Animals typically have a wide range of behaviors to chose from, however some behaviors are predetermined by genetics. Researchers from the University of Sheffield have used genome sequencing to identify the genes that determine male striking mating behavior in wading birds known as ruffs.
The mating system for males of this species works by the males gathering together and investing a high amount of energy into attracting females. There are 3 distinct breeding behaviors in this system. Territorial breeding males have plumes around their necks called ruffs. The coloring in these males varies greatly to make them distinguishable. Nonterritorial males have white feathers and concentrate on stealing mates from the territorial males. The 'cross-dresser' males mimics females. This makes it easy for them to hide amongst the territorial males and steal mates.
A study published in Nature Genetics shows the three distinct breeding behaviors are encoded by a "supergene", a section of chromosome that contains a hundred or more genes. This supergene was created several million years ago by a chromosomal rearrangement.
What makes this supergene special is that it allows a lot of genes that are next to each other which determine multiple traits such as hormones, feathering, color and size. The combination determines the mating patterns for these male birds. This study shows that personality and behaviors are not always up to us but can be predetermined by our genes.
Article used: http://www.sciencedaily.com/releases/2015/11/151116112456.htm
Related article: http://www.uu.se/en/media/news/article/?id=5612&area=2,5,10,15,16&typ=artikel&lang=en