Science for Kids - Mammals

Unless you live underwater in some vast ocean, you will find that everywhere you turn a mammal or two will be in sight! In fact, even if you do live underwater, you may run into a dolphin or a blue whale, evidence that the world of mammals is as extensive as it is varied. Teaching your children about this huge group of animals - which, by the way, includes us -is, therefore, pretty easy to do. So, why not take an opportunity to blend your lesson about mammals with some instruction on scientific observation? When scientists observe the animal, plant or mineral world, one very important thing that they always do is to record their observations. They will look at, listen to, smell and feel - only if this is all safe - the object or being that they are studying and make detailed observations.

Take your kids on a field trip - to the local zoo, farm, conservation area, or in some cases, wooded ravine - and teach them about recording the observations of the mammals that they encounter. All you need is a drawing pad, coloring pencils and binoculars. Be sure not to wear clothes that are too flamboyant as that may cause some shier mammals to run away. As your children spot various mammals, they can write, or draw what they notice about the animal, onto their paper and keep it to remind them what they've learned. The idea is to observe, and record, as many things as possible about each animal that you find while thinking about why they are grouped into the mammal category.

So what characteristics make a mammal?

First, all mammals, whether on land or in the sea, have hair or fur. (Even dolphins have hair around their mouths) The most important function of the hair or fur is to help the animal control its temperature. (Dolphins and other underwater mammals have a large layer of blubber under their skin for this purpose.) Mammals are warm blooded animals, which means they can adapt to cold or hot temperatures. Hair/fur helps them do this by trapping a layer of air close to the body to keep heat from slipping away. (Food energy is the other factor that keeps animals warm.) To cool down, different land mammals use different methods. Dogs stick out their tongues and breathe quickly when they get hot - air flows around their tongues and mouth and cools them down. (If your field trip is on a hot day, you can get your kids to count the number of panting dogs that they spot.) Horses, like humans, produce sweat to cool down. Mammals get bushier when it is cold and will shed hair when the weather becomes warmer. If you spot a squirrel on an autumn day in the park, you can have your child draw the squirrel, in his/her observation book, with an especially bushy coat.


Next, all land mammals have four limbs. (Underwater mammals, like whales, seals, dolphins, etc, of course, have fins.) Humans are the only mammal that always walks only on two limbs - other mammals sometimes walk on two limbs but will, at other times, revert to moving around on four. Mammals will primarily use the forelimbs, or arms, for gripping and holding food, cleaning and preening themselves or their young, digging, etc. The hind limbs are used as the major force when walking, trotting or running. While on your field trip, your children can observe some of the various things that different mammals do with their limbs. Also, does the mammal have claws, paws or hoofs? If claws or paws, how many fingers or toes do they have? If they are hoofs, do they have one toe or are they cloven into two or three toes? These are all different characteristics of the limbs of mammals. Each determines how the mammal gets around, eats or defends itself.

Third - and this one is trickier to spot - most mammals, except for two types, give birth to live young. That means, instead of being in an egg - which was laid by the female - and waiting for several days or weeks to hatch, the baby mammal is born already developed and alive.

The amount of time that babies spend in the mother's stomach - the gestation period - varies from species to species. The rat's gestation period is 21 days. For humans, we know that it is 40 weeks and for baby elephants, a 20 month stay in the womb is needed before they will venture out! Kangaroos, and other marsupials, will carry their live born young in a pouch on their bodies until they are big enough to survive in the outside world.

The only two mammals that lay eggs are ekidnahs - an ant eating mammal that looks a bit like a hedgehog and carries its eggs in a pouch on its body - and the platypus - a duck-billed mammal that can live underwater and lays eggs in a nest.

Mammals, more so than other animals, take relatively good care of their young. Mother mammals take the trouble to feed their young, clean them and protect them until the babies are ready to fend for themselves. (Baby elephants also receive care from another designated female elephant that is known as an 'aunt'!) In the animal kingdom, maturity is reached fairly quickly - often within weeks or months - as opposed to the human situation where raising children takes years! Have your child watch some mammals in a zoo and observe what the mothers do for their young. (Monkeys are always especially good subjects for this.)

The ONE thing that ALL mammals do, whether they live on land or under water - and this sets them completely aside from other animals - is that they feed their babies with milk from their own bodies! A farm, in the spring, is a great place to see this happening! Pigs, cows, goats, etc all can be found nursing their young. Mammalian milk is basically made from water and a collection of nutrients including proteins, fat, carbohydrates and vitamins. The proportions of these ingredients in the milk varies from one mammal to the other and depends on the animal's requirements within its habitat. When a mammal grows from its baby stages, it will, in terms of eating habits, become one of three things; an herbivore - eats just plants - a carnivore - eats meat which may include insects - or an omnivore - eats either.

One more thing that you can teach your children is that some mammals, that live in places where the temperature becomes very cold, will hibernate. This means that they sleep throughout the winter months, when food may be scarce, in order to conserve energy. Here's a tip for your field trip - don't bug animals that are in the process of hibernating - especially bears!! They'll be cranky and, don't forget, very hungry!

When your field trip is over, and you are back home talking with your kids about what they observed, why not share some of the following mammal trivia;
The largest mammal - and biggest animal in the history of the world - is the blue whale! Its length is 27m and it weighs 150 tons. The tallest, at about 20 meters in height, is the giraffe.

A baby kangaroo is called a joey and is the size of a bean when it is born and crawls into its mother's pouch.
Grey wales have the longest migration - moving from one place to another to feed or breed in desirable temperatures - of all animals; in one year they make a round trip of up to 20000km.
Female elephants - and not the males -are the herd leaders or matriarchs...males get pushed out to go live on their own.

And here's one for all of you to enjoy: humans are the only mammal that feeds on the milk of other animals!