This edited article about animals originally appeared in Look and Learn issue number 249 published on 22 October 1966.

The bittern among reeds as the moon rises

‘Attack is the best form of defence’. If animals knew this, it would make a lot of difference. Small birds often fare badly at the paws of a cat, but sometimes a courageous bird, because it has eggs or young, will fly at a cat, calling vigorously, and may end by causing the cat to beat a hasty retreat.

The American mockingbird, a member of the thrush family, has been known to attack crows, hawks, snakes and cats which have ventured too close to its nest. An American woman reported seeing a cat approach close to a tree in which mockingbirds were nesting. Suddenly a bird plunged from its perch and dived at the cat, striking it behind the ears. It did this again and again, returning to a different perch each time and thus carrying on its dive-bombing tactics from various angles. The cat fled in terror. The bird returned triumphantly to its nest.

Many birds depend upon flying to get away from their enemies. However, there are some birds that do not fly, notably the ostrich which has only small wings, incapable of lifting its huge body. When an ostrich fears attack it will lower its head and push its tail up, remaining absolutely motionless so as to merge with the surrounding bushes and trees. If the attacker advances the ostrich relies on its powerful legs to carry it at great speed over the ground. Each leg has two toes, one bigger that the other and bearing a large claw. This is a formidable weapon when an ostrich lashes out at an enemy with its strong legs.

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This edited article about marine animals originally appeared in Look and Learn issue number 248 published on 15 October 1966.

Scorpion Fish

Probably the commonest animals in the sea, after fishes, are those known as molluscs. The name itself is from the Latin and means ‘soft-bodied’.

The great majority of molluscs have this soft body enclosed in a shell as a protection. In some, the shell is in two parts and hinged; these are known as bivalves. Others have a spiral shell; these are the univalves, and are often called sea snails.

Not only does the shell of the sea snail protect the body of the animal that makes it, but when the mollusc itself dies, a hermit crab may make use of it. Unlike the more familiar crabs, only the front part of the body, as well as the claws and legs, of a hermit crab are armoured. The abdomen is soft, and to protect this the hermit crab takes over the shell of a dead sea snail and uses it as a ‘house’. It can do this without difficulty, because the hermit’s abdomen is twisted in a spiral that fits easily into the spiral of the shell.

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This edited article about animals originally appeared in Look and Learn issue number 247 published on 8 October 1966.

Giant armadillo

No animal is without enemies. Some have few, others have many, but all must be ready to defend themselves. They do this by one of two methods. They use either active defence, using whatever weapons they possess, or by passive defence, by some form of armour, or by deterring an enemy without ever striking a blow.

A dog or a wolf uses active defence when it flies at and bites its opponent. Its only weapons are its teeth, especially the long canine teeth, or fangs. But even these animals will avoid a fight if possible and try, in the first place, to put off an enemy by scaring it. If this is ignored they raise their hackles, bare their teeth and crouch ready for the spring. Their ears are laid back, out of harms way, the face is twisted into a scowl and the growl turns to a snarl. Only if these signals are ignored do they attack.

Although a skunk’s method of defence is very different, there is the same kind of warning. A skunk first stamps its feet, then it raises its tail and waves the tip up and down. These are signals to an enemy to go away before the skunk squirts a most obnoxious fluid from two glands under its tail. This fluid can be squirted a distance of 12 feet, can burn the skin or hair and can cause blindness if it goes into the eyes. Its odour last a long time and may spread over a radius of half-a-mile.

The skunk advertises its unpleasant qualities by its prominent white markings, and this has been called a warning coloration. Most poisonous or stinging animals carry a warning coloration. Usually the colours are black-and-yellow, black-and-red, all black or all red. The wasp is a familiar insect that is coloured black-and-yellow. Its defence is active: it stings. But several insects have a passive defence based on this, they are coloured black-and-yellow, and look like wasps. A young bird catches a wasp in its beak, is stung and thereafter leaves all wasps alone, as well as any insects that resemble them. Such insects are said to mimic wasps: and we speak of this as protective mimicry.

Perhaps the best forms of passive defence are seen in the armadillo and the tortoise. In both, the body is enclosed in a bony armour covered with horny plates. The tortoise’s shell is more like a fortress into which the animal withdraws. The armadillo has a flexible suit of armour. The hedgehog achieves the same end by carrying a coat of spines and rolling into a spiky ball when attacked.

Some caterpillars have coloured spots on their bodies that look like eyes. As long as the caterpillar is crawling normally, a bird may get ready to eat it. But if it draws in its head, thus expanding the ‘eyes’, the bird is scared and flies away.

