ruler or a scale.
record
To write down or draw what you observe so you remember it.

Was that the same hare?

In July, Noah saw a brown hare hopping near the cottage. In January, he saw a white hare in the same spot. Was it a different animal?

Maybe not! A snowshoe hare has brown fur in summer and white fur in winter. It is the same animal. Some of its characteristics change, and some stay the same.

A white snowshoe hare with black ear tips sitting in the snow beside evergreen trees.
A snowshoe hare in its white winter coat. In summer this same hare will be brown. Its colour changes, but it is the same animal. AI-generated image
summer: brown furwinter: white fursame hare, two seasons
A snowshoe hare in summer and in winter. Its fur colour changes. Its long ears, big back feet and fur covering stay the same.

Characteristics that stay the same

Some characteristics are constant. They stay the same for the animal's whole life (after it is grown). For example:

  • the kind of body covering: a bird always has feathers, a bear always has fur
  • the number of legs (an adult insect always has 6)
  • the kind of animal it is: a moose calf grows into a moose, never into a deer

Characteristics that change

Other characteristics change:

  • Size and mass: Animals grow bigger as they get older.
  • Colour: A snowshoe hare, an Arctic fox and an ermine (a kind of weasel) turn white in winter and brown in summer. A white-tailed deer fawn is born with white spots that fade as it grows.
  • Antlers: Male deer and moose grow new antlers every year and shed them in winter. Caribou are special: both males and females grow antlers.
  • Coverings: Birds moult. They lose old feathers and grow new ones. A garter snake sheds its old skin as it grows. Dogs and cats shed fur in spring.
  • Teeth: You lose your baby teeth, and adult teeth grow in!
AnimalStays the sameChanges
snowshoe harefur covering, long ears, big back feetfur colour: brown in summer, white in winter
white-tailed deerfur, 4 legs, hoovesfawns lose their spots; males grow and shed antlers every year
garter snakescales, no legsgets longer; sheds its skin many times
robinfeathers, 2 wings, beakgrows feathers as a chick; the young robin's spotted chest turns red-orange as an adult
youhair, 2 arms, 2 legs, 10 fingersheight, mass, baby teeth fall out, hair gets longer
Some characteristics stay the same and some change
Worked example

Let's observe a white-tailed deer through the year

A male white-tailed deer lives near a farm. What changes and what stays the same during one year?

  1. Spring: New antlers start to grow. They are covered in soft, fuzzy skin called velvet.
  2. Summer: The antlers keep growing. His summer coat is reddish brown.
  3. Fall: The velvet comes off. The antlers are hard. His coat turns greyish brown and thicker for winter.
  4. Winter: He sheds his antlers. They fall off!
  5. All year: He still has fur, 4 legs, hooves and a white tail.

Changes: antlers and coat colour and thickness. Stays the same: fur covering, 4 legs, hooves, white tail.

Worked example

Let's measure how something grows

Ella wants to know how much her new puppy grows. How can she find out like a scientist?

  1. Ask a question: How much longer will my puppy get in 4 weeks?
  2. Choose a tool: a measuring tape. She measures from the nose to the start of the tail, in centimetres.
  3. Measure the same way every time: every Saturday, with the puppy standing.
  4. Record the numbers in a table: Week 1: 30 cm. Week 2: 32 cm. Week 3: 34 cm. Week 4: 36 cm.
  5. Look for a pattern: Each week the number goes up by 2 cm.

Her puppy grew 6 cm in 4 weeks (from 30 cm to 36 cm). Its length changed, but it still has fur, 4 legs and a tail.

01020304030 cmWeek 132 cmWeek 234 cmWeek 336 cmWeek 4length (cm)Ella's puppy, measured every Saturday
Ella's puppy grows 2 cm every week: 30, 32, 34, 36 cm. The bars get taller, but it is still the same puppy with the same fur and 4 legs.

Measure the same way every time

A fair measurement starts at the same place each time, uses the same tool, and uses the same units (like centimetres). Otherwise the numbers could change even if the animal did not grow!

Just for fun

Why don't snowshoe hares go shopping for winter coats?

They grow their own! Every fall a brand-new white coat comes in, free of charge.

Hands-on activity

Then and now

You need: a baby photo of you (or your baby clothes), a measuring tape, string, paper and a pencil.

  1. Lie on the floor. A grown-up marks where your head and feet are. Measure your height in centimetres. Record it.
  2. Measure a piece of your baby clothing, or look at your baby photo.
  3. Make a two-column chart: Stayed the same and Changed.
  4. Fill it in. Examples: Stayed the same: 2 eyes, 10 fingers, hair. Changed: height, number of teeth, hair length, what you can do.
  5. Share your chart with your family and tell them your most surprising change.

What to look for: at least 2 things in each column, and a real measurement with units (cm).

Your turn

1

What colour is a snowshoe hare in winter? In summer?

2

Name one characteristic of a robin that stays the same its whole life.

3

What happens to a male moose's antlers in winter?

4

A white-tailed deer fawn has white spots. Does it keep them forever?

5

Why does a garter snake shed its skin?

6

Name 2 things about you that have changed since you were a baby.

More practice: warm-up

1

Will a bear ever grow feathers?

2

Does a puppy get bigger or smaller as it grows?

3

What tool can you use to measure how long a puppy is?

4

What does moult mean?

5

How many legs does a grown-up ladybug have? Will that number change?

More practice: on your own

1

Sort these into stays the same or changes for an Arctic fox: fur colour, having 4 legs, having fur, size.

2

Caribou are different from deer and moose. How?

3

A kitten is 10 cm long. Three weeks later it is 16 cm long. How much did it grow?

4

Why do you think a snowshoe hare turning white in winter helps it?

5

Mila measured her puppy from the nose one week and from the ears the next week. Is that fair? Why?

Challenge

1

Liam finds a white bird in the snow in winter. In summer, he finds a brown bird of the same size and shape in the same place. Could it be the same kind of bird? What other clues should he look for?

2

A puppy measured 30 cm, 32 cm, 34 cm and 36 cm in four weeks. If it keeps the same pattern, how long will it be in week 5?

3

Is your name a characteristic that a scientist could observe? Explain.

Check your understanding

Quiz

1.

Which characteristic of a robin stays the same for its whole adult life?

2.

What colour is a snowshoe hare in winter?

3.

Which animal sheds its antlers every year?

4.

Why does a snake shed its skin?

5.

A puppy was 20 cm long. Now it is 25 cm long. How much did it grow?

6.

Which is the fair way to measure a growing puppy every week?

For parents and teachers

Big idea: Some characteristics are constant (type of body covering, number of legs, the kind of animal) and some change, either as the animal grows (size, spots, teeth) or with the seasons (coat colour, antlers, moulting). This completes the "constant and changing" part of B2.1.

Measuring (A1.2): Using a tape measure in centimetres, measuring the same way each time, and recording in a table are all part of the scientific experimentation process. Keep the numbers small and friendly.

Accuracy notes: In white-tailed deer and moose, only males grow antlers; in caribou, both males and females do. Antlers are shed and regrown every year (horns, like a bighorn sheep's, are not shed).

Common difficulties:

  • Thinking a white hare and a brown hare must be different animals. Point to the characteristics that stayed the same.
  • Mixing up "growing" with "changing into a different animal". A calf always grows into the same kind of animal (frogs and butterflies are coming up later in the unit!).

How to help: Mark your child's height on a door frame and measure again in a few months. Look for deer, hares or birds on walks and talk about what might look different in another season.