Genes responsible for the three kinds of male ruff identified
By Diane Mar-Nicolle
Simon Fraser University biologist Dov Lank and a team of researchers have identified the genes responsible for three different kinds of male ruff (Philomachus pugnax)—a species of wading bird.
The ruff is the only bird species in which three kinds of males exist, each having its own approach to courtship and mating and with distinct physical characteristics. One is a fighter, the second is a “wingman” and the third is a cross-dresser.
In a paper published today in Nature Genetics, researchers found that 3.8 million years ago an inversion occurred in the chromosomes of the ruff, creating a second kind of male. Then 0.5 million years ago, a second chromosomal rearrangement between the inversion and the original sequence occurred, creating a third kind of male.
As a result, there are three types of male ruffs: one with ancestral sequences, another with an older kind of the inversion and a third with a newer kind of inversion.
Lank and his wife Connie Smith of SFU’s Centre for Wildlife have been searching for the genetic component that leads to differences in the behavior and plumages of male ruffs for 30 years.
His past studies demonstrated that, contrary to most complex characteristics in most species, the differences in behaviour and morphology among male ruffs were strictly governed by differences in their genes rather than environmental factors.
“Today we have the tools to identify exactly what genes are involved, and over the next few years we will describe how they work,” says Lank, who presides over the world’s largest ruff aviary, located on SFU’s Burnaby campus.
“These genes control differences in aggressive behavior and the expression of gender-specific traits, and the pathways and processes involved will provide a model with general applicability for vertebrates, including ourselves.”
In Canada, the National Science and Engineering Research Council, the Canada Summer Works Program and the SFU Work-Study Program funded the research. The UK Biotechnology and Biological Sciences Research Council, the US National Science Foundation and the European Union (EU) Marie Curie fellowship also contributed funding.