The giraffe is big, it’s more difficult for him: how to provide brain nutrition at six meters height

The giraffe is the highest of all land animals that inhabit the planet. Males of this species reach 6 meters, females are slightly smaller. Of course, this is convenient in the savannah, where the most juicy and green leaves grow on the tops of trees. But just think about how much effort you need to make to the body in order to function normally in such difficult circumstances.

Giraffe, or rather 6 of its subspecies, lives only in Africa. Despite their apparent clumsiness, giraffes run excellently and in case of danger can reach speeds of up to 50 km / h. According to scientists, the long neck of giraffes has formed as an adaptation to the dry conditions of the savannah and a limited amount of food. Due to such a high position of the head and a flexible neck, giraffes may not compete with other herbivores. Giants of the savannah always have enough food, because only they have access to the upper tier of trees.

Scientists have always been interested in how the giraffe’s heart provides oxygen and nutrients to the animal’s brain, which is so far and high. To clarify this, several theories have been put forward and even experimental models built. As a result, biologists managed to unravel the secret of the giraffe.

In order to provide nutrition to the brain, located at a considerable distance from other organs, nature awarded the giraffe a truly unique cardiovascular system. It turns out that he has a very powerful heart, which weighs up to 10-12 kg and is capable of pumping 60 liters of blood per minute. In this case, the pressure that is created by the heart of a giraffe to supply the brain is three times higher than in humans.

A powerful heart manages to supply the brain, but what happens when a giraffe leans in? How is the differential pressure compensated, and why does the giraffe not suffer from dizziness? But even here wise nature found a way out. The giraffe has special locking valves that block the large cervical vein, thereby blocking the movement of blood in case the head is lowered.

In addition, the giraffe has another interesting evolutionary acquisition. His brain is surrounded by a special network of reserve vessels. If a giraffe tilts its head, then surging blood fills these vessels. And when the animal raises its head, the blood vessels slowly give out blood, preventing the oxygen starvation of the brain, which could occur in the event of a sharp outflow of blood.