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Freediving

Freediving is an extreme sport and it's about suspension of breathing voluntarily.
This sport is the opposite of all sports because in the freediving isn't about physical training. It is about relaxation of all organs and muscles for don't spend so much oxygen, and this is more difficult. Freedivers before doing freediving they do relaxation exercises.
Freedrivers wear ballast to not float so much and this way they can stay motionless in the water. This ballast can change depending on the depth and the weight of this person.

The other trouble is pressure. How do they go down 50 to 100 m?
They have two ways:
1-The traditional way:
Everybody knows this way, we put the fingers on the nose and put pressure, when you feel ears hurting you kick off the air from the nose. But this way in the long run is harmful for your ears. Also this way you can not go down so far.
2-Frenzel:
This is the way all the professionals freedivers use and has three parts:
Step1- Mouth fill
Step 2- Close your throat 
Step 3-  Use tongue as piston
If you do well you can feel air going to your ears.

But this sport has many risks, the most important risk is the syncope.:
It's like fainting. The  syncope comes from of scarcity of oxygen in the brain.
If you have a syncope you can lose one of the senses. One professional had a syncope and he lost the taste sense for one year.

Records:
Go down without flippers ---- 101 m
Go down with flippers --- 128 m
Go down without flippers (dynamics apnea) --- 226 m
Go down with flippers (dynamics apnea) ---- 281 m
Static apnea --- 22 min


When I was little my dream was to fly and when  I am alone and in complete silence, floating in the marine bottom it's like flying. This is why my favourite sport is freediving.

 

Type of whales

The whales are the most surprising  creatures of the world and they live in all the seas of the world. Which are mammal, a long time ago they live in the land but now are completely adapt to the sea, like a dolphins. Also they can breath with his horn. The horn is in the upper part of his head.
The scientists think that whales and hippopotamus come from the same species but they progressed with differents ways.

There are two big group:
- The whales with beard:
They are the majority whales, which have sieve in the mouth for filter the foodstuff.
- The toothed whales:
They has fang, with witch use for hunt.

We can distinguish for his diet and his physicals features.
Also we can classify with the number of his nostril.

The whales are pursue and hunted  for the humans for two reasons:
- In some areas they hunt whales like a sport very popular because of its size.
- In other areas they hunt the whales for pet foodstuff and supplies.
These are also the main reasons why whales are an endangered animal. Nowadays the population is 5.000-12.000 whales in the world, but 300 years before the population was 239.000.



Blue whale:
It is a  whale with a beard and  it can live in almost oceans.
This whale can reach 30 m long and 160 tonne weight.
Its main power soure is krill and cepepods.

Humpback whale:

It has big pectoral fins and can live in most oceans.
The female whales are bigger than male whales.
Its main food source are small fish and krill.

The fear hunter of the ocean it's now the prey

Scientists are bewildered because they find dead great sharks in different parts of the world.
Which animal is bright and big enough for killing a great white shark?

Eli Martinez, an expert in sharks, has done different experiments to find out the answer to this question.

Eli has a  theory: another more evolved than sharks, has found out the shark's weak spot.
This weak spot is the tonic immobility.


Tonic immobility is a defence  mechanism usual by many animals. In the event of shark, perhaps that turns on when the shark is face up, that makes the shark susceptible.
But this isn't the only way to make the shark susceptible, also we can do when we stroke in the lower part o f the snout.

Now I explain the experiment which Eli did to confirm this theory:
First, he does the test with a silky shark (one of the fastest marine animals of the world, but also it's a small shark).  First he catches the shark by his tail and after spins it.

                              First                          











                                 Second







Now he tests with whitetip reef shark. This time he puts on chainmail doublet to protect himself from the bites of the sharks and he checks the other way for make the tonic immobility in sharks.

                                 First


       

                             Second






He checks his theory with small sharks, now he will checks with great sharks. But now he takes off the chainmail doublet to improve mobility.

First he confirms the theory with the tiger shark:


With this shark he has problems because when he strokes in the lower part o f the snout, the shark attempts to bite  him. But bit by bit he accomplished.






Finally he checks the theory with the Great White Shark:

But the shark attacks him and he decides to go into the cage.

When the sharks attack Eli he accomplished to caress his snout for one second.

That make the shark groggy. He thinks if he can do that more time, he will get the same result with others sharks.






Now only he has to find the responsible. This is why he goes to the place where appear 100 deads sharks. After analyzing the ambient he decides to see a recorder where they record the scene.
In all of them appear the fin of the killer whale.
For this we can say: killers whales learn to find the weak spot of sharks and they use this to eat.