This edited article about strange creatures originally appeared in Look and Learn issue number 702 published on 28 June 1975.

Pangolin

In the world of nature, there are many very strange creatures, both in appearance and behaviour. Some have adapted themselves to living in very extraordinary situations. For instance, some exist in the hot water springs in New Zealand, and in pools of oil and in deep caves where no light ever enters and these, in course of time, have become completely blind.

One of the oddest of all mammals is the Pangolin. Looking more like a reptile, with hard scales, instead of hair, it feeds chiefly on ants and termites and has a tongue nearly a foot (304.8000 mm.) long. When alarmed, it rolls up into a ball rather like a hedgehog.

The Kiwi is a native of New Zealand. About the size of a large hen, its wings are only 2 inches (50.800 mm.) long, so it cannot fly. Most birds have a very poor sense of smell, but the kiwi, with nostrils near the tip of its bill, has such a good sense of smell that it tracks its prey, consisting of worms and insects, mainly by smell. Its egg is enormous in relation to its size.

The reptile and amphibian species contain some of the most extraordinary creatures. The Basilisk, about 2 feet long, looks like a miniature dragon and is also remarkable because it can run at a great speed on the surface of water; but when it tires and the pace slackens, it sinks until only its head is above water and it has to swim.

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This edited article about longevity in nature originally appeared in Look and Learn issue number 700 published on 14 June 1975.

Giant tortoise

A cone fell from a tree in Nevada, U.S.A. nearly five thousand years ago, took root and began to grow. Today, it has developed into a magnificent bristlecone pine tree and is the oldest thing alive.

Scientists dated it in the early sixties, probably by cutting a core through to the heart of the trunk and counting the rings revealed in this.

When a tree is cut down, the concentric rings across the trunk reveal the age of the tree, each ring representing one year’s growth. One bristlecone pine that had been felled was found to have five thousand rings, showing that it had begun growing at about the time the ancient Egyptians started to build their pyramids.

The surviving bristlecone pine, however, sprouted into life when the pyramids were already desert land marks 4,900 years ago. It is even older than the giant sequoia, known as the California big tree, which has a life span of between 3,500 and 4,000 years.

Compared to these, longevity in the animal kingdom is an insignificant thing. No creature’s average age is longer than that of Man’s. Few people live beyond the age of 110, although the average age is nearer seventy. Man’s closest rival is the tortoise, which holds the record for long life among the vertebrates. A common box tortoise has lived to become 138 and a European pond tortoise more than 120.

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This edited article about nature’s smallest animals and plants originally appeared in Look and Learn issue number 699 published on 7 June 1975.

Pygmy shrews

Our smallest native bird is the Goldcrest, but this is a giant compared with the world’s smallest bird the tiny Bee Humming Bird, found in Cuba and Ecuador. It gets its name because it is no bigger than a large bumble bee.

Its wings beat so fast that they are just a blur when it hovers in front of a tropical flower, its long beak dipping into the nectar in quest of nourishment. The adult females are slightly larger than the males.

Our smallest animal is the Pygmy Shrew, at two and one quarter inches, (57 mm), slightly smaller than the long-tailed Harvest Mouse. Even smaller is the Etruscan Shrew with a body length of only 1 and a half inches (38 mm) and reputed to be the smallest animal in the whole world.

Apart from animals, there are also a great number of microscopic insects. Some of these are so minute that they are scarcely visible to the naked eye.

The Dwarf Beetle, for instance, is small enough to pass through the eye of a small needle. The Small Blue Butterfly, less than 1 and a quarter inches (about 25 mm), across the wings, is the smallest British butterfly.

Unlike most of its kindred, it is only on the wing during the months of May and June.

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This edited article about animal intelligence originally appeared in Look and Learn issue number 699 published on 7 June 1975.

Tea for four chimps at the zoo by James E McConnell

When, at a very early age, we stood upright and hesitatingly took our first few steps, our parents were probably very proud of us.

