Neuroethology is a science responsible for studying animal behavior from the point of view of the nervous system. To do this, he uses two scientific disciplines: neurobiology, which studies the organization and structure of nerve cells and their relationship to behavior; and ethology, the branch of science that studies the behavior of animals in their natural habitat.
In this article we tell you what is neuroethology, what are its origins, as well as its most relevant scientists and major contributions to this discipline.
What is neuroethology and what does it study?
Neuroethology is one scientific discipline which studies, from an evolutionary and comparative approach, the neurophysiological mechanisms involved in animal behavior. This relatively new neuroscience focuses on the application of strategies that make it possible to determine which structures and functions of the nervous system are involved in the deployment of behaviors typical of different animal species.
As its name suggests, this discipline brings together the knowledge of neurobiology, which studies the functioning and organization of cells of the nervous system involved in behavior; I ethology, the branch of science that involves investigating how and why animals behave the way they do.
German neuroscientist Jörg-Peter Ewert, one of the pioneers of neuroethological research, believes that this science aims to try to answer relevant questions, such as what physiological mechanisms explain behavior; how this behavior develops in animals; how a given behavior promotes the adaptation of a specimen and its offspring, or what is the phylogenetic history of a given behavior.
Neuroethology specialists they use in their scientific studies animals with unique capacities that can serve as a comparative model by studying the properties of its nervous system and how it has been able to adapt throughout ontogenetic development (and at the phylogenetic level, through its species) to be able to display certain behaviors adapted to specific contexts.
Context: ethology and Tinbergen’s 4 questions
As mentioned above, neuroethology feeds on ethology, which is responsible for studying animal behavior. One of the greatest contributions to this discipline was made in the first half of the last century by the Dutch zoologist Nikolaas Tinbergen, considered one of its greatest representatives.
Tinbergen understood animal behavior as stereotypical motor models which are controlled both by internal physiological mechanisms and by certain external stimuli. According to him, each animal is endowed with a strictly limited and very complex behavioral machinery, constant across a species or a population.
The key for Tinbergen, and for ethologists in general, was to answer the question of why animals behave the way they do, and in turn to try to understand the following keys related to this question:
What is the underlying control mechanism for animal behavior?
The answer to this question would imply take into account internal (hormonal or neural) and external factors (Tactile or visual stimuli, eg.).
How is this behavior achieved in the ontogenetic development of the animal specimen?
This response would involve investigating the animal’s history, determine the possible genetic and environmental influences that favored this development.
What is the adaptive or survival value of a given behavior?
In this answer, aspects such as the evolutionary significance or the selective advantage of certain animal behaviors must be taken into account.
How has this behavior evolved over the course of the history of the animal species?
In this case, the answer would be account for the evolutionary history of the behavior in question, Analyze the evolutionary factors necessary for the appearance of behavior in the species.
Contributions of neurobiology
Neurobiology, which studies the biological mechanisms by which the nervous system regulates behavior, Is another of the scientific disciplines on which neuroethology feeds. This science owes its origin, mainly, to a series of technical and theoretical advances in the field of research on the nervous system, which also took place in the middle of the twentieth century.
In this sense, several milestones marked the development of neurobiology: the emergence of the neuron doctrine of Ramon and Cajal, the presentation of the action potential model of Hodgkin and Huxley, as well as the development of histological techniques, stimulation, recording and tracing of neural connections.
These advances made it easier for Tinbergen to call for a synthesis between ethology and neurobiology in the 1970s. give way to neuroethology, although at first it was not easy because there were great difficulties in obtaining the appropriate methods to relate the activities of individual neurons or neural tissues to the behavior of the animal in its habitat.
finally there were several scientists who led the development of neuroethology; for example, Erich von Holst, with his technique of focal brain stimulation, was able to demonstrate through various animal experiments that the stimulation of certain areas of the brain of chickens could lead to aggressive behaviors; or Karl Von Frisch, Hansjochem Autrum and Ted Bullock, who pioneered research into the neurophysiological aspects underlying the specific behavior of bees, arthropods and fish.
As we mentioned at the start, Jorg-Peter-Ewert is one of the most sought-after scientists in the field of neuroethology. One of his most relevant studies was carried out with amphibians, in particular with specimens of the common toad, with the aim of to study the neural mechanisms involved in the selective response capacity of these animals.
The German scientist studied two types of visually controlled behaviors: those of orientation or capture of prey and those of avoidance or flight. To elicit capture responses, he used visual stimuli such as long, thin, dark bars (pretending to be worms), which caused the toad to react quickly as it moved through its retinas.
By the time two sidebars were added to the stimulus (in the form of “she”) the toad’s attack response tended to inhibit – the “worm” became a “no worm”). The lymph node cells of the animal’s retina responded to objects with the appropriate speed and shape.But they were unable to distinguish between worm and non-worm stimuli.
In the study, it was found that stimulation of a structure called the optic tectum generated the behavior pattern associated with the toad’s attack response; and on the other hand, by electrical stimulation of certain parts of the thalamus, defensive flight and flight responses are elicited.
This research is just one example of what was once a pioneering study that brought great knowledge to neuroethology. Animal behavior and its neuronal correlates in many animal species are currently being studied: aggressive behavior in birds, predatory behavior in lizards or social behavior in primates.
- Ewert, JP (1987). Neuroethology of release mechanisms: capture of prey in toads. Behavioral and Brain Sciences, 10 (3), 337-368.
- Pflüger, HJ and Menzel, R. (1999). Neuroethology, its roots and its future. Journal of Comparative Physiology A, 185 (4), 389-392.