Wednesday, June 27, 2012

The lamprey, the vampire ocean.

If we made a list of the strangest animals in the world, the Lamprey would be among the first places. It is known as the vampire from the depths.

It's a prehistoric animal that has not changed for 500 million years. When evolution had not invented the mandible as we know it today. It is a euryhaline organism. This means that animals are able to live in a wide range of salt concentrations without altering its metabolism. And so are found in rivers, lakes and seas. In fact, the Lamprey was born in a river, and return to spawn as salmon do.

But nothing Lamprey resemblance to a salmon. The lamprey is parasitic, not predatory, also thanks to its suction mouth is able to cling to the stone to help up the torrents of the rivers. In fact, they are so different that taxonomically speaking not considered fish, being so peculiar, have their own group, the paraphyletic group of cyclostomes.

But go to the outlandish. The mouth of the Lamprey, mouth-suction cup that reminds an alien movie, devoid of jaw. This has the shape of a funnel trimmed teeth and tongue corneal scraping. Attaches to the skin of its host and once hooked up to suck and suck, there has been the case, to kill her.

When the lamprey is a larva, feeds on a different form, has no teeth that we see in adults, nor have eyes. They feed by hairs (called barbules) that filter food. When adults go to sea, living as deep as 500 meters. They reach weights of 1 kg and 1 meter in length (40 inch), then return to spawn in the river, which left between 50,000 and 200,000 eggs ... Those are a lot of eggs ... Then lampreys die as do salmon.

It is very common in the North Atlantic and the Mediterranean Sea, where this animal is conceived as a tasty snack and a part as an essential ingredient in recipes in culinary traditions as old as the Roman.

Thursday, June 21, 2012

The sperm whale.

The king of seas, oceans a top predator can defeat a group of Orcas (killer whales), descending to great depths and hunt giant squid. The sperm whale (Physeter macrocephalus) is undoubtedly the animal with greater ability to kill (this sounds a little nerdy) in the world.

But it is true, can weigh almost 50 tons, is the largest toothed mammal, and has very special characteristics. For example:

The sperm whale can be lowered to depths of 3,000 meters, holding their breath for more than 1 hour and resist the high pressure that occurs at these depths. When your heart beats dives 1 time per minute, and lungs contract to handle the pressure. Pressures we are talking about 30 million Pascals ... it is like having to put up at the tip of the little finger, 5 bulls on top of each other, and that in each cm2 of the skin of the whale. In addition, blood has a dense, with many red blood cells and this reduces nitrogen production, something that all divers are afraid and so are decompression.
All these physical adaptations allow the mammal to become deeper dives.
Another thing that stands out is the sonar. Sunlight begins to disappear at a certain depth (about 400m I think), the abyssal darkness prevails and vision, the eyes, is useless in these places. But the sperm whale has devised how to move easily and even hunt prey as elusive as the giant squid. The crack produced by the sperm whale is the loudest sound produced by any animal, but its function is unknown (although it is believed that sonar and used as a weapon to stun their prey).
The sperm whale can get to be more than 20 meters and, as we said, 50 tons and has a serrated jaw 5 meters. It is a mammal, lives in family groups, and has no predators. Still, is in danger of extinction ... for now in a vulnerable state.

Tuesday, June 12, 2012

Aequorea victoria.

If we plunge the water in the ocean and we began to fall and fall until the light disappeared, and the pressure, dead silence and total darkness, we suddenly discover that there is a world of amazing animals, strange and fascinating. An example of these animals, may be the jellyfish Aequorea victoria or crystal jelly.

A bioluminescent jellyfish in the light of day is almost invisible, but in the darkness of the deep produces a beautiful light, a light which hypnotizes and traps prey in his wonderful tentacles filled nematocysts (cells that inject toxins).

Not long ago it was discovered (2009), yet little is known of it. If I am not mistaken is the only animal that produces green light, thanks to a green fluorescent protein (GFP, for its acronym in English, green fluorescent protein), produced only by the jellyfish Aequorea victoria.

It inhabits the west coast of North America, but as often happens lately with many jellyfish, the number of specimens of this species is growing due to the disappearance of predators.