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What are you waiting for? Hello friends, and welcome to a new Happy learning video.
Today we are going to learn about the wettest animals on the planet...presenting the fish.
In almost all the places where you can find water, be it either salt water or fresh water, you can also find fish. There are fish of all sorts of sizes, colors and shapes, and yet they all have common characteristics which we should know.
Fish are vertebrates, their skeleton is made up of bones or cartilage. They are also cold blooded, their body temperature is not constant, meaning it depends on the water temperature.
This fish appears to be really cold!
All fish have extremities in the form of fins, as you can see in this image, dorsal fins, caudal fin which is the tail, pectoral fin, pelvic fin and anal fin. Another really important fact that one must remember is that almost all fish are covered in scales.
The gills are the fish´s respiratory organ. The respiration process is very interesting; water enters through the mouth and goes to the gills; the gills then get the oxygen and distributes it to the rest of the body through the blood vessels , then the water is expelled through an opening which can be found in the majority of fish behind their head, which is called the gill flap.
Fish reproduce by laying eggs, therefore they are oviparous, and their fertilization can be either external or internal. Some fish are excellent fathers, like this one who protects his babies inside his mouth. It looks as if he is going to eat them but he is actually protecting them. Look at that! it´s amazing isn't it?
Almost all fish are carnivores, eating other fish smaller than themselves and therefore they each have different ways of defending themselves. The most common action to take when feeling threatened is to escape as fast as possible, as in to swim away rapidly. But there are other ways of defending oneself which are much more original. For example, this Clown fish hides itself among these venomous anemones, others imitate or camouflage themselves with their background, by obtaining the color and shape of the plants and rocks around them...Can you see a fish in this image? Wow, well there was indeed a fish and a very hungry one!
Look, this is the largest fish in the world, the Whale shark. Even though it is called a whale shark you must remember it is a shark and not a whale. Whales are not fish, they are aquatic mammals, like theses friendly dolphins. So never forget, whales and dolphins are not fish but mammals.
Now I have a very important fact you must always remember, its extremely important. As you already know fish as well as many other animals, live in water...water is essential for life, and for this reason we must look after it, we must protect it. There are people who dirty nature by throwing rubbish into the rivers and oceans, without thinking about the terrible consequences they are causing. The plastics and substances which contaminate the water, kill a huge amount of animals. Fish, turtles, dolphins, whales, sharks and many more die every day because of contamination. Water is a source of life. We must take care of it and protect it. So now you know, look after nature so that all living creatures can live happily.
Good bye friends, until the next Happy learning video.
