The flight of birds has been a continuous source of information and inspiration for aeronautics. Even today, studies on the behavior of birds continue to be carried out, in many cases seeking the benefits that new discoveries can bring to air navigation. Perhaps research’s obsession with profit and funding has left out other factors that may be the easiest way to explain bird behavior. Those other factors, that also include other energy efficiency components that have not been considered, are summarized in this social theory

Estonia is a transit point for numerous migratory birds. Thousands gather in the meadows to pause and regain strength before continuing their flight. It is a spectacle to go see the large flocks, majestic, an example of collaboration. And soon comes the question: Why do geese fly in a V formation?

Classic aerodynamics

The goose that is ahead, with the beating of its wings, reduces the aerodynamic resistance for those that come behind. Taking turns, they can cover greater distances than if they did it outside of a group.

But why in a V, and not in the shape of an I, a diamond, or like a bunch of cyclists?  If we consider only aerodynamic factors in the geese fly there are many ways that provide the same benefits to flying in group. They could go one after another, like cyclists in a race for example or like a car behind a truck, getting the same aerodynamic effect.

Why, if going behind has so many advantages, no goose wants to be right behind? Flying in this way reveals a big problem, and this is where I introduce the social factors. In my opinion, it is not just a factor of energy efficiency due the aerodynamic alignment.

What are social factors?

Social factors it is an elegant way of calling those factors that allow the members of a group to maintain coexistence. In this case, the determining social factor is the need to defecate during the flight. After the feeding stop is when the need to defecate in flight appears. And it is not possible to stop to defecate or hold on until the next stop, as humans do. They have to solve it mid-flight. In other flight configurations, in which one goes after the other, they would defecate on each other. To avoid this they have to fly a little above or to the side of the goose that flies ahead. And this creates a V formation.

The energy efficiency behind the social theory

The difficulty in getting funding to conduct studies on the in-flight alignment that allows geese to defecate in flight is understandable. But I think that in this case it has not been fair for the investigation of this topic to analyze only the factors related with the aerodynamics of the flight alignment, and leave aside the social factors of a group flight. I mean, there is also a component of efficiency in this theory. The important thing about this theory from my point of view is that it brings together two obvious consequences: in one hand the coexistence in a group and in the other hand the other component of energy efficiency that has not been considered in previous studies. That energy efficiency component refers to the goose’s own aerodynamic resistance: the cleanest the geese are the lowest air resistance they produce and the lightest their bodies are, so they become more efficient. Become dirty during a long journey could be a reason to weaken and perish.

Current theories seem to understand geese within study parameters that are simplified and idealized. The group of goose under study does not have changes in its aerodynamic surfaces that could alter its characteristics with respect to the ideal ones, as stated in the investigations on its aerodynamics. And this is partly so because the geese take care that it is so, that is, we do not see dirty geese because they are concerned with flying in a formation that prevents them from receiving the feces of the rest of the geese that precede them and therefore maintain their aerodynamic surface clean that is its plumage.

That is why, from my understanding, these factors should be included in the current models to obtain a more complete vision of this phenomenon.