Woodpeckers (lat. Picidae) – a large family of birds, which includes 233 species.
In most cases, woodpeckers live in forests. These are climbing tree birds, which fly, although not very well. The vast majority of the family differ from other birds by an unusual chisel-shaped beak. With its help, woodpeckers chisel the bark and the core of the tree, trying to find their main food: insects and their larvae.
The woodpeckers use their strong beak not only for food but also for making nests, which are usually arranged in the hollows of trees. Woodpeckers knock on wood and communication with each other. In spring, males of many woodpeckers drum their beaks through dry trees. Such trills have probably been heard by many readers. The woodpecker’s body is almost perfectly adapted to its way of life. Thanks to this, the woodpecker can withstand significant loads, which are deadly for many other living organisms.
Wood chipping is a very energy-consuming activity. To replenish energy reserves, woodpeckers have to eat all the time. For example, a black woodpecker can eat about a thousand ants or several hundred bark beet larvae in just one “meal”. The green woodpecker eats even more – in one day it eats about two thousand ants.
The woodpeckers are called forest attendants, and this is, in principle, true. A bird, eating a large number of pest larvae of trees or adult insects, prevents an uncontrolled increase in the pest population.
Loads that a woodpecker can withstand
The average speed of woodpecker strikes is 20-25 movements per second. The total number of woodpecker blows per day is 8000-12000. For a bird to be able to withstand the overloads associated with chiseling trees, its skull and skeleton must be unusually strong. If any other bird hit a tree with such a speed, then after a few blows it would die of overloads.
Measurements show that the overloads experienced by the woodpecker reach 1000 – 1200g. This is much more than the organisms of other animals, including humans, can withstand. We are not able to withstand overloads greater than 80-100g. The highest (short-term) car overload at which a human being managed to survive is 179.8 g. Parachutists when opening a parachute experience overloads up to 10 g. Pilots who perform aerobatics are overloaded up to 12 g.
The woodpecker’s beak is strong enough to chisel a tree and not to break or deform. The tip of the beak of most woodpeckers is similar to a chisel. Thanks to this, birds can “work” with the hardest types of wood. When chiseling is active, the temperature of the brain increases. So the woodpecker can’t chisel all the time, he has to take breaks to reset the temperature.
A woodpecker has not only a strong skull and beak. This bird is equipped with a “shock absorber” in the form of cerebrospinal fluid, which suppresses the vibration. The shock absorber system of a woodpecker also includes an elastic beak, a stringy and springy hyoid bone (hyoid), and a special spongy bone in the head. A hyoid is more cartilage than bone tissue. It is located not only in the throat but also enters the nasopharynx, wrapping the skull. Thus, the bird’s skull box is one of the most advanced natural shock absorbers.
It softens the impact of more than one factor, and their whole system. During the chiseling of the tree, the beak moves perpendicular to the surface on which the woodpecker hits. If the impact is not perpendicular, but a little at an angle, the shock absorber mechanism of the bird would not work, and it could just die. But here works a well-coordinated system of muscles, which allows the head and beak to move in a straight line. When the beak hits, the muscles that pull the woodpecker’s skull away from the point of impact will immediately work.
The eyes of the bird are also protected from impact. When hitting a tree, the third eyelid (flashing eardrum) is lowered on the woodpecker’s eye. It protects the eyeball from vibration, preventing retinal detachment.
Another unique feature of the woodpecker is its long tongue. In all birds, the tongue is attached to the back of the beak. But the woodpecker’s tongue comes out of the right nostril, dividing into two halves. These two halves cover the bird’s head and neck, coming out through an opening in the beak. After that, they join together. The woodpecker’s tongue takes the insect larvae out of the deep passages made in wood.
To place within the skull all these amortization devices, the woodpecker had to do with the size of the brain. In the process of evolution, it has decreased. And the decrease in brain size did not lead to the woodpeckers becoming “stupider”. In fact, woodpeckers have a high organization of behavior. They have complex territorial and nesting habits.
But in birds, the “intellect” is the responsibility of striped calves and a layer called Hyperpallium. These parts of the brain are small in size, so the woodpecker can handle a relatively small brain.
Well, to move easily through tree trunks, woodpeckers use an X-shaped foot design. Two fingers on the woodpecker’s foot point forward and two fingers backward. Most birds of other species have three fingers facing forward and one finger facing backward. Stringent claws, strong bones of the fingers, and tendons help to hold the bark. All this provides a secure grip on the tree, and the woodpecker does not fall even during the most active “work”.