Monday, May 21, 2012

Echidnas or spiny ansteater. Evolutionary experiment.




This animal is called echidna or spiny ansteater, and has a characteristic that is shared only by another animal, the platypus. Like this, the echidna is the only mammal born from an egg ... I find it strange?
I explain briefly:

The earliest forms of childbearing occurred in prehistoric ocean water. The fish gave birth to many small fish of the sea and of those, many were devoured. To avoid this, the evolution devised some different formulations of childbearing: some fish were hidden in the mouth of the mother, others sought shelter in ... for example anemones ... and other small fish were kept in capsules viscous. The last way to protect the lineage separated was evolved over time in typical eggs of reptiles.

The capsules were no longer viscous but tough. Eggs that were getting the fetus evolve and grow into predators, hunters and adults, but with a smaller size. When mammals appeared, how to give birth to offspring changed. The egg was fertilized in the mother and, even without having the capabilities of an adult, was birthed. Of course had to be cared for and fed by the mother, trying to ensure that offspring born (usually) helpless.


Well, in this evolutionary path of procreation, which seems normal that any mammal born from the mother and then her nursing care and to become more, not an egg as birds or reptiles. That is because the echidna evolutionary peculiarity: the echidna is born from an egg, therefore, how they procreate is not like reptiles but not like that of mammals.

But the way to incubate the egg is not such as birds or reptiles. The echidna lays an egg and it's in a cavity of the body to the coat. This allows you to navigate and provide warmth and protection while ... a good idea talking about survival. Then yes, the small born and would do what any mammal: nursing.

Thursday, May 3, 2012

Musk deer.





If we see skull of this animal, one can think that belongs to a predator of large tusks. Remember the saber-toothed tiger. But really it isn´t a carnivorous hunter, not a key animal in the trachea fangs of its prey, does not infringe fatal bites. This skull is that of a peaceful vegetarian: musk deer.

  In contrast to other deer, the stags antlers do not grow, but two huge tusks that give it the appearance of deer-vampire (a term invented by me). Well, these tusks grow throughout his life and apparently, its function is the same as that of other deer antlers ... size does matter.

Another feature of the musk deer is that unlike other deer, he lives as a couple.

There are several species and they think they are smarter than other musk deer do not.

Finally, perhaps the most significant trait. We note that the name given to this deer is due to their body scent of musk. A strong sweet smell, which contains pheromones and is used in some perfumes. In fact, there is a very nice story about this feature:


When the deer began to feed himself, he noticed the strong scent of musk. He wondered, perplexed, where he came fresh and enveloping perfume.

Began to investigate its source everywhere, it was impossible to escape him, but so was to know its origin. The animal became more and more curious. No truce, was still looking for the source of the smell so intense. He sought constantly, day and night, the victim of an obsession that did nothing but increase. So the years passed. Hart lived moments of great weakness, of unspeakable anguish, deep grief. did not get your search results.


Fifteenth century engraving


Musk deer aged and died. "I never knew that intoxicating perfume came from himself."


This musk-containing glands in the snout. But there is also another ingredient that it produces and which also becomes a target for hunters. It is through the flesh, not by the need to eat. It is hunted by a glandular substance is used as "drug" for athletes. Is prohibited and is considered doping.

Thanks to its smell, its doping substance, in fewer habitat (if I have not said is just east of Asia), its conservation is threatened.