The Revenge of the tyrannosaurus: why the hens are not stupid or meek

We are used to reading news that fit the expected script, as foxes slip into the chicken coops and end with dozens of chickens. For that reason, when a piece of news like the one that The Guardian published is the inverse one, it expands to the four winds.

The protagonist was a young fox, about six months old as it was deduced from the swollen pecked corpse that schoolchildren found in the morning. The animal thought that it was going away to put the boots and, with treachery and nocturnal, it slipped in a chicken coop of an agricultural school in Brittany, in the northwest of France.

The fox miscalculated his steps, probably because of the same two prejudices with which humans contemplate chickens. That is, they are stupid and meek. Little more than meat factories whose only talent, in the case of females, is to lay eggs. For most people, chickens are more foolish than other birds, such as crows and cuckoos, taken for cunning.

That is a vision reinforced by some representations of chickens and chickens in popular culture, in literature, and in cinema. Remember, for example, Heihei, the stupid cock of the movie Moana. It is a representation that could well help people feel better when they eat eggs or chicken meat produced through intensive farming practices.

There is something strange about chickens. Worldwide, they total more than 19,000 million, which makes them one of the most abundant vertebrate species on the planet. The most common bird in the world is actually intelligent and perhaps even sensitive to the well-being of its companions, which could generate some uncomfortable ethical questions for the agricultural industry.

What chickens and chickens are not fools is something that science knows thanks to a series of research published in recent years. They can count, show some level of self-awareness and even manipulate each other by somewhat Machiavellian methods. In order not to elaborate, I refer readers to a review of the scientific literature on the cognitive capacity of gallinaceae that was published in 2017 in the journal Animal Cognition.

What one concludes from the reading of that article is that according to the most recent studies, domestic chickens have been the focus of a revolution in our understanding of their psychic and social complexity. Now it is known that at least some birds are equated with many mammals in terms of the level of intelligence, emotional sophistication, and social interaction.

Hens and their bad milk

Now let’s go with aggression. It is no secret among poultry farmers that chickens can be ferocious. Flocks of free-range chickens have a clear hierarchy: the largest, strongest and most aggressive bird governs the chicken coop.

This hierarchical order implies that dominant birds abuse their power by intimidating and pecking their weakest congeners to subdue them. The birds that occupy the top of the hierarchy get better access to the watering places and the best overnight places of the ships. But these chief birds also have a special responsibility: they must watch the predators and guide the other birds to a safe place if there is the danger.

In this case, the chickens did not flee. They followed their leader and united to ambush the fox.

From caste comes to the greyhound. In poultry, aggressiveness is genetically conditioned, as demonstrated by a careful investigation by a group of Chinese scientists that was published in August 2016 in Nature.

In summary, the study found a group of genes associated with the aggressive behavior of chickens by regulating the synthesis of sortilin, a membrane protein that has important functions in neurons, and dopamine, the neurotransmitter that regulates emotions in animals. vertebrates.

Where do aggressive genes come from? Answer: phylogeny. Chickens, like all birds, are the descendants of avian dinosaurs. These, thanks to their feathers, managed to overcome the crisis of the Late Cretaceous that decimated their reptilian relatives.

130 million years ago, carnivorous avian dinosaurs like Microraptor hunted in the coniferous and pteridosperm forests of the Cretaceous. Later, the Velociraptor, popularized in the novel by Michael Crichton Jurassic Park and nicknamed “raptors” in the Spielberg homonymous film.

In the French poultry house, as soon as the sun went down and the automatic gate controlled by a photosensitive cell closed behind the fox, the birds took their personality from Lord Hyde and channeled their hidden aggressiveness of tyrannosaurs attacking the fox, which paid the duck.

Author: Manuel Peinado Lorca, University Professor. Department of Life Sciences. Franklin Institute of North American Studies, University of Alcalá

This article was originally published in The Conversation.