In a recently published trial, researchers suggest that human activities may create new phenotypic behavior / physiology couplings in wild animals.
Human beings have clearly become a force independent of nature. Whether it be, where human activities are clearly implicated in the acceleration of the latter, or in the phenotypic evolution of the fauna that surrounds us. In appeared in the review Public Library of Science Biology, researchers suggest creating new categories of within wild animals to reflect some empirical evidence. To help us better understand this essay, we interviewed Philippe Huneman, CNRS research director in philosophy of biology and medicine at the Institute of History and Philosophy of Science and Technology at Paris-Sorbonne University. .
Behavioral syndrome: proactive versus reagent
Until now, it was generally consideredas a continuum from proactive to . Proactive individuals show boldness, aggressiveness and activity more important than their reactive counterparts who are more timid, less aggressive and more passive in the face of stressful stimuli. These behavioral phenotypes are correlated with physiological variables. Reactive individuals have more marked responses at the hypothalamic-pituitary and adrenal axis and lower activity of the compared to proactive individuals. But this essay we are talking about turns things upside down. ” This kind of model is rarely engraved in the , specifies Philippe Huneman. The philosopher develops: At first glance, the theoretical distinction is very strong, but in the face of new data, it is obvious that this type of rather simplistic model must be revised. “
Human beings disrupt the natural environment …
By its activities, the human being, while being subjected to the laws which govern nature, participates in modifying it. For example, the, which is a very ancient practice, protects prey from their natural predators and facilitates access to food for domestic animals. But, for several decades, many other things have changed and participate in reshaping the phenotypic traits of wild animals, . These activities bring humans into close contact with various species and their populations of proactive and reactive individuals. These individuals maintain relationships between themselves (we speak of an intraspecific relationship) and between members of different species (we speak of an interspecific relationship).
… and creates new couplings between behavior and physiology
By disrupting the architecture of the environment and crucial parameters such as access to food or protection, we would participate in creating two new couplings between behavior and physiology that researchers have called pre-preactive individuals and preactive individuals. The former would be present in environments where the human shield is weak, such as weakly urbanized places or ecotourism places far from cities. Under these conditions, reactive individuals become more daring as their physiological response to theremains the same. Conversely, proactive individuals see and their audacity diminish. The latter would be present in environments where the human shield is strong, such as in very touristic places and city centers. Under these conditions, reactive individuals become more daring, their physiological response to stress decreases while their cognitive capacities and their aggressiveness remain the same. Conversely, proactive individuals become less aggressive, their physiological response to stress decreases, their daring remains the same and their cognitive abilities improve.
How to explain these changes?
Philippe Huneman informs us that there are three hypotheses. “The first hypothesis is ecological in nature. A process of colonization has taken place, a niche, that is to say a specific type of space where thecan exist, opened up and animals that already possessed the right traits came. The second hypothesis is behavioral in nature. Indeed, a phenomenon of phenotypic could explain these empirical observations. The third hypothesis is evolutionary in nature, i.e. there is a change in , which, by definition, is not the case in the case of phenotypic plasticity. Here the induced by humans and their activities may have progressively favored the reproduction of preactive or pre-active animals to the detriment of others. The test remains descriptive and does not decide between these hypotheses. Also, they are not mutually exclusive and hypothesis number 2 frequently precedes the occurrence of hypothesis number 3. ”
If you have noticed, what is amazing is not so much the changes, but the fact that human activities seem to have the ability to decouple behavioral and physiological traits in wild animals. ” What this trial suggests is that human activities induce new couplings between behavioral variables and physiological variables. Moreover, it is enough to walk in some cities to realize it via our simple senses, for example when approaching pigeons ”, details Philippe Huneman. But would there be only the human being to generate such phenomena? Maybe not. As Philippe Huneman tells us, “It is likely that other forms of commensalisms produce similar effects. For example,». Nevertheless, in terms of the magnitude of the consequences, the human being seems to be unique in its kind, as for the .
The importance of relationships between individuals of the same species
During our interview with Philippe Huneman, an interesting subject emerged during the conversation: the fact that. « For a very long time, this discipline remained in an interspecific paradigm, being concerned mainly with interactions between species. With this model and these new data, we realize the ecological importance of intraspecific variations, which are usually the prerogative of evolutionary disciplines. All this renews the question, which had never received a consensual answer: “What if two niches of species intersect?” “, asks the researcher.
What should be done ?
With all this information in our possession, a question arises: what should be done? This is the same question we collectively had to answer when we realized the tremendous impact of our human activities on the climate. It also arises for the design of areas of human activity. ” Do we want to move towards a world where the difference between wild and domestic animals is blurring? raises Philippe Huneman. The researcher develops: In short, do we want to reduce the opposition between human nature and non-human nature? Do we want to continue on this path and, ultimately,? Or is it considered that there must be purely wild spaces where animals and plants would not be exposed to humans because, if they are, as we have seen, they will eventually change? ? These are two readings that are debated in the literature on the subject. One wishes to preserve the wild, the other to bring lasting peace to the relationship between humans and animals. But at what cost ? “, concludes the philosopher.