Three-eyed Lizards of New Zealand

Among sun-baked rocks on barren islands off the New Zealand coast basks a solitary survivor of the days before the dinosaurs. It is earth’s oldest back-boned inhabitant, a fugitive in time from nature’s harsh law of the survival of the fittest—the tuatera, or three-eyed lizard. Its big, dreamy hazel eyes have watched the procession of the ages for 300,000,000 years—the beginning and extinction of the dinosaurs to whom it stood in about the relationship of a great uncle, the coming of birds and mammals, milleniums of famine and milleniums of plenty, the shattering and crashing together of continents. It has survived while all its contemporaries of the earth’s ancient days have died, largely because it has been willing placidly to watch the parade pass without bothering to take any part in the tumult and shouting.

The feature of great interest about the tuatera, both popularly and scientifically, is its third eye. This third, or pineal, eye is closer to its original form in the tuatera than in any other living creature. Just after the little reptile is hatched the organ appears as a dark spot under a film of thin, semi-transparent skin. In a baby tuatera it becomes a small knob on top of the head. Thick, opaque skin covers the eye in the adult reptile and it is difficult to distinguish. Anatomists doubt whether the animal actually sees with the pineal eye any more. The fact remains that this organ can be distinguished easily and that it retains, in degenerated form, the characteristics of a seeing eye which has nerve connections with the visual cortex at the back of the brain. Moreover, when the third eye of an infant tuatera is dissected there is clear evidence that it once was a double organ.

The tuatera is about two feet long from its snout to the tip of a crocodile-like tail. It has a scaly skin with a row of spines along its back. Its large hazel eyes are its most conspicuous feature. They have a soft, dreamy expression, and they never appear to blink. There are no external ears, but the sense of hearing is highly developed. One way of drawing the creature from its burrow is to play a tune on almost any instrument.

It does not dig its own holes under the rocks. Usually it shares the burrow of a black-and-white petrel—known in New Zealand as the mutton-bird—and it remains there even when the bird incubates its eggs and feeds its nestlings. Apparently a mutually satisfactory arrangement has been reached between petrel and lizard. The former usually are in their nests only at night. The tuatera spends most of the night away from home, hunting for the insects which are its favorite food. Occasionally, it has been observed, a host will become tired of his persistent house guest and try to evict it. In such a case the tuatera never puts up a fight. It leaves placidly and tries to find some other petrel with whom it can share quarters. If this search fails it will, as a last extremity, scoop out its own burrow, although apparently such labor is against its deeply fixed principles of making no effort which possibly can be avoided.

The lizard goes to sleep about the middle of April, the beginning of winter in New Zealand, and wakes late in August, when spring is well underway. Then for seven months it grows fat on insects.

The creature is reportedly capable of living for 500 years and more. It shares its longevity with its distant relatives, the great turtles. Its long life, during most of which it continues to breed, doubtless has been a major factor in its racial survival.

The ancient reptiles were plentiful when white men first came to New Zealand early in the last century. The Maoris regarded them with superstitious awe and avoided them as much as possible. But early British settlers and their dogs used to kill the inoffensive creatures for sport. This was the first active enmity the tuateras ever had known. They saved themselves by withdrawing to the barren islands and becoming even more seclusive in their ways of life. Thus they clung to a thin thread of existence until an enlightened government threw the protection of the law around them.

Today the three-eyed lizard is probably the world’s most rigidly protected animal. The New Zealand government has placed all sorts of legal restrictions on hunting or capturing it, and to kill one would be a major crime. For that matter, very few persons living ever have seen a tuatera. It stays in seclusion most of the time. There is a single specimen in the zoological park at Wellington. When a party from a Byrd Antarctic expedition visited there they were told that the lizard had not been seen for several months and that it was highly improbable that it could be lured out of hiding. One day it would appear of its own volition, take a philosophical look at the twentieth century, eat a few flies, and retire to its lair under some rocks again. Here probably is the secret of the race’s longevity. The little lizard has spent most of its time sleeping. It has existed with the minimum of effort. It has been satisfied with its lot and, above all, it never has gotten in the way. It has been observed, for example, that one of the creatures never climbs over even the smallest obstacle. It always will walk around.