How Differences Evolve Within Species
Biologists recognize that, within a species, evolution does not lead to any single “best” male or female phenotype (trait). Instead, many animal species exhibit widespread differences in reproductive or behavioural traits among individuals; these alternative reproductive traits are believed to play a fundamental role in creating biodiversity. Our knowledge of exactly how these traits are expressed, however, is still limited.
Dr. Clint Kelly, Canada Research Chair in Behavioural Ecology, is tackling this puzzle by studying various insect species. One is the Wellington tree weta. Males of this large, flightless, cricket-like New Zealand insect exhibit major differences between individuals—some males, for example, have large jaws that they use to fend off rivals over access to females, while others without this trait are have adapted to sneak surreptitiously into groups of females. How such differences develop and are passed along remains a mystery of this and many other species.
Kelly’s research will offer insights into the evolution of such alternative traits, identifying how genetics, hormones and nutrition affect individual growth and development. In addition, Kelly’s research will measure and identify individual behaviour and establish how different species—and populations within species— vary in appearance and behaviour.
This research will provide deeper understanding of different traits in biology, and will shed light on their roles in the evolution of species.