What animals of egg bear?Somehow, teaching zoology at school, I asked pupils: and in what animals differ from the same birds and reptiles? Not everyone remembered the second name of a class of animals - mammals therefore among answers two more appeared. The first: animals are hairy. The second: animals are viviparous. The fact that animals can lay eggs fairly surprised many.
From the Russian folklore:
A have you ever seen anything like it
I in what village slykhano, That the chicken of a bull-calf gave rise to
the Pig a small egg demolished
Yes on a regiment carried away...
Representatives of a subclass yaytsekladushchy (or in Latin Prothotheria - pervozver) - the duck-bill and the echidna - nowadays live in Australia and its vicinities. What is unsurprising - this isolated continent was always a shelter of various relic creations.
A. Marshall “I am able to jump through pools“:
“Duck-bills usually departured up the river and then, without turning, provided to a current to carry itself back, and were engaged in searches of worms and larvae in water at this time. Sometimes, when they floated by, we took them for fishes as on a surface of the river only their curved backs were visible, and threw a rod in their direction. If the duck-bill swallowed a bait, we pulled out him on the coast, ironed, said about how it would be desirable to retain it, and then released back in water“.
“The duck-bill is not an animal, and a profession in hospital“.
In due time yaytsekladushchy brought a lot of headache to naturalists. When in 1798 the skin of a duck-bill for the first time got to Europe, scientists considered it as a foolish joke. Such mystifications when taxidermists “sewed“ from parts of different animal mythical basilisks and a mantikor, were quite widespread in those days. Therefore scientists can be understood. And that you thought if showed you a small animal with a tail of the beaver, a beak of a duck and sharp-clawed webby paws covered with brown fur?
It that else for jokes: there is no
the Tail of a beaver, and a nose from a duck,
I either a duck, or a beaver?
S. Aksyonenko “Falling of the empire of Inca“:
“Scientists have to doubt everything. And to accept only those hypotheses about which the last doubts disappear. Let the truth will triumph a bit later, but the lie will not triumph. Yes! there were sometimes also misunderstanding capable today to raise a smile. For example, scientists did not believe in existence of a duck-bill.... Also left so that any inhabitant trusting in a duck-bill in that CONCRETE case was more right, than scientists. But the inhabitant both in a chimera, and bald believed in the devil if only he entertainingly about it was told. Therefore once with a duck-bill, than thousands of times with chimeras is better to be mistaken. Especially as soon scientists thoroughly studied these duck-bills“.
it is valid, in a year of a duck-bill recognized as the present and even found at it mammary glands. Zoologists as the new mammal gave them the next surprise did not manage to calm down: in 1884 in the face of the naturalist V. Caldwell the female of a duck-bill was delivered of egg! Everything was necessary to reconsider again.
Process of childbirth at a duck-bill happens so. The female not just gets into a hole (where duck-bills and live), but also immures an entrance to it the earth. - a crypt and temperature is maintained in such maternity hospital, and predators do not disturb. The female takes down 1 - 3 eggs and like a brood hen warms their heat bodies until utkonosik hatch. Further, as well as it is necessary at mammals, feeding begins milk. However, a mlekopitaniye at a duck-bill quite primitive. Mammary glands are not united in uniform system and remind stalemate. The duck-bill has no nipples. Therefore to feed cubs, the female turns over on a back, and milk gathers on a stomach cavity from where kids just drink up it.
F. Krivin: “All mammals passed
from eggs to milk long ago, but spouses Utkonosy preferred that and another. And they laid eggs, and brought up cubs milk (and suddenly there will be neither milk, nor eggs?) “.
the Relative of a duck-bill - the echidna - externally is not similar to it at all, but too is very fancy.
Entry in the logbook of the captain Bligh 07. 02. 1792.:
“The lieutenant Gyosri, walking on the coast, killed an animal of very unusual form. The small head so imperceptibly passes into a trunk that it is hardly possible to tell that the animal has a neck. Instead of a mouth at it an utinoobrazny beak of two inches with an opening on the end... A tail small (but not such, as at penguins), covered sharp, as at a porcupine, needles of one inch“.
If the beak of a duck-bill (very sensitive, it is necessary to tell) serves for the same for what and a duck (to filter water in search of food), then the long beak of the echidna is necessary to put it in ant hills and termitaries. Strong termitaries, the echidna destroys previously by powerful claws, and pinches insects a long tongue with horn cloves on the end (they pound food).
Which - that our heroine adopted at... kangaroo. Specifically - a bag on a belly where the echidna places the eggs. In the same place she bears and hatched - absolutely bald - cubs until at those needles do not begin to grow.
Ability to lay eggs - not the only thing that unites the echidna and a duck-bill. From ancestors - reptiles - they had also foul place - the termination of a back gut where also channels uric and gonads open. Besides, as well as at reptiles, the body temperature of yaytsekladushchy is changeable and capable to vary within 4 - 14 degrees.
is an animal quite harmless,
However, an exterior at it unenviable. People the poor thing called
People, think again! As to you it is not a shame to
When the Russian scientists named the echidna (so in Russia usually called a venomous snake), they meant her unusual frightening look. However it became clear that yaytsekladushchy virulence is really not alien. On hinder legs the duck-bill and the echidna have peculiar spurs. The prick of such spur will cause only unpleasant long pain in the person, and here the dog can easily die.
But usually the echidna is protected absolutely in other ways. At first it tries to be earthed quickly, having left outside only needles and if there are no time and opportunities for this purpose, it begins to be turned by a ball, like a hedgehog.
By the way, despite the small sizes (about 30 - 45 cm) it is malicious - quite strong small animal. The case when the echidna locked for the night in the house moved all furniture there is known.
And here larger (65 cm) a duck-bill - an animal very impressionable. It is capable to die of only one nervous shock easily. For this reason of the first live duck-bill it was succeeded to bring from Australia to Europe only in 1922.
Exist one more kind of yaytsekladushchy - so-called, the pro-echidnas living on the island New Guinea. From just echidnas (inhabitants of Australia and Tasmania) they are distinguished by larger sizes (to 77 cm), longer muzzle and higher paws. Also on each side the heads of the pro-echidna it is possible to see small external ears, and needles on her back are located more accurately (as though they were slightly brushed).