This edited article about humming birds originally appeared in Look and Learn issue number 246 published on 1 October 1966.

Ruby-throated humming birds

Like an iridescent ‘will-o’-the-wisp’, the tiniest of the humming bird family, comparable in size to a bumble bee, hovers on wings beating so rapidly that the human eye sees only a coloured blur. It is the high frequency wingbeats that cause the humming sound to which they owe their name.

The Bee humming bird is only two inches long, half of which is bill and tail, and yet its wings beat 50 times per second as it pauses before a flower. Its slender beak is inserted into the corolla of the flower, and the long, very flexible tongue, shaped rather like a double tube, is extended to reach the nectar at the bottom.

Humming birds eat fruit juices, and any insects or spiders they find on the flowers, as well as nectar.

Their flying habits are really extraordinary, consisting of a series of rapid darts, varied by hovering and curious tumbling evolutions. They fly faster than any other birds and they can even fly backwards at speed. Their swift, darting flight enables them to catch insects on the wing, like their ancestral relations, the swifts.

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This edited article about animals originally appeared in Look and Learn issue number 244 published on 17 September 1966.

Harvest or Field mouse's nest by R B Davis

Many animals make nests, either for resting or to lay eggs or give birth to young. Birds build nests only for laying their eggs. They sleep elsewhere, either perched in trees or on buildings, or squatting on the ground.

We do not usually associate the furred animals, or mammals, with making nests, yet most of them do, usually as sleeping quarters. Gorillas, for example, select a place in a tree and bend the smaller leafy branches in towards it to make a sleeping platform. They make a fresh nest each night.

Rodents, such as rats and mice, as well as squirrels, are particularly given to making nests. Squirrels make elaborate nests of twigs, known as dreys. These they line, usually with leaves. The pack rat of North America makes a house of twigs with four compartments and connecting passages.

It is interesting how the mammals transport their nesting material. A badger gathers bracken or grass and drags it over the ground, moving backwards. It is a laborious task, and the noise made as the bracken is dragged along can be plainly heard. Usually quite a lot is spilt along the way, especially when grasses are used. What with the track a badger wears in the ground as it walks to and fro, and the pieces of grass littering the track, it is easy to follow this nest-builder.

A grey squirrel is more skilful. You can sometimes watch it collecting dead leaves. It will pick up a leaf in its mouth, run over to another, lay the first leaf neatly on the second, then pick up both. By repeating this, it will finally have a bunch of half a dozen leaves in its mouth. Then it will run to a tree, climb rapidly up the trunk, disappear inside its drey and, a few seconds later, reappear empty-mouthed.

Apart from apes and monkeys, which use their hands, and badgers, which use their paws, there are remarkably few mammals that employ anything but their mouths for nest-building. Even small rodents, like the harvest mouse, which build woven nests of grass, do not use their paws as ‘hands’. To weave the walls of their nests, they thread the grass by pushing it through with the snout and pulling out the other side with their teeth.

The outstanding exception is found in some of the Australian animals. These, as everybody knows, are unlike the furred animals in other parts of the world. They are mainly pouched animals (marsupials), in which the females have a pouch on the abdomen for carrying their babies. The marsupials include kangaroos, wallabies and opossums. Because they have this pouch, they do not need a nest for their young, but many of the smaller marsupials make a nest for sleeping in, and they transport the materials needed to build it by wrapping the tail round a bundle of grass or leaves.

One opossum, known as the lesser-flying phalanger, which is two feet long, including its foot-long tail, spends its days sleeping in a hollow in a tree. At night it comes out to feed on blossoms. To reach these it launches itself into the air and glides from tree to tree, using a fold of skin on each flank as a parachute, and the tail as a balancer.

When building its nest, however, it climbs along a branch, hanging by its feet like a sloth. It picks off leaves for its nest with its teeth while hanging by its hind feet. It passes these with its front paws to its tail, which it wraps round them. Eventually the phalanger climbs back into its nest in the hollow tree, holding a bundle of leaves with its tail.

This edited article about whales originally appeared in Look and Learn issue number 242 published on 3 September 1966.

The Whale family

For centuries the great whales of the world’s oceans have been hunted for their oil and meat. It is only in recent years that whalers have realised there may one day be a scarcity of these mammals unless some form of protection is given to them.

Generally whales are regarded by people as a form of large fish that live in the sea. Apart from that, very little trouble is taken to learn more about them.

In fact, they are varied and fascinating animals which can be found all over the world, in Arctic, Antarctic, tropical, sub-tropical and temperate seas. Some members of the whale family even live up rivers in fresh water.

