Research Katleen Huyghe

Abstract

Animals communicate with members of their own and other species through an astonishing array of signals and displays. Just like any other biological characteristic, the organs and structures that send out and pick up signals and the signals themselves are believed to evolve. Natural selection is thought to tune communication channels according to the physical and biotic particularities of the local environment. In this project, we aim to investigate the role of the physical environment in the evolution of a chemical communication system. Lizards of the family Lacertidae deposit pheromones that contain information on the sender's species identity, its sex and its quality as a rival or sexual partner. These chemical cues are packed in a waxy substance produced by special glands on the inner thighs of the animals (the femoral glands). The lizards actively or passively deposit the femoral secretion on objects in their home range. Conspecifics pick up the cues by means of their forked tongue, which delivers the chemical particles to a specialised chemosensory organ (Jacobson's organ) in the roof of the mouth. Lacertid lizards inhabit a wide variety of habitats, from tundra over rain forests to sandy deserts. We will investigate whether and how this range of physical conditions has affected the organs producing the signals (femoral glands), the receptive system (tongue, Jacobson's organ, brain) and the chemical signal itself (physical characteristics, chemical composition).

Researcher(s)

• Promoter: Van Damme Raoul
• Co-promoter: Huyghe Katleen
• Fellow: Van Moorleghem Charlotte

Research team(s)

• Functional Morphology

Project type(s)

• Research Project

Abstract

I want to continue the artificial selection experiment that constituted the core of my first FWO-post doc mandate. In short, the experiment involves selecting male guppies (Poecilia reticulata) for dominance and for sexual attractiveness, respectively. The project is original in that it contrasts effects of intra- and intersexual selection on male phenotypes and because of its unconventional methodology (artificial selection). The experiment is currently running at full speed and the results are highly promising. After only three generations, males from the experimental lines already differ from one another and from control lines in their colouration, morphology and behaviour. It is my intention to follow up the system for at least another three generations, to see whether the evolutionary trajectories taken continue to diverge. I also want to explore whether divergent artificial selection on male phenotypes ('dominant' versus 'attractive') induces concomitant changes in female mate choice and the mate choice mind.

Researcher(s)

• Promoter: Van Damme Raoul
• Fellow: Huyghe Katleen

Research team(s)

• Functional Morphology

Project type(s)

• Research Project

Abstract

Sexual selection favors the evolution of traits that affect the reproductive success of individuals, traits that are important in male combat and male signals used by females during mate choice. As even small differences in these traits can result in a large variance in reproductive success, their evolution can be rapid and apparently unlimited. Differentiation of these traits may occur in populations with varying social conditions (e.g. density, sex-ratio) and the hypothesis of speciation by sexual selection states that when a parallel change in female mate preference and male sexual traits occurs within a population, this population might become reproductively isolated from others. With this project I will test this hypothesis, and investigate the role of sexual selection mechanisms in population divergence, and ultimately speciation. Therefore, I will use a dual approach. First, I will conduct a comparative study of natural populations of the Dalmatian wall lizard Podarcis melisellensis to describe the variation in sexual traits among populations of varying density and compare it with neutral variation and variation in naturally selected traits. Second, I will test to what extent sexual traits diverge when the social environment of a population is manipulated. This will be done by experimentally manipulating the density and sex-ratio of killifish populations (Austrolebias sp.) under laboratory conditions.

Researcher(s)

• Promoter: Van Damme Raoul
• Co-promoter: Aerts Peter
• Fellow: Huyghe Katleen

Research team(s)

• Functional Morphology

Project type(s)

• Research Project