Study in 'Science' shows that birds optimize the size of fruits consumed within the limits of their distribution areas.
Animals can adjust their diet to maximize energy consumption concerning the effort invested in searching for food. For example, birds look for fruits that fit the size of their beak, as these can be consumed more efficiently.
To understand how ecosystems function, it is common to consider that each species behaves relatively homogeneously throughout its distribution area. However, a recent study published in Science, with the collaboration of two CFE researchers (Ruben Heleno and José Miguel Costa), showed this is a dangerous simplification.
Conducting a comprehensive analysis of 831 fruit species consumed by 97 species of animals across six continents, the researchers demonstrated that, close to the limits of their range, frugivorous birds are forced to further optimize the size of the fruit consumed in relation to the size of their beak and that this pressure is less intense in the centre of their distribution area.
These results show that selective pressures are neither homogeneous nor random throughout the distribution area of each species. They are crucial for understanding how other pressures associated with global changes can condition the survival of species at the limit or even outside their ranges, historical distribution.
