Research Jana Goyens

Abstract

Balance is crucial during locomotion, and the challenges are largest in fast, agile and/or manoeuvrable animals. The vestibular system in the inner ear plays an important role in balance by sensing head movements. A popular line of research investigates anatomical adaptations of the vestibular system for enhanced sensitivity in agile animals. Yet, the actual effect of the observed anatomical features on sensitivity remains largely speculative. This project bridges all functional steps from vestibular anatomy to locomotor performance. First, I will quantify the effect of the anatomical differences on the vestibular sensitivity. The vestibular sense is used to stabilise the head during locomotion, so in a next step, I will test how increased vestibular sensitivity enhances head stabilisation in an experimental setup. Finally, I will assess whether a superior head stabilisation improves the locomotion performance and balance on runways of different levels of complexity. Because the balance requirements depend on the habitat complexity, locomotion style, and anatomy, this project takes an ecomorphological, comparative approach. By comparing lizard species that differ substantially in size, habitat, and agility, I will be able to assess the balance strategies of animals with different ecologies.

Researcher(s)

• Promoter: Aerts Peter
• Co-promoter: Goyens Jana
• Fellow: Jorissen Cas

Research team(s)

• Functional Morphology

Project type(s)

• Research Project

Abstract

Lacertid lizard species show a remarkable diversity in locomotion behaviours. Depending on their habitat and ecology, some species move in a highly dynamical and fast manner, while others are characterised by slow movements. Thus, their locomotor behaviours most likely pose different demands on their balance control. The 3 semi-circular (SC) canals of the vestibular system are crucial in this regard, because they sense rotational accelerations of the head. Hence, we hypothesise that the vestibular system is adapted to species-specific locomotion behaviour. We will perform a comparative study of the geometrical and functional properties of the SC canals of Lacertidae. The membranous SC canals are filled with endolymph fluid that deforms a cupula and its sensors when accelerated angularly. We will investigate the functional morphology of the 3 interconnected SC canals with Fluid-Structure Interaction computer models. We will thoroughly examine the functional consequences of the geometry (i.e. anatomy) and in vivo excitation (i.e. behaviour) on sensitivity and response time in lacertid lizards. This will facilitate future comparative studies, which are currently unequivocal in this regard. Usually, the bony SC walls are investigated, but we will focus on the membranous walls because these determine the vestibular system mechanics. To facilitate future studies, we will compare the geometry of the bony and the membranous morphology, and study the functional consequences.

Researcher(s)

• Promoter: Goyens Jana

Research team(s)

• Functional Morphology

Project type(s)

• Research Project

Abstract

Lacertid lizard species show a remarkable diversity in locomotion behaviours. Depending on their habitat and ecology, some species move in a highly dynamical and fast manner, while others are characterised by slow movements. Thus, their locomotion behaviours most likely pose different demands on their balance control. The 3 semi-circular (SC) canals of the vestibular system are crucial in this regard, because they sense angular accelerations of the head. Hence, we hypothesise that the vestibular system is adapted to species-specific locomotion behaviour. We will perform a comparative study of the geometrical and functional properties of the SC canals of Lacertidae. Usually, the bony SC walls are investigated, but we will focus on the membranous walls because these determine the vestibular system mechanics. To facilitate future studies, we will compare the geometry of the bony and the membranous morphology, and study the functional consequences. The membranous SC canals are filled with endolymph fluid that deforms a cupula and its sensors when accelerated angularly. We will investigate the fluid dynamical properties of the 3 interconnected SC canals with a Fluid-Structure Interaction model. We will thoroughly examine the functional consequences of the geometry (i.e. anatomy) and in vivo excitation (i.e. behaviour) on sensitivity and response time in lacertid lizards. This will facilitate future comparative studies, which are currently unequivocal in this regard.

Researcher(s)

• Promoter: Aerts Peter
• Fellow: Goyens Jana

Research team(s)

• Functional Morphology

Project type(s)

• Research Project