Although once presumed to be only the preserve of a human, animals are now known to use assistance in the form of physical objects such as twigs and rocks when feeding.
By Leigh Kemp
Not only Primates
Recordings of chimpanzees using 'spears' to hunt have fascinated the scientific world for decades, however, there are many other examples of animals using tools to assist in feeding.
Rocks are the most common tools animals use in feeding with Otters crushing crustaceans whilst lying on their backs in the water and laying the rock on their bellies. Some species such as Mongoose will use a backward manoeuvring procedure to flick eggs against solid objects such as rocks to break the eggs open.
Learnt or Chance
One of the more fascinating examples of animals using tools involves the Kelp Gull, which scavenges shellfish on the beaches. When an individual finds food in the form of a shellfish it will fly a distance into the air, with the shellfish in the mouth, and drop it onto a rock or hard surface.
Most my observations of this behaviour involve a tar road as the surface to drop the shellfish on. The use of a tar road is obviously a new trait and the question arises as to how the gulls learnt that the surface was suitable to break open their prey. The behaviour of dropping hard food from a height may be an old trait but learning to use a man-made road is recently learnt. Was it by chance that the gulls learnt to use the road?
More and more examples of this tool using in animals is coming to the fore, and after years of been categorised as unusual, the behaviour is now considered a part of the evolutionary process of species.