BEHAVIORAL ADAPTATION: WHAT IT IS AND EXAMPLES - BIOLOGY - 2024

The adaptation behavior, behavioral or ethological comprises a series of features that increase the survival and reproduction of an individual, with respect to another lacking said trait.

Ethology's main objective is the study of animal behavior and understand it from an evolutionary point of view. Investigations in this body of knowledge may involve field work (direct observation of behavior) or through manipulation of the object of study in the laboratory.

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It is a branch that integrates other disciplines of biology, such as physiology, neurology, ecology, among others. This multidisciplinary trend allows not only to present a description of the observed phenomenon, but also to propose a series of explanations.

The advantage of an ethological pattern does not always depend on genetic control. In some cases, the behavior may be the result of an accidental effect, so it cannot be considered a product of natural selection.

What does it consist of?

Charles Darwin is, without a doubt, one of the most prominent figures in the world of biology. His masterpiece The Origin of Species was published in 1859 and revolutionized the field of biology, proposing the mechanism of natural selection to explain evolutionary changes.

In addition, in 1872 in his book The expression of emotions in man and animals, he shows how natural selection favors specialized behaviors for survival.

In fact, it is widely accepted by evolutionary biologists that natural selection is the only known explanation for the existence of the adaptations.

In nature we have an almost infinite number of characteristics that we classify as adaptations, from camouflage to drug resistance in viruses. The adaptations can occur at different levels, although the morphological ones are usually the most outstanding and the best known.

However, if a behavior increases the probability of survival and reproduction - in evolutionary biology the union of these two components is called fitness or biological attitude - in a given environment it can be considered as adaptive and called "ethological or behavioral adaptation".

Examples

Adaptation to temperature in ectothermic organisms

Temperature is a crucial factor in all living beings, since it directly affects all the chemical reactions that take place inside.

Depending on the way in which animals determine their body temperature, they can be classified into endotherms and ectotherms. The first group is capable of regulating its internal temperature, while ectotherms do not. In fact, most of the animals belong to the second group.

The ectothermic animals that are capable of maintaining their body temperature more or less constant and at suitable physiological ranges, would be selected and would increase their frequency in the population. This statement is correct, according to studies carried out in various ectothermic groups, particularly in reptiles.

In reptiles, adaptations to maintain the appropriate temperature consist of a series of behaviors, such as selecting environments that absorb a large amount of the spectrum of solar radiation (rocks or dark areas, for example) to reach high temperatures.

Likewise, if the optimal thermal range for the individual is low, the organism may have a behavioral adaptation to lead an active night life in order to avoid the high temperatures of the day.

Migrations

The movement of animals in search of favorable conditions or places conducive to reproduction is a behavior exhibited by a wide range of groups, from butterflies to birds and bats.

Moving to a new place brings obvious advantages to the individuals who carry out such movement, so its frequency will increase in the population.

Infanticide in a pride of lions

Infanticide is an animal behavior that can be used by males to compete with each other. In lions, for example, this phenomenon occurs.

The basic unit of these felines is the herd, made up of a group of females with close kinship relationships and their respective young. The males are not so abundant in the herd, usually there are two or three.

Males can "move" to another herd, a very laborious and traumatic task in most cases. When the new member arrives there are two possibilities: they can be violently rejected or, after an arduous fight, they win the position and become new members of the pack.

In the case of reaching the herd, the males may resort to killing the young (since they are from other parents) to gain mating opportunities. This fact favors the males but damages the reproductive success of the females.

Lionesses can cope in two ways: defending their cubs at the cost of their own lives, or spontaneously aborting when a new male arrives in the pride. This way you avoid wasting energy on playback.

Courtship in the birds of paradise

One of the greatest spectacles of nature - before the eyes of man - is the courtship dances performed by birds to attract potential mates. All energy expenditure in complex dances, display of colors and sounds has a single purpose: reproduction.

One of the most exotic cases is the typical courtship of the birds of paradise. This group of almost 40 species of flying vertebrates is very heterogeneous in terms of size, structure and color. They belong to the Paradisaeidae family and are distributed throughout Oceania and most of it in New Guinea.

Different males are in charge of exhibiting themselves to the females and they choose the one they consider "the best". The decision of the female has been extensively studied and the authors have proposed different hypotheses.

It may be that the displays displayed by the males are indicators of "good genes." Thus, females will be very selective in securing these genes to their offspring.

Another hypothesis is related to the fact of the good supplier. If the female can identify a male who is capable of providing food, parental care and other resources, she will be the one selected. The last explanation relates to pre-existing sensory biases.

References

1. Colgan, PW (1996). Perspectives in Ethology, Volume 11, Behavioral Design. Plenum Press.
2. Freeman, S., & Herron, JC (2002). Evolutionary analysis. Prentice Hall.
3. Gould, SJ, & Lewontin, RC (1979). The spandrels of San Marco and the Panglossian paradigm: a critique of the adaptationist program. Proc. R. Soc. Lond. B, 205 (1161), 581-598.
4. Hickman, CP, Roberts, LS, Larson, A., Ober, WC, & Garrison, C. (2001). Integrated principles of zoology. McGraw-Hill.
5. Immelmann, K. (2012). Introduction to ethology. Springer Science & Business Media.
6. Soler, M. (2002). Evolution: the basis of Biology. South Project.