THE NATURALIST.

Otago Witness, Issue 2607, 2 March 1904, Page 64

THE NATURALIST.

When Birds Were Snakes. — Creatures That Have Changed Their Habits.— At first sight birds and lizards seem to be about as far apart as any two races of living creatures could well be. Yet the bird family has developed directly from reptiles, and l the differences between them are far less- than those between any other two of the great families. Finding that there was a plentiful supply of food in the air in the shape of flyingi insects, certain of the smaller reptiles o£ the earth's early ages gradually developed wings, in ord'p-r to feed on it. There was thus evolved a flying lizard, the remains of which are often found' fossilised, and! which we call the pterodactyl. Its winga were bat-like, and its powers of flight not so great as those of a bird. The creatures' scales gradually turned to fe-atners, and the bird of the present age was the result. That this is no mere conjecture is definitely provedl by that very odd Brazilian' bird the touraoo, or gyp3j. The touracois about the size of a pheasant, and! outwardly lias a birdlike appearance. But on dissecting it its internal economy is found to be quite unlikte that of other birds, and to strongly resemble that of certain reptiles. Tlv* most extraordinary point about the touraco is-, however, that its young, when, first hatched 1 , have reptile-like heads, and are-, moreover, provided with claws upon their wings". They do not attempt to fly for some weeks, but crawl about on allfours, just as young reptiles do. They can use their wing-claws- for climbing up- a branch. A nestling thrown into- tno water dives at onco like a frog, and it is almost impossible to catch it. Even the grown, birds do not fly" well, and 1 altogether the touraco offers a plain proof ci the noar relationship between birds and reptiles. Young whales possess a few bristles round the mouth, a feature which belongs to no fis-h. It is only one of many proofs that whales and all their family wero at one time land creatures, and only took to the sea because they found the competition ashore too severe for them. Whales have, warm blood like ourselves, lungs for breathing air, and, instead of laying e-ggs like fish, a<ndi leaving them to chance, they tend their young as carefully as do any land animals. The tail of the whale is another point in which it absolutely differs from a fish. It is placed so as to lie flat' on the surface of the water; fish have their tails set upright or edgeways. All the oetaoea, in fact — that family which includes the whales, porpoises, andi dolphins — are merely land animals which have, for convenience- sake, taken to a marine life, and' have gradually assumed a fish-like form, according to the reeds of their new method of existence. The same may be said of all the seal and walrus family, though these, as they still spend a portion of their life on land, have not become so entirely fish-like in form as have the whales. The seals seen on the British coasts have, however, become much more fish-like than the fur seals. The latter have external ears, which the former have not; and the flippers of the native seals are much more fintike in shape than tho limbs of the fur seals. The descendants of domestic cots, abandoned on an island off the coast of South America, were found a few years later to have entirely changed their 'habits. They had not only reverted to the shape and: colour of their wild ancestors of centuries back, but had learned to like the water, and taken to a diet of fish.

Wild Animals at Sea. — A scientist has made interesting observations as to the liking of different wild animals fo- the sea. The Polar bear, he says, is the only one that takes to the sea, and' is quite nappy when aboard ship. All others violently resent a trip on water, and vociferously give vent to their feelings as long as they are able. The tiger suffers most of all. The mere sight of a ship makes him uncomfortable, and when on board he whinea piteously, his eyes water continuously, and he rubs his stomach with his terrible paws. Horses are bad sailors, sndl often perish on a sea voyage. Oxen are heroic in their attempts not to give way. Elephants do not like the sea, but are amenable to medical treatment. A good remedy in their case ie a bucketful of hot water containing 3i pints of whisky and 7oz of quinine. The Camel in South Africa.— The camel can scarcely be regarded as typical of ihe advance of civilisation*; it is, -indeed, ono of the least up-to-date quadrupeds with which we have to do in these rapidly-moving tweritieth century times. But though we may connect it with the dreamy East, where time is of no moment and "inshallah," the pious exclamation of the faithful, forms, as it were, the keynote of our progiess, tho irony of fare and the authorities of Rhodesia have lately combined to place it in a very different milieu. An experiment was made last year to introduce "Indian camels as transport animals into Rhodesia, and 34wero imported. They see,n to have borne the journey from India remarkably well, arriving in Salisbury in good condition andl without any losses, and after a fortnight's rest were put to ordinary work, carrying loads of grain and mealies between the latter town and a pkee some 40 miles off. over a road which, at all events in the. neighbourhood! of Salisbury, is distinctly trying for camels, being both hilly and rough. The male animals take, loads of 6001b -and the females of 4001b, and manage from 20 to 25 miles per day, but part of the journey is done by waggons with teams of eight camels, carrying 80001b. So far, then, under conditions which are by "no means specially favourable, these animals havo done well, and for north-western Rhodesia, as for the Kalahari, parts of Bechuanaland, and the Orange River Colony, one could not hope to find a better beast of burden. The only question is how longin such a parasite-infested part of the world, it is likely to remain free of disease. The maladies affecting horse* and cattle in Southern Africa are both numerous and fatal, and it is probable that we are still ignorant of many of them. Quite recently, for oxample, Dr Koch has discovered that the very fatal "redwaW of Rhodesia ig distinct; from the disease usually known by that name, and _is caused by a differehi; pyrosoma. But if camels can escape these and other disorders caused by the ravages of the formidable blood parasites, they are likely to play a, useful part h\ the development of the country. — Field.

— Rain falls on the eastern coast of Ireland on about 208 days in the year.