Why can't ostriches fly?
Ostrich: Ostriches are the largest surviving birds in the world, they can grow up to 3 meters and run at speeds of up to 70 kilometers per hour. Ostriches can reach a maximum height of 2.5 meters when running, and a distance of 8 meters in one step.
Most birds have a pair of strong wings that can fly freely in control. However, there is a kind of bird that has wings but cannot fly, and this is the ostrich.
In fact, once upon a time, ostriches were able to fly. Later, due to changes in the earth's climate, ostriches began to live on land. As ostriches adapt to land life, their wings begin to degenerate, becoming short and small, and their feathers change to become unfit for flight. At the same time, the ostrich's body became very tall, and its legs became strong and powerful. Although ostriches lost their ability to fly during evolution, their ability to run on land was enhanced, making them more suitable for land life.
Why do elephants have long noses?
Elephants: Asian elephants generally have a shoulder height of 2.3 to 2.5 meters and a weight of 4 to 8 tons; African elephants have a shoulder height of 3.2 to 4.2 meters and a weight of 5 to 10 tons. An elephant's nose can roll up huge objects weighing 1 ton, or it can pick up something as small as a peanut
Elephants appeared on Earth a long time ago. At that time, elephants had short noses and small bodies. In the fierce competition for survival at the time, the elephant's diminutive body made it easy to be eliminated.
In order to win the competition, the elephant had to change itself and let itself grow tall and grow. However, when the elephant's body becomes tall, there is a problem with their feeding: if they want to eat the grass on the ground, the tall body needs to lie on the ground, which is very inconvenient. In order to be able to easily eat food, elephants learn to roll up the grass on the ground or the leaves on the trees with their noses. Over the course of a long evolutionary process, elephants have retained this habit, and their noses have gradually become very long because of this habit.
Why do dogs like to spit out their tongues and gasp for breath in the summer?
Dogs: Humans began domesticating dogs about 15,000 years ago, and dogs were the first animals to be domesticated by humans. Dogs' eyes can distinguish very few colors, and the world in their eyes is only black and white.
In the summer, the temperature rises and the heat is overwhelming. When the weather gets hotter, we'll notice that the family dog often spits out his tongue and gasps for breath quickly. Why?
It turns out that the dog's sweat glands are all on the tongue, and in the summer, if the dog feels hot, they will spit out their tongue to dissipate the heat. If the dog feels that it is still hot, it will speed up its breathing speed. When the dog gasps for breath quickly, it will inhale a lot of cold air, and when this cold air passes through the nose, it will take the heat out of the dog's body so that the dog will not feel hot.