In the human world, we often find examples of where people can exhibit multiple talents; in the sports world there can be pro dribblers, shooters and passers, in the showbiz world, skilled actors, singers and dancers. In the ornithological sphere, new studies would suggest that these multiple gifts do not exist amongst our feathered friends.
Peacocks, for example, are incredibly beautiful with iridescent green and blue plumage, but emit a shrill scream. Christopher Cooney of the University of Oxford has carried out analysis of 518 species of bird, comparing their calls to their feather colours. The focus of the study was the difference in appearance between the males and females of the species, with sexual selection determining physicality and thus the ability to better attract a mate.
Scientists concluded that there was a trade-off between good looks and a sweet singing voice with few possessing both of the gifts in question. It was found that those with fancy feathers usually have a droning or screaking single note cry.
The study revealed that if one sex of a certain species has showy plumage then vocal talents are less likely to exist. If both sexes look more similar, males tend to have a more elaborate musical range.
Why this happens is still unknown, but it may be due to the conditions that these birds live in – although the work of Cooney does not prove this. Those species that inhabit thick wooded areas, in which the visibility at ground level is poor, may have to develop a loud and characterful voices in order to find each other.
Cooney’s team favour the theory that birds only develop one key attraction trait as the evolution process is time consuming and a second trait may be of little use.
Students hoping to go to Oxbridge to study Biology or Natural Sciences (Biology) might like to explore other animals that exhibit these evolutionary traits.