Showing posts with label animal. Show all posts
Showing posts with label animal. Show all posts

Wednesday, September 7, 2011

The regeneration of the salamander

Imagine going to the doctor because it hurts the arm and examine it says: - Sorry, but you have to cut the arm .- to what you will answer, - nothing happens, I will grow my arm.

I will grow my arm? the doctor will probably start thinking that you're not right in the head ... but it is not just you're a fan of the animal and just read that salamanders regenerate their body parts ... and also time and again.

In nature there is quite often the regeneration of the members (the tail of the lizard or the legs of a starfish). When a body part is damaged or must shed to escape a predator just get rid of it and wait for regrowth.

The Queen of regeneration is the salamander. When one of these salamanders lost, for example, a foot, then on the stump as a small lump, called a blastema. The blastema only takes 3 weeks to become fully functional a new leg, a fairly short period if we consider that the animal can live 12 years or more. In a human, that would regenerate a limb by not more than 5 months.

Furthermore, since it takes so little to regenerate their legs, this animalete can regenerate again and again throughout his life. And to not be ugly, unattractive and unappealing to the opposite sex, the salamander not produce scars. Although I had to cut his arm several times over a long period, after 3 weeks you never notice it.

Wednesday, May 20, 2009

The Leopard seal eats persons when it is hungry, I am sure.

The Leopard seal (Hydrurga leptonyx) is the second largest species of seal in the Antarctic (after the Southern Elephant Seal), and is near the top of the Antarctic food chain. It is most common in the southern hemisphere along the coast of Antarctica and on most sub-Antarctic islands. It can live twenty-six years, possibly more.[3] Orcas are the only natural predators of leopard seals.

The leopard seal is large and muscular, with a dark grey back and light grey on its stomach. Its throat is whitish with the black spots that give the seal its common name. Females are generally slightly larger than the males on average.[4] The bulls are generally 2.5 m (8.2 ft) to 3.2 m (10.5 ft) and weigh between 200 kg (441 lb) and 453.5 kg (1,000 lb), while cows are between 2.4 meters (7.9 feet) and 3.4 meters (11.2 feet) in length and weigh between 225 kg (496 lb) and 591 kg (1,303 lb). [5]

Compared to most phocids, the Leopard seal is highly evolved for its role as keystone predator. Although it is a true seal and swims with its hind limbs, it has powerful and highly developed forelimbs similar to sea lions, giving it a similar maneuverability, a classic example of convergent evolution.
In 2003, a leopard seal dragged a snorkeling biologist underwater to her death in what was identified as the first known human fatality from a leopard seal.[7] However, numerous examples of aggressive behavior, stalking, and attacks on humans had been previously documented.[7] The leopard seal has previously shown a particular predilection for attacking the black, torpedo-shaped pontoons of rigid inflatable boats, necessitating that researchers equip their craft with special protective guards to prevent them from being punctured. The leopard seal has also been known to snap at people's feet through holes in the ice.

This seal is dangerous.

Tuesday, May 19, 2009

Tasmanian Tiger Extinction Mystery.

The Tasmanian tiger or Thylacine was by far the largest carnivorous marsupial of recent times. Its overall appearance is very canid-like. Total body length is around 1 meter. The tail length is around 50-65 cm. The tail itself is very thick close to the body and quickly tapers to a point. It is around 60 cm in height at the shoulder. The upper body is brownish/grey with a pale underside. There are 13-19 black vertical stripes that run from the mid-back to the base of the tail. The face is grey with white markings around the eyes. The fur is short and thick. Their skull has a length of 22 cm and the dental formula is: i 4/3, c 1/1, pm 3/3, m 4/4. Tasmanian tiger's long canines, shearing premolars, and grinding molars, all of which are quite similar to those of dogs. The feet are padded and leave a five-toed print. The females pouch is located by her tail and has a fold of skin covering the four mammae.
Tasmanian tigers lived only on the island of Tasmania in recent history, but fossil record shows that it was also found in New Guinea and Australia as recently as 3000 years ago. Competition with dogs brought by aborigines eliminated it in Australia and New Guinea. These dogs ran wild, becoming the dingo, which entirely filled its niche. A large population survived on Tasmania, where there are no dingoes. But when the Europeans arrived and settled in Australia and Tasmania the Tasmanian tiger was thought to be a livestock killer, especially when sheep were introduced in 1824. This was never substantiated, but because of this misconception the privet sector and the government hunted the Tasmanian tiger from 1830-1909 for bounty. In 1830, the Van Diemens Land Company, a pastoral company in Northwest Tasmania, introduces the first bounty on the Tasmanian tiger, claiming that the animal attacked sheep.

Extinction may not be forever after all; so hope the Australian scientists behind an ambitious project to clone the extinct Tasmanian tiger.
The project to bring the Tasmanian tiger back from extinction began in 1999 when Australian Museum scientists extracted DNA from an ethanol-preserved female pup in its collection.
We will see in a future if it is possible it to come back to the life, or as it has been said in several mass media, it is possible that the wolf marsupial is living , hidden from the man.Look that beautiful


Monday, May 18, 2009

The great jaguar

Jaguars are the largest of South America's big cats. They once roamed from the southern tip of that continent north to the region surrounding the U.S.-Mexico border. Today significant numbers of jaguars are found only in remote regions of South and Central America—particularly in the Amazon basin.

These beautiful and powerful beasts were prominent in ancient Native American cultures. In some traditions the Jaguar God of the Night was the formidable lord of the underworld. The name jaguar is derived from the Native American word yaguar, which means "he who kills with one leap."
Unlike many other cats, jaguars do not avoid water; in fact, they are quite good swimmers. Rivers provide prey in the form of fish, turtles, or caimans—small, alligatorlike animals. Jaguars also eat larger animals such as deer, peccaries, capybaras, and tapirs. They sometimes climb trees to prepare an ambush, killing their prey with one powerful bite.

Most jaguars are tan or orange with distinctive black spots, dubbed "rosettes" because they are shaped like roses. Some jaguars are so dark they appear to be spotless, though their markings can be seen on closer inspection.

Jaguars are still hunted for their attractive fur. Ranchers also kill them because the cats sometimes prey upon their livestock.