How genetics and domestication of dogs have affected the relationship with humans

One of the most interesting questions about the study of dog behavior is to understand how the process of domestication has affected genetics and how genetic differences can explain differences in behavior between dogs of different breeds.

In a new study published in Scientific reportsa group of researchers tried to find out if there were any genetic basis associated with the variability of some behaviors linked to social skills in the context ofsocial interaction with humans.

The result is that yes, depending on the selection that was made genetically and the path of coevolution with us, individuals vary their behavior and refer to human beings according to the situations in which they believe they need or not our support.

How we came to understand the behavior of the dogs involved in the study

To analyze the behavior of the dogs, the researchers recruited 624 subjects lived in a domestic environment and therefore with socialization experiences comparable to humans, belonging to 8 groups of breeds such as Japanese dogs, burrows, companion dogs, mastiffs, chicks, etc., dividing them in turn into 2 groups of different races: those belonging. to the oldest races (old group) and some more modern breeds (general group), based on their genetic distance from the wolf, their common ancestor.

They later tried theirs cognitive abilities in the context of social interaction with humans using two tests in particular, one called “test two options“And another from problem solving he called “unsolvable proof“.

The first it consisted of presenting to the dogs a wooden apparatus which had at its ends two bowls of which only one contained the food and the other was empty. After learning to associate the presence of food in one of the bowls, the dogs were tested in various conditions where the experimenters gave fewer and fewer communication signals such as through eye contact, pointing a finger until you touch them with your fingers. so that it can be tested the ability of dogs to specifically read the signs of human communication following a certain gradient of difficulty.

In the second, the dogs had to interact with a device that had at its peak a plastic container containing easily accessible food. Once the dogs had learned to associate the presence of food in that container, the latter was mechanically closed making the test “insoluble”.

At this stage, the behavior of the dogs was observed and recorded to check, due to the impossibility of opening the container, how many times they performed the so-called “look back”, That is, if they turned and looked at the experimenter, how long did they look for the eye contact and how many times they alternated this exchange of glances towards the researcher and the blocked container: behaviors that are related to ability of dogs to seek human help to solve a problem that is impossible for them.

Dogs belonging to the ancient group, consisting mainly of Japanese breeds very close phylogenetically to the wolf such as Akita, Shiba and Husky, behaved similarly to the dogs in the general group with respect to the first test thus showing a comparable ability. know how to read the communication signals of human beings. As for the second test, they sought the gaze less frequently of human beings e they kept eye contact shorter once placed before the unsolvable test with respect to the dogs in the general group.

The collection of genetic data

Along with these behavioral findings, the researchers also collected DNA samples from each dog to study the genetic differences potentially associated with the differences expressed by dogs with respect to these cognitive and social abilities tested in these two experiments.

In particular, researchers focused son polymorphism analysis (variations) of some genes already known for their importance in the emergence of biological and cognitive characteristics at the basis of different social behaviors.from the motivation to interact socially with other individuals, to the different degree of anxiety and fear in the interaction towards new environmental stimuli, etc.

They have been studied mainly the MC2R geneinvolved in the expression of adrenocorticotropic hormone receptors in the adrenal gland, therefore important in the expression of cortisola hormone that is fundamental in regulation of stress response behaviors and regulation of levels of anxiety and aggression in animals ii oxytocin genes and their receptors (OT and OTR4)the latter involved in the formation of social bonds and bonding between animals thus playing an important role in regulating, for example, the motivation of dogs to follow and seek interaction with their caregiver.

In particular, a polymorphism of the MC2R gene was associated with the success rate of the first testthat is, how many times dogs were able to follow human signals correctly, a result that is presumably due to the biological mechanisms to which this gene refers. different degrees of anxiety and fear that dogs can experience when interacting with a human experimenter in an experimental environment and that they can affect their performance in a similar task.

Gods have also been identified polymorphisms related to oxytocin genes and their receptorsit all turned out correlated with the performance results of the second testthat is, in terms of the ability of dogs to maintain eye contact, frequency and duration, all characteristics that are associated with variations in these genes precisely because they are important in the appearance of those behavioral characteristics underlying the motivation and gratification in terms of direct interaction with humansin this case conveyed by the maintenance of eye contact.

In addition, the polymorphisms of the MC2R and oxytocin genes were also found to be related differences between the group of ancient and general racesthus showing how likely the differences in behavior highlighted between these groups of dog breeds in the two tests could be explained by these genetic differences.

Taken together, these results tell us both how one exists behavioral variability that distinguishes the different actions of dogs based on their breedas much as these differences may be attributed to variations in specific genes in particular and how presumably the latter were, among others, the specific goal on which acted both the process of domestication of the dog and the process of artificial selection of the different behavioral characteristics of dog breeds.

Leave a Comment