Keeping one’s distance is a natural mechanism for avoiding infection, researchers clarify. Using examples, they show how widespread the various forms of social distancing are in animals and what parallels and differences there are to human behavior. Lessons can be drawn from this for how we deal with the risk of infection, say the scientists.
The Corona crisis is forcing us to behave that many people find new and unnatural: Various rules and measures are intended to create more distance in order to limit the transmission rates in society and to reduce the personal risk of infection. In a certain way, however, we orientate ourselves towards nature or reinforce our own intuitive reactions, according to the overview study by the research team led by Sebastian Stockmaier from the University of Texas at Austin.
The scientists first illustrate this with the passive form of social distancing. As they explain, this is a side effect of infections that many people are sure to know from their own experience: If we feel bad and listless due to an illness, we prefer to stay in bed than meet friends and thus automatically ensure increased levels Distance. As a striking example of this passive form of social distancing in the animal kingdom, they highlight the behavior of vampire bats: evaluations of distance meters on the back of experimental animals have shown that sick individuals of these socially living animals withdraw and spend significantly less time in the vicinity of conspecifics spend. It also became apparent how beneficial this reduction in social contacts is to the spread of infections among the animals.
With a human perspective, co-author Dana Hawley of Virginia Tech, Blacksburg says, “Staying at home and limiting interaction with others is an intuitive behavioral response when we feel sick – and one we do in many species can watch. However, people often suppress this instinct to withdraw, for example because of the pressure to keep performing or out of a sense of duty. This can cause great harm to ourselves and our communities, ”said Hawley.
Look at the forms of keeping your distance
As she and her colleagues further report, there is also an active form of self-isolation: sick people behave accordingly when they consciously stay away from others so as not to infect them. A parallel to this is known from ants: In some species, sick individuals deliberately leave the community. The researchers regard these reactions as a selfless service for the common good: Active self-isolation protects the rest of the colony from infection. In the case of bees, on the other hand, an example is documented for the case in which the healthy individuals purposefully ensure distance from the sick in order to protect the community. Certain signs allow the insects to recognize certain diseases in their hive mates and then react quite brutally: the infected are excluded from the community.
In other species, however, it is the healthy individuals who leave the group to protect themselves from disease, the researchers report. An example of this can be found in the case of Caribbean lobsters: in order to avoid the risk of catching a virus, the animals leave their group as soon as they perceive that a member is infected. Apparently this behavior outweighs the disadvantages that are also connected with this reaction – because the lobsters lose the protection of the group. But this risk is apparently lower than the risk posed by the virus. Parallels to the corona pandemic are also obvious in this case: As a rule, the costs and advantages of social distancing are opposed to one another.
Intuitive avoidance behavior
Similar to humans, many animals instinctively distance themselves when they perceive signs of a possibly contagious disease in a conspecific, reports the team. This has been documented in the case of guppies, for example: the fish avoid conspecifics who show clear signs of infection. Probably each of us has shown similar behavior at some point. “We have some behaviors to minimize our risk of disease that we show without thinking because it’s evolutionarily anchored in us,” said Hawley.
“For example, if we’re on a plane and someone is coughing next to us, we’re more likely to avoid a conversation or lean noticeably to the side to keep some distance,” says Hawley.
Similarly, mandrills also avoid contact with group members who appear ill, the researchers report. However, these socially living primates appear to be strategic about their social distancing behavior in a manner similar to ours: they tend to sometimes increase their risk of infection by continuing to care for infected close relatives. At least we enjoy some advantages, the researchers conclude: In contrast to animals, we can use communication technologies that can create at least some social connections and bridges while maintaining a safe physical distance.
Source: Virginia Tech, Technical Article: Science, doi: 10.1126 / science.abc8881