Questions & Answersback

Birds often fly close together. How do they manage to avoid collision?

Answer: Jon Fjeldså, Professor in Biodiversity and bird specialist has previously responded to this same question – he writes: In general birds have amazingly fast reactions. When birds flee, they coordinate their movements among themselves, as you often witness in flocks of several thousands of birds.
They can almost turn on a sixpence and this is because they are immediately able to understand each other’s signals. Sparrows and swifts in particular have a large brain that instantly perceives movement.
And in the case of swifts, the muscle around the neck vertebra is specially designed so as to allow lighting fast movements of the head.
They use this ability when hunting for insects but also to keep a close eye on what is going on around them.
They have muscles down their neck with very long fibres, which also suggests a specialisation towards very fast movements. We see the same thing when the great tit flies into thickets.
It never collides with a branch. The reason for this is lightning fast manoeuvrability.
In small birds the distance between the sensory organs and the brain is shorter than humans. In old people in particular it takes longer for the brain’s nerve impulses to reach the limbs.
This slight delay does not exist in small birds such as the great tit. And they do not use GPS or radar, as in the case of the bat.
In addition the birds rely on hereditary instincts and learned rules to establish how they move in relation to one another within the flock. In a flock of wild geese, for example, the individual birds exploit the air current from the bird in front of it so their wing strokes are always coordinated.

My own opinion is: It is hard to generalise but in the animal world there is a tendency that the smaller the animal, the faster its ability to react. This is why the birds do not collide.
We also know that the physiological processes that occur when the brain sends out a nerve impulse take place much faster in animals with a high body temperature, as is the case of birds.
The normal body temperature of a small bird is approx. 44° C. If a human being had such a high temperature it would die of fever.