This edited article about animals originally appeared in Look and Learn issue number 623 published on 22 December 1973.

Crocodiles of the Mesozoic era

It would be a truly foolhardy character who was tempted to try holding a crocodiles mouth shut with one hand. Crocodiles are not to be fooled with. Even the zoology books fail totally to be reassuring or convincing about these creatures. True, they may state that there are twenty-three species of crocodile in the world and that most of them are comparatively harmless to man, but who wants to believe them? Confronted by any crocodile and given the choice of a zoology book or a clean pair of heels, most people will choose the latter.

It isn't difficult to see why. All crocodiles exude an air of unspeakable evil. Grinning like cruel and savage harbingers of doom, resting lazily like self-satisfied executioners, they have merely to exist to send shivers down the strongest of human spines. And the fear of them appears to be instinctive. On first seeing crocodiles, the smallest children tend to shy away nervously, as though recognising for themselves that these are no friendly playmates.

About 200 million years ago, there began the Mesozoic era, during which great reptiles dominated the Earth. Among these were the crocodilians, who turned out to be marvels of adaptability and masters of survival. When the era ended about 70 million years ago, they did not become extinct as others did but continued to hold their own in the changing world. And how well they did so is proved by the fact that they are still here today and show no signs of dying out.

All are fitted with whiplashing tails that can break a man's limb and fast-snapping jaws that cannot be prised open even with a crowbar, they are always likely to be formidable enemies. What makes them most terrifying, though, is their unpredictability.

It may be comforting, for instance, to hear that the American alligator is relatively benevolent towards man and is one of the most docile creatures known in captivity, but it in no way alters the fact that it occasionally does attack savagely. Several instances have been reported of alligators charging and overturning boats.

Of course this might mean nothing. The alligators may have mistaken the boats for amphibious creatures. Nor does the fact that human belongings – buckles, bangles and trinkets – have been found in alligators' stomachs prove that they are man-hunters. They simply may have eaten corpses floating in the water. However, that such things have happened makes most people very uneasy. That is the whole point about any crocodilians – nobody can say for certain what they will do when people are around.

If those crocodiles enjoying a good reputation can win no trust, it is hardly surprising that their extremely deadly cousins arouse extreme feelings of fear and horror. The crocodile is a cunning and savage killer. It has to be to survive.

It is in Africa that most people die in crocodiles' jaws. The most deadly is the Nile crocodile which is found from Egypt to the northern parts of Natal. It is up to 20ft long and has been feared since ancient times. Endowed with phenomenal strength, it has been known to tug rhinoceroses and buffaloes into water to drown them, so it is hardly surprising that humans present it with few problems. Exactly how many they kill each year is a matter for conjecture. There have been many far-fetched estimates on the number of people killed by this type of crocodile, but between one and three thousand is probably a fair estimate. Even if the minimum figure here is the correct one, it still represents a high toll in human life.

Sad to say, in the vast majority of fatalities, the victims themselves are to blame. They fear crocodiles, but rarely show much common sense when they are known to be around. Native women still wash their belongings at river edges and are snatched swiftly and silently by the wrists. Their tiny children are allowed to play nearby while the women are washing and never notice the crocodiles lurking in the muddy shallows. Not that this is really surprising. Crocodiles hardly stir a ripple as they sweep forward towards their prey. And the native fishermen, who above all should know better, wade unconcernedly through crocodile-infested waters or even swim in them. Apparently, when the folly of this is pointed out to them, they display a funny kind of logic. Crocodiles eat fish, they say, and as there are plenty of fish about, they won't bother with men. It is a strange kind of fatalism.

What turns a crocodile into a man-eater is hard to say. However, it has been suggested that there are more man-eating crocodiles in areas where African tribes toss their dead into rivers rather than bury them. If this is the case, it seems evident that some crocodiles acquire a taste for human flesh and become intent on satisfying it regularly.

Certainly there are crocodiles that have become exclusively maneaters. Never made entirely clear is how it can be proved conclusively that one crocodile is responsible for a number of deaths; but there are reports of especially voracious individual 'rogues.' By far the worst reported was a fifteen footer in Central Africa, said to have killed over 400 people before it was shot. Others are reported to have claimed more than 300 victims.

Throughout Africa, attitudes towards the crocodile are mixed. Some authorities offer a bounty for every one killed, and an additional bounty is paid if the contents of a crocodile's stomach prove it was a man-eater. Other authorities, however, urge its protection, and with good cause. Despised as the creature is, its end would cause infinitely more suffering than its existence. The reason for this is that a large part of the crocodile's diet consists of the barbel or catfish, which preys on other fish. If the crocodile were ever made extinct, the barbel would reign supreme in the rivers and feed on the other fish so essential to the African diet. Malnutrition and starvation would be the unhappy result.

Said to be just as dangerous as the Nile crocodile is the estuarine crocodile which ranges from the Bay of Bengal eastwards across Malaya to the Solomons, New Guinea and north Australia. Slightly larger than its African relative, it inhabits the mouths of large rivers and coastal swamps, but most surprising of all is its habit of swimming out to sea, sometimes for many hundreds of miles. No one can say for certain how many deaths it has caused, for the areas it frequents are comparatively primitive, but it is said to be a bad-tempered, unpredictable beast that strikes without provocation.

India suffers from enough man-killers as it is, so she probably counts herself fortunate that her native crocodile is no longer a serious threat to human life. Before the Second World War, the mugger or marsh crocodile used to eat possibly as many as 500 Indians yearly, but then it was hunted almost to the verge of extinction. The result was that it became a protected animal, special rangers were appointed to see that no one disturbed it in areas where it survived, and man-eating is almost nonexistent now.

In America, the alligator is considered harmless, but the American crocodile enjoys a reputation as a man-eater. Said to be the largest crocodile in the world, it often grows to lengths well over 20 feet and is found and feared mostly in Central America.

Like snakes, crocodiles are rarely loved by anyone and probably never will be.