Whales are all true mammals, and so are much more closely related to dogs and cats than to fishes. They have lungs and breathe air just as animals and humans do, but instead of the usual nostrils, they have a hole on top of their head known as a ‘blow-hole’. This blow-hole has a valve which closes when the animal dives under the water (this is called ‘sounding’). The valve stops any water going down into the lungs.

Old pictures of whales show them blowing huge spouts of water from the tops of their heads, but after investigation this was found to be just a little water and warm air. The air inside the whale’s lungs reaches body temperature, then, when the used air is forced out through the blow-hole, it cools rapidly on reaching the air outside and becomes steam. A little water may be trapped in the blow-hole, so that from a distance the mixture looks like a small water-fountain.

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This edited article about the Soldier Crab originally appeared in Look and Learn issue number 240 published on 20 August 1966.

Various crabs

The Oriental Soldier Crab lives, as its name suggests, in the Far East, on the shores of tropical countries. Every time the tide goes out, numerous crabs can be seen coming out of their burrows to scuttle about over the muddy sand on their long, thin legs, pausing every now and then to feed. To some people they look like armies on the march, and this is why they are called soldier crabs. However, if anything frightens them, they rush helter-skelter across the sand, like a panic-stricken army in disorderly retreat.

As the tide goes out, it leaves behind, on the surface of the sand, tiny plants and animals called plankton, so small that they cannot be seen with the naked eye. It is upon these that the soldier crabs feed. On their claws the crabs have delicate, rather spoon-like fingers. With these they scrape up the surface sand, and push it into a slit between the maxillipeds, which is the name scientists have given to the two small plates at the front of the crab’s shell.

Somehow, behind the maxillipeds, by means of tiny vibrations, the food is separated from the sand. The food goes into the crab’s mouth, but the sand, and anything else the crab cannot eat, comes out of the slit as a small round pellet, which the crab brushes away with one of its claws. It then scrapes up more sand and the process starts again. As these crabs are very common in the Far East and it is usual to see hundreds of them running about at low tide, it is not long before the shore is covered with the little pellets of sand.

A very close relative of the Oriental Soldier Crab, does not scatter pellets all over the place when it feeds, but instead makes a tidy cluster of them near the entrance of its burrow. Some soldier crabs even arrange the pellets in patterns, in straight rows radiating out from the mouth of each burrow.

The Oriental Soldier Crab breathes air all the time, and therefore it must take a supply of air into its burrow when the tide comes in. As soon as the tide begins to flow, each crab makes a small hollow in the almost liquid sand. Then it turns on to its side, and runs around backwards pushing little lumps of sand upwards and outwards with its feet. This makes a circular wall. Gradually, as the crab adds more sand, the wall increases in height and the top arches inwards to form a dome, like an eskimo’s igloo. Finally, all that is left is a small hole in the top.

This the crab plugs with one last lump of sand and the igloo is finished. The crab is now safe from danger, whether from hungry fishes or the pounding of the waves.

If the crab wants to go deeper into the sand, it just digs downwards, pushing the sand up to the top of the dome of its igloo. As it does this, the air trapped inside the igloo sinks with the crab so that it can breathe easily no matter how deep it goes.

As soon as the tide goes out, the crabs come out of their burrows and start feeding again. How they tell when the tide is ebbing, no one really knows, for the crabs, in their igloos, cannot see what is happening. One suggestion is that there is less pressure inside the igloo as the water recedes, but there may be a completely different way in which the crab is kept informed about what is happening overhead. One may be that the crabs, like so many other animals, have an ‘internal clock’ geared to the tides.

This edited article about parrots originally appeared in Look and Learn issue number 237 published on 30 July 1966.

Sulphur-crested cockatoo

From as far back in history as we can go, primitive tribes have kept parrots as pets. The Ancient Greeks and Romans kept parrots, and when English seamen went out to the Spanish Main to harass ships from West Africa to the West Indies, a parrot became almost as great a prize to bring back as a pocketful of doubloons.

Parrots are related to pigeons on the one hand, and to cuckoos on the other. Yet they are unlike both of these in appearance. And they are so unlike all other birds that nobody has any difficulty in telling a parrot when he sees one. All have large heads, short necks, two toes in front and two behind, and they all have strong, hooked beaks.

As might be expected, because they are scattered all round the globe, the members of this family are known by many different names, such as parrots, cockatoos, parakeets, macaws, lovebirds, parrotlets and budgerigars, as well as many others. It would take too long to tell how one kind differs from another, there are more than 300 species, but in general, all parrots are brightly coloured, easily tamed, and can learn to talk. The range of sizes is large. Some, like the pygmy parrots of Papua, are no bigger than a sparrow, while the gaudy macaws of South America may be over three feet long. A good way to identify two of the more usual kinds is that cockatoos have erectile crests and parakeets usually have long, pointed tails.