After all, we had been trying to walk for quite a number of months. We learned how to crawl and use our complicated system of muscles. Finally came the most difficult lesson of all – standing on two feet and walking.

But let us think about what happens a few minutes after a foal is born. The frail little creature makes a few jerky movements, staggers up on its four spindly little legs – and then walks almost perfectly!

The ability of animals to do many complicated things without apparently having to learn them is called instinct.

Biologists are not at all certain exactly how these animal instincts or “built-in skills” have come about.

In fact some scientists are beginning to think that some instincts are not really built-in at all. Instead of the skill being inherited from the animals’ parents, it might still have been learnt.

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This edited article about the sense of smell originally appeared in Look and Learn issue number 697 published on 24 May 1975.

Bottles of perfume

When anyone talks about a “keen sense of smell” we often think of dogs in general – and bloodhounds in particular.

Yet in spite of the fact that smell is the weakest of our five senses, human noses can detect very small traces of certain chemical odours, even if they are in the air with a concentration of less than one part in a million.

Our ability to smell begins with the nostrils. These lead into what is called the “nasal cavity” which is lined, at its top part, with thousands of olfactory (smell-detecting) cells. From these cells nerve fibres lead to the brain.

When air is breathed into the nasal cavity, any gases, dust particles or traces of vapour in the air irritate the sensitive olfactory cells, which then send “odour messages” to the brain.

Many substances, of course, do not affect the olfactory cells so that we cannot smell them. Water vapour and air itself are good examples.

Because these don’t cause odour messages to be sent to the brain, we simply say they are “odourless” or don’t smell.

In general, we tend to divide odours into two kinds – pleasant and unpleasant. Most of us agree that the smell of a rose is pleasant, but that the odour of decaying food is not.

But sometimes it can be a matter of opinion – some people get quite ill when they smell lavender-scented soap while others like the smell of ripe gorgonzola cheese!

Most things have a characteristic odour because of some chemical substance they contain. It is this chemical which acts upon the olfactory cells in the nasal cavity and produces the “smell” sensation.

The familiar odour of bananas, for example, is caused by a pale yellow liquid chemical called amyl acetate which is present in the fruit.

The bad smells from decaying food are caused by certain gases, like phosgene, from decaying fish, and hydrogen sulphide from rotten eggs.

Our olfactory cells are really sensitive chemical laboratories which analyse separate smells.

The most pleasant odours are often a mixture of many chemical substances. Modern perfumes can contain more than two hundred chemicals, all expertly blended together.

This edited article about human biology originally appeared in Look and Learn issue number 696 published on 17 May 1975.

A Barnum and Bailey tight-rope artiste

Being able to keep upright is called “balance” or, as scientists say, “maintaining equilibrium.” We can do this because nature has provided us with two built-in “spirit levels.”

The ordinary spirit level consists of a glass tube containing a liquid. The tube is not quite full, so that a bubble of air floats in it.

When the spirit level lies flat, the air bubble is in the centre of the tube. Tip the tube to the right, the bubble moves to the left; tip it to the left, the bubble moves to the right.

But once the tube has been tipped, it must be moved by someone before the bubble is level.

The “spirit levels” in our ears do much better than that. If we tip backwards or forwards or to the right or left, they automatically bring us level again.

Each “spirit level” consists of three semicircular canals, containing a fluid, and an hour-glass shaped organ. The upper part of the “hour-glass” is called the utriculus and the lower part is the sacculus.

The fluid in the canals tends to stay still, but if we move our head it moves and bumps against nerves at the end of each canal. This causes a nerve message to be sent to the brain, telling us how much and in what direction our head has moved.

Inside the utriculus and sacculus are tiny pendulums of crystal suspended from very fine hairs.

If our body gets into a position from which we are in danger of losing our balance and so toppling over, the pendulums swing with it and bump against nerves. These instantly send a message to the brain warning of the danger.

