The ability to use tools is not unique to humans. This behavior has also been observed in some primates and also in certain birds. For example, the crows of New Caledonia treasure small twigs that they use to extract some of their prey from their hiding places. However, it was thought that our species was the only one that had devised different techniques to crush an object for a specific purpose.
Now, a group of researchers from the universities of Saint Andrews and York, in the United Kingdom, coordinated by Megan Lambert, from the Department of Psychology of the latter institution, has found that the vasa parrots, Coracopsis vasa , have also developed this ability.
In a new study published in the journal Biology Letters , Lambert notes that these dark-plumaged birds about half a meter long, endemic to the Comoros and Madagascar archipelago, in the Indian Ocean, introduce pebbles into the shells, causing them makes it easy to grind them. At other times, they use the pebbles as if they were wedges, to crush them.
Ornithologists have long known that many birds consume bits of shells to get the calcium they need, as a supplement to their diet. Among these parrots, this behavior occurs mainly in March and until mid-April, shortly before laying.
Therefore, experts suspect that in this way they favor the correct development of the eggs. Although it is usually the males that ingest them, which at first puzzled the researchers, they often regurgitate sustenance to feed the females before copulation , so they could also benefit from the calcium ingested.
