MAMMALIAN MODIFICATIONS

MAMMALIAN MODIFICATIONS

The modifications between mammals may be, 

a. BEHAVIOURAL such as hunting by groups instead of  Hunting individually;

b. PHYSIOLOGICAL such as the ability to conserve  Water;

c. STRUCTURAL such as to allow them to live in water   Or fly.

We said that all mammals have some qualities in common, they are:

1. They suckle their young ones with milk.

2. They all breathe and have lungs to respire.

3. All of them are more or less covered with hair.

4. All of them are WARM BLOODED animals; that is to say that their blood is warm and stays in their body at constant temperature.

MAMMALS

Look at the picture given.

The three animals are entirely different in their appearance;

a bat , a seal and a cow. But they all belong to the same class of Animal Kingdom, the MAMMALS.

The reason they are grouped together is that, they have the four common characteristics as described above.

In fact mammals are far more diverse (looking different) than what the picture shows.

There are mammals living on land, in trees, under ground, in fresh water, and in the sea.

There are mammals that can run, jump, swim, fly and even read and write!

Do you know that we human beings our self are mammals.

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 Some mammals are carnivorous (flesh-eaters) and some are herbivorous (vegetable-eating) like grandpa and some others like us are omnivorous (eat both flesh and vegetables)

Even though many other animals do have lungs; and the blood of birds are warm, they are not called mammals.

THE HAIR ON THEM AND THE MILK, ON WHICH THEY SUCKLE THEIR YOUNG ONES,

 DISTINGUISH THE MAMMALS, FROM ALL OTHER ANIMALS.

Let us see the modifications described above one by one.

a.  BEHAVIOURAL such as hunting by groups   instead   of   hunting individually.

Some animals like Tigers, Leopard, and Bear etc. hunt individually. They go alone and hunt for their food. After getting their food, they eat alone. In the case of Lion, the lioness (female lion) will collect group lionesses and hunt together.

But some animals like lion, whistling wild dogs hunt as a team. You may take the example of ants, bees also. Ants and bees bring food and store at their home for every one including the new born to use.

Cattle, deer, sheep, giraffe, zebra all go as groups to graze in grass lands. You may call them as living in groups or sociable animals or GREGARIOUS animals. Human beings also are GREGARIOUS!

REMEMBER! ALL THE ANIMALS DESCRIBED ABOVE ARE MAMMALS

b. PHYSIOLOGICAL such as the ability to conserve water.

 

For example Camels have hump to conserve water , Polar Bears have thick fur to protect them from cold.

c. STRUCTURAL such as to allow them to live in water or fly.

The Blue Whales, the Seals (Sea lions), the PLATYPUS and the HIPPOPOTAMUS all have their body structure modified to live in water. The whale, seal and platypus have streamlined body to swim while the Hippos have soft skin with less hair to live in water. 

Hippopotamus is a strange mammal. It lives during the day in the river waters and feeds on grass on land during night.

Like wise the Platypus is another strange animal too. It also lives in a tunnel made on the river banks and feeds on aquatic insects. For the most part of its life it lives in water.

Some mammals do fly, like BATS. It is interesting to note that no bat flies during the day. But very few birds like owl fly during the night. Even though they eat the same type of food; they do not fight among them selves for food.

’ Many wars among human beings have been waged for better lands, where food could be grown’.

It is difficult to see on earth, animals that do not fight for food.

Fact remains that Bats are flying mammals. We shall see in detail about bats shortly.

HIPPOPOTAMUS

The hippopotamus is popularly known as the “RIVER HORSE”; because it lives mostly in African rivers. But it is not correct to call it a horse. It never resembles a horse. Perhaps if it could have been called as “RIVER PIG”, it may be correct; for it resembles more like a pig. Pigs have four toes just like the hippos. But the hippo’s toes have large nails and are webbed for swimming. Both have similar structure of teeth.

The hippos are powerful swimmers and can easily swim even against the current of water. Some times it walks at

the bottom of rivers. Even though it looks very fat, it does not have much of fat. Its body is mostly made up of meat.

During the day the hippos often look to be sleepy. This is because, hippos are nocturnal (active by the night) animals. Their staple food is grass. But they are known to eat corn or even sugar cane. In the wild it causes damage to these crops. In the night it goes for grazing and returns at dawn with stomach full of grass. It spends the day digesting the grass.

 

Do you know that the baby hippos (calf) are born under water? These calves ride on the back of their mother while in water for almost one year.

Well! Don’t you think the hippos are strange mammals?

PLATYPUS

Australia is a strange continent by itself as it has been isolated as an island for a very long time. The land of Kangaroos has lots of strange stories. Some of them are really true. So is the story of the EGG LAYING MAMMAL.

In the late 18th   century, travellers from Australia brought an animal fur (hairy skin of animals) to the market. It reached the hands of a few NATURALISTS in Europe. The fur of this creature was like that of a mammal with a lot of hair; but instead of a mouth it had beak, looking like a Duck’s bill. Some of the scientists refused to believe that such an animal could exist. They said that whoever has brought the fur has made up the animal by joining the parts of a mammal and a bird.

Later a few scientists who travelled from Australia brought the whole animal preserved in Alcohol and made the Naturalist in Europe believe the existence of the strange animal.

This strange animal is called PLATYPUS .The animal looked half way between that of a mammal and that of a reptile. Perhaps it is by chance its beak looked like that of a duck. Investigations on the animal showed that it laid eggs like a bird or a reptile; but suckled its young ones like a mammal. We can call this extraordinary mammal as PRIMITIVE MAMMAL.

The home of the platypus is the long tunnel it digs on the banks of a river, a pond, or a lake. The tunnel opens under water. It stays in the long tunnel all day and comes out during the evening. It feeds on aquatic animals including small fish.