The brain then causes return messages to be sent to the nerves and muscles controlling the movements to restore our balance. In this way the combined actions of the pendulums and of the fluid in the canals enable us to keep our balance.

If you keep twisting your body round and round you will feel giddy and lose your sense of balance. This is because you have churned up the fluid in the canals and put your “spirit levels” out of action.

This edited article about Ivan Pavlov originally appeared in Look and Learn issue number 693 published on 26 April 1975.

A pictorial diagram of the brain showing the nervous system

If you accidentally touch something hot, such as a stove, you immediately pull your hand away. You do this because of an automatic movement called a reflex.

You don’t think about the pain you feel and then decide to pull your hand away. Pulling your hand away just happens – long before you are really aware of the fact that you are hurt.

Other examples of reflex action are when your eyes water and you blink your eyelids if a speck of dust blows into the eye.

Reflexes also come into action if a light is suddenly shone at you. The pupils of the eyes immediately become smaller and you automatically close your eyelids.

If you see or smell some very attractive food, reflexes cause your mouth to water. Sometimes reflexes are strong enough to cause mouth watering at the very thought of food!

You do not even need to be awake for reflexes to get to work.

Tickle the sole of a sleeping person’s foot, and he or she immediately pulls the tickled foot away.

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This edited article about the sense of taste originally appeared in Look and Learn issue number 691 published on 12 April 1975.

The candy floss seller at the fairground

Since the earliest times, people have pandered to their sense of taste. Taste is one of the five senses – the others are sight, touch, smell and hearing.

Yet in spite of the thousands of differently flavoured dishes prepared by cooks and chefs, our organ of taste, the tongue, can detect only four kinds of taste!

These are the four tastes we call salty, sour, sweet and bitter. All other so-called tastes are just flavours made by combining two or more of the real tastes.

Scattered over the top surface of your tongue are more than 15,000 tiny taste buds or cells, which are connected to the brain by nerves. When your tongue comes into contact with anything you eat, the food has a chemical action on the buds and causes them to send “taste messages” to the brain.

There are four kinds of taste buds: one kind for salty flavours, one for sour flavours, one for sweetness and one for bitterness.

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This edited article about dinosaurs originally appeared in Look and Learn issue number 688 published on 22 March 1975.

Tyrannosaurus Rex attacking a Styracosaurus by William Francis Phillipps

A hungry two-legged reptile crept along the sands of the Gobi desert in Central Asia. As it snuffled in the sand, this creature, named an Oviraptor (or egg-stealer), came upon just the meal he was looking for – a nest of eggs.

The eggs were in varying stages of development and some had inside them the partly-formed young of a horned reptile called a Protoceratops.

It must have been a great find for the Oviraptor, but he did not have long to enjoy it. A violent sandstorm arose and buried the egg-stealer and his plunder.

All this is supposition. But what is fact is that millions of years later, in the 1920s, scientists found the nest, and several others. Inside them were the fossilised remains of the baby dinosaurs in various stages of growth, from newly hatched young to adults measuring 1.5  metres to over two metres. And inside the eggs were found preserved embryos.

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This edited article about life originally appeared in Look and Learn issue number 686 published on 8 March 1975.

A robot helps to save life by Wilf Hardy

What is life? Most scientists today admit that they do not know the answer to this question, although they know a great deal about the way in which plants, animals and human beings behave.

If a drop of pond water is examined through a microscope, we see things which move around and things which do not move at all. Many of us might assume that the moving things we can see are alive.

For a very long time, the words animate and inanimate were used to distinguish things that were alive from the things that were not. These words come from the Latin verb animare which means “to set into motion” or accelerate. In fact, the word animal has similar origins. Even in the times of the Romans, there was quite a natural association between life and motion.

Yet few of us today would say that things which move must be alive. Things which seem to move of their own accord, like the modern electronic robots which can fly a plane, or the guided missiles which can “home” on to their target, are not alive.

For anything to be alive, it obviously must have other properties beyond the ability to move around.

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