Hummingbird's extraordinary brain | Popular science classroom

Author:China Green Fair Time:2022.08.28

For a long time, birds are considered a type of animal with lower IQ. Their heads seem to be able to accommodate any thoughts, but the latest research reminds us that this is not the case. With an unusual brain to control its suspension, fly in any direction, and decrease rapidly.

Shooter: William Overman (William Overman)

Hummingbirds are unique in many aspects. Some of them are one of the smallest birds in the world. If they are calculated according to their body length, they are the fastest -flying birds in the world, and they are the only birds in the birds that really master the hanging. In order to obtain such special flight skills, hummingbird evolved its own unique adaptive structure.

They have 8 pairs of ribs, which are two pairs than other birds, so that hummingbirds can better maintain their body balance. Hummingbird's scapula is shorter and harder, they bear the weight of feathers. When the hummingbird hides, their wings are not fanning and down, but the entire wings remain straight and move in the shape of "8". This scapula that can flexibly rotate and complete various actions is very rare in birds.

The pectoral muscles are the power source of various techniques and movements of hummingbirds. Their pectoral muscle weight accounts for 30%of the body weight (most bird's pectoral muscles account for 15%to 18%of the body weight). This proportion also exceeds any other birds Essence Hummingbird's pectoral muscles are like a motor, and the continuous sources of power produce the wings "high frequency vibration".

An's Hummingbird (female) with honey (female)

Scientists have always suspected that this complex flight method requires a more complicated brain, but because the brain of hummingbirds is too small, research progress is extremely difficult. Therefore, it was not until recently that a scientist group in Canada managed to solve how the Hummingbird's brain handled the difficult hovering and backward flight. Their research was published in the contemporary biology magazine published in November 2016. Studies show that the brain of hummingbirds is different from any other birds (or tetra -foot vertebrates). Flying.

An of the Apodiformes of the Apodiformes, a small honeybird of the Calypte, is named CalyPte Anna. Its body length is about 10 ~ 11cm, and the male has a short and straight black bird beak; the upper body is green with metallic luster; the forehead extends to the dark rose red feathers with rainbow gloss on both sides of the face and the throat, and the lower body is gray -white dipped in dipping. Green, the feather is green under the tail, the feather is gray; Compared with the male, the cheeks on both cheeks have small gray -white spots to the back of the eyeball, and the rich red forehead and throat lack of rainbow gloss.

It is mainly distributed in North America, including the transition zone between the United States, Canada, Greenland, Bermud Islands, St. Piel and Millar Islands and North America in Mexico (As shown below: dark purple is common regions in all seasons, shallow Purple is uncommon in all seasons, dark blue is common areas in winter, and light blue is uncommon in winter).

Inhabits dense jungle, oak forests, the bottom of the canyon and evergreen broad -leaved forests, riverside forests, rare tree grasslands, coastal cities or suburbs, usually foraging 2 to 8 meters away from the ground. Pleasant natural nectar, commonly in blooming bushes or trees. At the same time, insects are also pretended to meet the protein and other nutrients they need.

To understand these differences, first of all, we must consider how we move and why. Each creature on the earth is either predators or objects of predation, depending on their position in the food chain. Therefore, for almost all animals, this means that they need to move forward, either moving towards food, or avoiding it to avoid becoming food. Humans are a rare exception in vertebrates because we have the ability to move relatively effectively in multiple directions. (Have you ever seen a puppy trying to trump or step back from the ladder?)

Despite this difference, when we face the danger, the first instinct response is still turning to escape the threat, rather than the Waltz dance movement to one side. This instinct can be traced back to the way of brain perception. Among the four -foot vertebrates of all studies, the strongest response of the brain visual center is the movement of the front and rear axis (imagine we chase someone or are chased by someone).

Hummingbird in the backward flight

Shooter: Rebecca Holmes

According to the latest research, hummingbirds are an exception. They spend a lot of time hovering around the flowers, which means that they not only need to consider how to move up and rear axis upward, but also consider moving in other directions. When they hang, a gust of gust may be blowing from their side, or a predator may launch an attack from them. Therefore, they cannot just master the way of movement in front and rear axles, but also move freely in all other directions.

Because of this, scientists find that the brain of hummingbirds is not like other animals, as much as other animals. The neurons in the animal vision system are known to the full range of visual streams (ie, Optic Flow: refers to the speed of mode motion in the image, and the detection of light flow information is essential for the direction and speed of the determination of people or animals. It has become a research hotspot for sports information processing) stimulus to show the selection of movement direction/or speed. The research team uses extracellular records to detect the bean -like nucleus (LM), which is called the bean nucleus (LM), which is called the brain of the An family and the bustygia guttata (LM). Tract, referred to as the light flow in the NOT) area, the area can respond to visual stimuli. In all the tests so far, Hummingbird has not reflected the front and rear axial motion choice preferences like other animals. On the contrary, they seem to have no preferences, and they have the same reaction to the movements in each direction. (As shown in the figure below) Figure A and C Figures are An's Hummingbird and Beltic Boys and Spasters.

(The pointed instructions instructed the direction of the movement, and the dotted line part is a pause stimulus)

B coordinate diagram (F: forward exercise; U: upward exercise; B, backward exercise; D, downward exercise), pink coils display the average excitation of the average excitation of the average stimulus of the visual stimulation of each direction (green dot) Rate, gray coil represents spontaneous neuroelectric activity (no visual stimuli)

Researchers also found that the neurons (LM: bean nucleus) in the Hummingbird's brain visual system have a stronger response to fast movement. This result is unexpected, because scientists predict that the brain of hummingbirds has an adaptive evolution of low -speed suspension, so most neurons will be adjusted to a stronger response to slow visual movements. But if you think about it carefully, it is reasonable to optimize to high -speed adaptation.

The An of Bird made a sound in order to make the tail feathers vibrate during the display. Their flight distance per second can reach 385 times that of its length, which is extremely fast (compared with, the maximum speed of a F15 eagle fighter is 2.5 Mach 2.5 Mach , That is about the distance between the length of 45 machines per second). At such a dive speed, Hummingbird will bear 10 GS (GS is the limit overload of the acceleration, fighter pilots, syncope when they bear more than 7 GS) and fly The correction of the direction, they attract female attention in this deadly high -speed dive performance, and prove their strength. If such an acceleration that is enough to make the pilot be killed, they cannot get the opportunity to mate.

Hummingbird’s brain is different from other vertebrates. This is a striking bird science discovery, but researchers have other application motivations for their new discoveries -understanding the way of flying in nature to design it to design the way of designing in nature to design it. Better robots. For example, the animal's brain can control this new discovery in three -dimensional space. It is very valuable for the design of artificial intelligence drones, or the helicopter's autonomous driving computing system. But in addition to these potential commercialization purposes, recognizing that the smallest bird brain may be the most complicated brain. Isn't this interesting?