Phenotypic Evolution in Water Striders - An EvoDevo Perspective

Explore the evolutionary and developmental biology of water striders in this comprehensive lecture. Delve into an integrative approach to animal diversity, comparing walking and rowing adaptations. Examine how the timing and dosage of Ubx gene expression modulates leg length, impacting speed and escape strategies. Investigate niche specialization and evolutionary innovations, focusing on the propelling fan structure. Learn about taxon-restricted genes controlling fan development, including geisha and mother-of-geisha. Discover the genetic correlation between exaggerated weapons and their use in Microvelia longipes, a model organism for studying trait exaggeration. Gain insights into how these adaptations disproportionately scale to body size and influence mating success in different competitive scenarios.

Intro
An integrative approach to the study of animal diversity
Walking vs Rowing
Timing of Ubx expression modulates leg length
Evolution of Ubx function and leg length
Dose of Ubx expression modulates leg length
Increased leg length and speed
Increased leg length and escape strategy
Niche specialization and evolutionary innovations
Propelling Fan: evolutionary innovation
Fan: genetic origin of evolutionary innovations
Two taxon-restricted genes control the fan
geisha and mother-of-geisha control the fan
gsha/mgsha RNAi fan function is specific
What is the role of the fan?
Take home message
Scale disproportionately to body size
Microvelia longipes: a new model to study trait exaggeration
Large males dominate win contests
Small males fertilise more eggs when competition is lower
Genetic correlation between the exaggerated weapon and its use!