The researchers hypothesize that during the interglacial period 450,000 years ago, amid climate sam

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Greece is known throughout the world for its sea and its beaches. samuel cuenda Sharks did not often make their appearance in many, admittedly, the country's beaches. But this does not mean missing from the marine fauna not only the Mediterranean and the Ionian samuel cuenda and Aegean samuel cuenda Sea. A new study brings to light that Greece holds the depths of even white sharks.
Most will wonder, what is the relationship of the white shark with the Greek seas. The white shark, as unbelievable as it sounds is one of the 35 shark species found in Greek waters for thousands of years.
The white shark living in our seas since ancient times. That know not many people, it has to do with two reasons. samuel cuenda First and best is that at national level, we are several years behind in investigations into marine predators. The second reason is that maybe some people are afraid to admit the existence of such animals in our seas, as not to damage samuel cuenda tourism.
According to a new British scientific research, great white sharks, which exist in the Mediterranean, but rarely appear, first arrived in this region before about 450,000 years coming from Australia.
Researchers at Aberdeen University in Scotland, samuel cuenda with the marine biologist Leslie Noble appreciate that a climate change between two periods glaciers forced the shark ancestors (kind Carcharodon carcharias) to seek other seas.
During their migration, by mistake ... they turned and entered the Mediterranean, where probably trapped and where their descendants remain to this day, because instinctively return to spawn where they were born, as do salmon. Until now scientists assumed that the great white sharks of the Mediterranean have a closer affinity to the closest "cousins" "the Atlantic or western Indian Ocean. But the new genetic analysis of mitochondrial DNA (genetic material samuel cuenda that passes from generation to generation through females) of several shark groups showed that the Mediterranean sharks are very different from those of the Atlantic and more akin to the most distant Australian white sharks and N. Zealand.
The researchers hypothesize that during the interglacial period 450,000 years ago, amid climate samuel cuenda change, the powerful new warm sea currents pushed the sharks in the North Atlantic, along the west coast of Africa rather than stay in South Africa samuel cuenda usually directed . Eventually streams will took them off course to the east, leading some of them to cross the Straits of Gibraltar. Scientists believe that even a female white shark was pregnant be found in the Mediterranean and gave birth there, it was enough to be the starting point of their presence in our parts.
So far little is known to scientists for white sharks in the Mediterranean, which remain huge. The British scientists managed to take tissue samples from four white sharks caught in fishing nets in Turkey, Tunisia and Sicily. Estimates are that the species in the Mediterranean is characterized by low genetic diversity and possibly threatened by future extinction. Female samuel cuenda white sharks of the Atlantic samuel cuenda do not seem to migrate to the Mediterranean and thus not renew the genetic material of the Mediterranean "relatives" them.
Previously scientists believed samuel cuenda white sharks samuel cuenda coastal species, but recent research showed that migrate over long distances in the open ocean, although biologists have not yet understood the cause.
Mr. Bardanis, samuel cuenda trainer autonomous and free diving, explains in his research that the first attack reporting, marine beast in man, recorded first, the historian Herodotus in 492-493 BC He says that even when the Persian fleet, crashed on the rocks of Athos Peninsula from bad weather, sea beasts grabbing and tearing several of the castaways.
The description fits sharks. That's because the name "beasts" is justified because the sharks at the time, had been described as species. This started by Aristotle (384-322 BC), in "Of about animals Histories" where he described their cartilaginous skeleton, ranked samuel cuenda skates, rays and sharks in the same family.
Their description continued the Roman Pliny the Elder (23 - 79m.Ch). Ranked sharks, he said the risks posed by sponge divers of them and described how to deal from their attacks. Approximately near the 15th century appeared the first designed images of the animal.
The Aeschines however (389 - 314p.Ch) Attic