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This edited article about insects originally appeared in Look and Learn issue number 234 published on 9 July 1966.

Huge dragonfly-like insects lived in prehistoric forests

Two questions which will probably occur to anybody who looks at insects in all their variety are: “Why are there so many of them?” and “Where did they come from?”

Study of the lives of insects gives us an idea as to why there should be so many, for every different sort does a particular job which is not done by anything else in the area in which it lives. The large numbers of different species can be accounted for by the limited abilities of each one, for there are few “Jack-of-all-trades” among insects.

To discover how insects came into being is much more difficult, for in the animal kingdom are many related creatures. Spiders and crabs, for example, both have jointed legs attached to a hard skeleton outside the body. But these are cousins, not ancestors, to the insects.

We know what the ancestors may have looked like, however, through the discovery of a “living fossil” type of animal, known from many tropical parts of the world. This is called Peripatus, or Velvet Worm, because its body is covered by a huge number of tiny bumps which look like plush.

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This edited article about the dragonfly originally appeared in Look and Learn issue number 233 published on 2 July 1966.

Various types of dragonfly

One of the largest insects in Britain today is the dragonfly. Today’s dragonflies are, however, mere dwarfs compared to some kinds which lived in the past and grew to a wingspan of as much as 30 inches.

Nonetheless, modern dragonflies are in many ways like their ancient ancestors in both shape and way of life. For example the larva, or the “nymph” as it is usually called, still does not go through a resting or pupal stage before changing to the adult state.

Another curious thing about dragonflies is that, although they all have four wings, these are not used as two pairs together, as in more recently evolved insects, but as separate pairs.

Although some of the big species can fly faster than most other insects, they beat their wings rather slowly – about 14 times per second. The rustling noise made as they fly is caused by the wings brushing against each other.

At one time, their size and the noise of their flight made people fear dragonflies. An old country name for them is “Horse-stingers”, but in fact they never attack any creature which they cannot catch in flight and carry away.

At the edge of a stream or pool in summer the small dragonfly-like insects called damsel-flies can sometimes be seen. Usually these have a rather weak flight, and when at rest they are able to fold their wings over their backs.

Dragonflies’ wings are not “hinged” in this way, but are held stiffly at the sides at all times.

Dragonflies and damsel-flies start their life in water, where they hatch from eggs usually laid on water plants. The nymph is not the beautiful creature that might be expected from its name, but a dull brown insect. They breathe through gills, which are internal in the dragonfly but look like three little fan-shaped tails in the damsel-fly.

These creatures should not be put into aquariums with small fishes or tadpoles, for they are fierce hunters and will eat any small animal or insect they can catch. They do so by lurking in water weed until some small creature comes close enough, and then shooting out their mouthparts, which work rather like a moveable arm or “lazy tongs” to grab and hold their prey. After the meal, the mouthparts are folded back against the head again.

The nymph stage may last for two or more years in some dragonflies, but finally, when the insect is fully grown, it climbs out of the water on to a waterside plant and sheds its skin for the last time. What emerges is the adult dragonfly. At first the wings are crumpled, but they dry and harden within an hour.

Most dragonflies are rather pale-coloured at first, but darken later. They often leave the water for the first part of their adult life, to spend some days or weeks feeding on insects. When they are ready to breed, they return to the water.

An adult dragonfly hunts by sight. Its antennae are tiny and its sense of smell poor, but its eyes are huge, and it can see very well. It is particularly good at detecting movement. It will fly after other insects, which it grabs and holds with its hairy legs, to eat them in flight.

A dragonfly can often be seen flying up and down a regular “beat” over the water. This is its territory, which it will defend against others of the same kind.

Damsel-flies have much the same sort of behaviour and, as their territories are very much smaller, they are easier to watch. Many damsel-flies have a sort of warning behaviour, for if another damsel-fly approaches one which is at rest in its territory, the owner of the area will raise its body as if for flight. As the body is usually brightly coloured, often with contrasting bands near the tip, a damsel-fly of the same species will be warned that the area belongs to somebody else. If it does not fly away, it will be driven off by the owner.

One of another species will usually be left alone by the territory holder, for the two species have slightly different needs, and will be able to fit in together in the same area. If the sun should go in, the dragonflies and damsel-flies will all stop flying and go to roost in waterside plants.

Although the dragonflies are large and strong predators, only a few of their eggs survive to maturity. The reason is that they have many enemies, which include water beetles, newts, fishes and birds.