How ants find their way home has been studied and continues to be studied by thousands of scientists. And not just like that: this ability of insects involves many mechanisms that allow you to take a fresh look not only at the world of insects, but also at the abilities of man himself.
As it turned out, ants find their way home in several ways at once. They use for this:
- orientation to the sun, although most people themselves by the sun are unlikely to be able to orient themselves in space
- memorization of landscapes and various objects
- chemical methods
- built-in pedometer
- Earth's magnetic field.
And, as myrmecologists (scientists who study ants) cautiously note, they fully admit the existence of other mechanisms that allow ants to accurately find their way home, but have not yet been studied by man. Although each of the above methods is very effective in itself and can provide ants with error-free navigation.
On a note
Scientists call the craving for their place of residence or birth the word "homing" (from the English. Home - house). It is especially pronounced in salmon, which unmistakably find the river in which they hatched as fry from caviar, after many years of living in the ocean expanses.
Chemical labels on routes
All ants, without exception, use the chemical method of orientation.They are generally characterized by high sensitivity to odors and a tendency to chemical communication. Ants do not make sounds, and in some species, working individuals are completely blind, and smells remain the only way for them to communicate, search for food and navigate in space.
For communication and formation of labels, ants use various pheromones specific for each species and for each specific situation. Including - and for marking routes.
It is interesting
Smells are also used by many slave ants and insects that parasitize in anthills. For example, having learned to produce pheromones characteristic of a particular species of ants, they penetrate their dwellings and there either feed on ant stocks or their eggs, or kidnap larvae, or simply live in conditions that are comfortable for them.
To return to the anthill, each ant leaves microscopic scent marks as it moves. And the paths along which insects move especially often look to them like highways to humans. And "trodden" once - like a path in the forest.
The topochemical sense in ants is also very important, thanks to which they can determine not only the smell of the mark, but also its size and direction. Even dogs do not have such a subtlety of smell: a hunting dog, having stumbled upon the trail of a hare, can make a mistake in the direction of the prey. An ant, having met a chemical label, will know exactly where the previous and subsequent labels are located, as well as in which direction the anthill lies, and in which direction the food source lies.
You should not consider this ability of ants as drawing peculiar arrows with pheromones.This is a visual interpretation of such a phenomenon, but it works on the same principle: in the amount of an odorous substance and its smell for an insect, all the necessary information is encoded.
On a note
In order to confuse the ants, it is enough to “kill” the smell of their road mark with a stronger aroma. Simply spraying the trails with deodorant is sufficient for this. However, thanks to the innate diligence, the ants will very quickly restore the original path.
Thus, each ant trail is a kind of road with a large number of direction indicators that are understandable to each working individual.
Physical objects as reliable landmarks
Remembering the location of various objects and elements of the landscape, which is so understandable to us, is also characteristic of ants. However, given the size of the insects themselves, this way of orienting them has some peculiarities.
- Ants remember objects of their scale: grass bushes, individual stones, cracks in the ground. It would be too reckless to expect them to navigate buildings and rivers.
- The ant actively supplements the system of original pictures of the territory with navigation through the celestial bodies. In laboratory experiments, it was found that if the feeding area of ants with an anthill is rotated relative to the Sun, without changing the position of landmarks, the insects become confused. Of course, such situations do not happen in nature, which makes such a system very reliable: if the landscape around the anthill is seriously changed (for example, grass is cleared), the insects will still orient themselves according to the Sun.
Interestingly, some ants actively train their mates to find their way home and find food. Moreover, such training is not at all like simply following one forager (a member of the anthill specializing in obtaining food) after another: if the “student” lags behind the “teacher”, the teacher waits for him and helps him find the best path.
Sun Orientation
The ability of ants to navigate by the Sun is very complex and is still being actively studied.
First, ants can take into account the direction to the Sun even during short and small movements.
Secondly, these insects are able to correct for the displacement of the luminary over time. Even if the ant runs away from the anthill in the morning, and returns only by noon, he will take into account that during this time the Sun has risen above the horizon.
Thirdly, in the eyes of ants there are special cells that take into account the direction of sunlight. So they do not have to do any calculations: their brain itself receives information from the target cells and makes the necessary correction.
Landmark - Earth's magnetic field
It is still not completely known whether all ants use orientation by the Earth's magnetic field, or only leaf-cutting ants studied specifically for this purpose. But as a result of the experiment, it turned out that in case of violation of odor marks and in the absence of sunlight, the behavior of ants could be changed by introducing certain interference into the magnetic field in the area of insect movement.
Most likely, some of the ant's organs work in compass mode, catching the direction to the north, which, when combined with other orientation systems, helps the insects find the direction they need to move.With its help, ants find their way home even at dusk, when the Sun is already hiding behind the horizon.
Ants find a home... counting steps!
And this discovery in the field of ant behavior turned out to be the biggest surprise for ethologists: many species of ants count the number of steps taken in a certain direction to find food. Today, scientists even believe that ants count steps between each turn.
This ability was discovered by a research group that conducted an unethical experiment: several ants from the same anthill had their legs trimmed, and several more had miniature stilts glued to their legs. The group of "short-legged" ants ended their way to the food before reaching it, while the group of "ants on stilts" successfully ran through the area with food and began to look for food further, where it was not.
In most ant species, when searching for a way home and in general when orienting in space, if not all of the above, then several of the described methods are combined, which increases the accuracy of finding the desired route. For many ants, this is especially important. For example, representatives of species living in deserts risk simply burning out in the sun or dying from dehydration on the surface of the earth with a temperature of about 50 ° C if they fail to return to a cool hole at the right time.
It is possible that ants in the future will give people a few more surprises in the field of orientation in space.
Interesting video: an example of how ants drag rich prey home
Ants are terrible.