Previously, people thought that the giraffe had such a long neck because he constantly had to stretch his neck to reach the leaves on tall trees, gradually this property was fixed in his offspring. Now we know that the transfer of traits from one generation of animals and plants to another and the change in transmitted traits — evolution — do not happen at all.
The modern model of evolution, developed in the 19th century by the followers of Charles Darwin, represents the work of evolution, which consists of two stages: the first is variability, the second is selection, that is, selection.
Volatility in evolution
Variability means that sometimes, by accident, an animal is born that differs in some ways from other individuals of this species. It may happen that such an animal has a thicker coat or its legs have a structure different from the others, which makes this individual faster-footed than others. Or vice versa, the animal may lose its ability to run fast. Volatility does not have to be good or bad. This is just an accident. Changes just happen.
Interesting fact: giraffe is the tallest animal on Earth, its growth reaches six meters. Besides the fact that he has a long neck, his tongue cannot be called short either - his length can be up to 45 centimeters.
Natural selection - simplified
Natural selection, if simplified to explain this, means the following: the better the animal is adapted to its environment, the longer it will live, and the more numerous offspring it will have.The offspring can inherit from the parent the trait that made the parent more adapted to the surrounding environment. For example, if you were a fish and your pond would take it suddenly and dry, and you could only open your mouth and turn helplessly from side to side, then you have little chance of leaving offspring, all the more numerous.
But let's say that, as a fish, you were born with unusual fins, which served as the subject of ridicule of your friends. These fins were not very suitable for swimming. But the pond has dried up, and you were surprised and delighted to find that with the help of your strange fins you can crawl with difficulty, but crawl into the neighboring surviving pond. Since you survived, then you have a chance to leave behind a brood of small fish. Most likely, they will inherit your strange, but so useful fins, they will be better adapted to life in conditions where the ponds constantly dry. A generational change is taking place, and more and more fish appear with strange fins. This is how variability and natural selection look in action.
Evolution, Long Neck and Giraffe
Such changes have occurred with the short cervical ancestors of the modern giraffe. Those animals that were born with a longer neck could easily pluck leaves from the tops of trees from the ground, which means they found more food for themselves and were more likely to survive, especially during periods when there was little food. After the change of many generations, animals with a long neck completely replaced the short-necked animals.
Interesting fact: long-necked giraffes were more likely to survive than short-necked giraffes.
The disadvantages of a long neck
Having such a long neck is not so convenient. There are many shortcomings in this. A very heavy load falls on the heart, it must do a great job to pump enough blood to supply the brain, which is so far from the natural pump that pumps blood. Animals with long necks cannot flee at the same speed as animals with a shorter neck. Even very good changes to adapt to environmental conditions also have their drawbacks.
