The Little Architect

He pays great attention to making sure everything looks perfect. He carefully places a few flowers around, along with several interesting items: straws, shells and sticks that he picked up here and there-making sure the structure he decorated and built by hand would stand out among the rest. And, he does all this just so that he can win the love of a beloved one.

Before our imaginations carry us any further- no, I am unfortunately not talking about a hopelessly romantic architect who is wholeheartedly trying to get the girl of his dreams.

I am, however, talking about a bird who does seem to act like a little architect. To be more precise, I am talking about a bowerbird (Ptilonorhynchidae), and its building of bowers as part of the sexual selection process.

A satin bowerbird set to impress with his blue-themed bower

The bowerbird family consists of 18 species, of which the male counterpart of 14 species actually build bowers or decorate clearings as part of their efforts to win a pretty bowerbird’s heart. It would be reasonable to think that bowerbirds build bowers to show their ability to build good nests for females. Interestingly enough, that is not the case. Bowers strangely look like this:

Bowers according to bowerbird species

There are 3 main variations of bowers: the avenue bower, which consists of two vertical walls of sticks on top of a broad platform based; the maypole bower, which are built around saplings or ferns; and finally, the mat bower, which consists of a mat of ferns on the forest floor (Borgia et. al, 1984).

You may now be thinking: what on earth is this little bird doing building and decorating these structures of complex variations? Well, research suggests that this courtship display further enhances the attractiveness of these male bowerbirds, and better physical displays (bower decorations) have a better chance at courtship success (Patricelli et.al, 2003) – thus the effort put into setting up bowers.

References:

Patricelli, G. L., Uy, J. A., Borgia, G. 2003. Multiple male traits interact: attractive bower decorations facilitate attractive behavioural displays in satin bowerbirds. The Royal Society, 270:2389-2395.

Borgia, G. Sexual Selection in Bowerbirds. Accessed from: http://www.clfs.umd.edu/biology/borgialab/SciAm1986.pdf

Borgia, G. Pruett-Jones, S. & Pruett-Jones, A. 1984. The Evolution of Bower-building and the Assessment of Male Quality. University of Maryland & University of California, Berkley.