Neuroethology Research on Insect Sensory Systems
We are interested in how insects use their sensory systems to detect and process information from their natural environments. We study bioacoustics, comparative neuroanatomy, electrophysiology, and behaviour to form an integrated view of an animal’s sensory world. The central focus of the Yack lab research program is on sound and vibration communication in insects.
Most butterflies are diurnally active, and much research has focused on how they use vision and chemical senses for communication and orientation. What about a sense of hearing? Do butterflies have ears?
Although hearing is has been extensively studied in moths that use their ears primarily to detect bat echolocation, hearing in butterflies is not well understood. Yet, many butterflies have miniature ears on their wings! We study the evolution, structure, function, biomechanics and neurophysiology of butterfly ears.
Hearing in Diurnal Butterflies
Thousands of species of Nymphalidae butterflies have tympanal ears, but at present, very little is known about the structure, function, and evolution of these ears. These species mostly hear in the same frequency range as humans, but since most butterflies don’t produce sounds, the function of hearing remains a mystery. We propose that they use their hearing to monitor their environment, and to detect predators such as insectivorous birds.
Hearing in Nocturnal Butterflies
The hedylids are nocturnally active ‘moth-like' butterflies that live in the neotropics. These butterflies also have ears on their wings in the same region as do diurnal butterflies, but they use them to detect and avoid bats. We are currently studying the neuroanatomy, physiology, and taxonomic distribution of these interesting ‘wing ears’, and how they evolved.
Links on hearing in butterflies:
Bark Beetle Communication
Bark beetles (Scolytinae) impose significant threats to forests throughout the world. While much research has focused on bark beetle chemical communication, little is known about how they use acoustics to survive.
Many species produce acoustic signals that have been implicated to function in defense, courtship, aggression, species recognition, and orientation. But, there is surprisingly little research on the characteristics and functions of these signals, and how they are received and transmitted. We use the mountain pine beetle (Dendroctonus ponderosae), the dutch elm beetle (Scolytus multistriatus), the pine engraver (Ips pini), and the red turpentine beetle (D. valens) to investigate sound and vibratory communication.
Links on bark beetle acoustic communication:
Caterpillars are important insects: they provide food to many predators but also can cause serious damage to forests and agricultural crops. Key to their success is an ability to communicate with their environment to facilitate foraging, defense, aggregation, shelter building, and competition for resources.
Surprisingly little is known about how caterpillars use sounds and vibrations to communicate.
One model organism for studying vibratory communication is the masked birch caterpillar, Drepana arcuata. Late instars live solitarily on birch leaves and use vibration signals to resolve territorial disputes over their shelters. Early instars live in social groups and are also very talkative!
Continuing research on this species and others that communicate using vibrations focuses on identifying vibration receptor organs and investigating the proximate mechanisms mediating vibratory mediated communication.