Three characteristics explain the amazing flexibility of crows and ravens, which multiply almost anywhere on the planet, American and Spanish biologists believe.
Unlike other species of corvids that mostly occupy only one continent, crow and crow species have a wide distribution on a planetary scale.
Biologist Joan Garcia-Porta and colleagues associated with Washington University in St. Louis. Louis, USA, has determined that the success of these birds depends on their longer wings, larger bodies and brains than their cousins.
- The long wings allow them to fly longer than other corvid species. Thus they are better scattered around the world.
- Their body size also gave them a competitive advantage over smaller species, helping them establish themselves in a new environment.
- Having a large brain gave these species an intellectual advantage over other corvids. They are able to adapt to a new environment, which increases their chances of living longer.
To establish these three characteristics associated with their success, the team examined corvid specimens from museums in Europe and the United States. The birds of the genus Corvus continue to feature longer wings, larger bodies, and larger brains than their corvid cousins.
It has been established in the past that the long wings of crows and ravens allow them to fly farther and more easily access new habitats. But the current study shows that their large bodies and large brains allow these species to survive in the new places they reach.
When we consider the ability of a species to spread, it is important to consider not only the ability to reach new areas, but also the ability to survive once there.explained Carlos Botero, professor of biology at the University of Washington in Saint-Louis.
” Our work suggests that crows and crows quickly colonize new spaces because they are particularly good at adapting to different habitats. “
Therefore, their great behavioral flexibility allowed these birds to survive the early periods of maladjustment. Subsequently, crows and crows experienced high rate of evolution of the trait. During this evolution, new species differentiate themselves from the original species, where they can no longer reproduce.
Arriving in a new environment exposes them to new selective pressures, which often promote changes in the phenotype of an organism that facilitate survival. For example, in the case of crows and crows, new beak shapes appear that are not present in any other corvid.
Details of this work were published in the journal Kind Communications (New window) (in English).
Source: Radio-Canada
