Insect Locomotion Flashcards
What are the two hypotheses in wing development called?
Paranotal hypothesis: wing is a new structure
Limb branch hypothesis: wing emerged from an existing structure
Give some advantages of wing development
Protection for legs Covers for spiracles Thermoregulation Sexual display Concealment Predator avoidance
What were the three genes studied in wing development?
Wingless, vestigal and apterous
What do direct flight muscles do?
Power flight in big insects and wing attitude in smaller insects
What happens when the elevator muscle in the direct flight muscle contracts?
The wing is elevated (upstroke)
What happens when the depressor contracts in the direct flight muscle?
The wing is moved downwards
What do the indirect flight muscles do?
Provide the majority of propulsive force (lift) in most small holometabolous insects
What do the two antagonistic muscles in the indirect flight muscles do?
Dorso-ventral muscles flatten the thorax causing wing upstroke
Longitudinal muscles shorten the thorax causing wing downstroke
What is asynchronous activation?
More than one contraction per action potential/spike in a wing motor neuron
What is synchronous activation?
One wing beat per action potential (can’t exceed 100bps)
What nervous reflex usually initiates flight?
The tarsal flight reflex when the tarsi lose contact with the ground
What do the rheosensors and chordontal sensors do?
Rheosensors: maintain flight
Chordontal sensors: adjust flight
What are the two phases of walking?
A stance phase and a swing phase
What is the general step of an insect called?
Tripod gait
