Mod 4 - ENT 101

Passive Dispersal

Movement of an organism assisted by external sources.

Invasive Species

Organism that is not native to a specific location, and which causes damage in some way in its new range to the environment, the economy, or human health.

Phoresy

Movement of one organism that is being transported by another, without a parasitic relationship.

Active Dispersal

Movement of an organism powered by its own musculature, without the assistance of external sources.

Apodemes

Thick internal ridges of the exoskeleton that provide support for the internal organs and attachment points for muscles and tendons.

Resilin

Elastic protein which functions similarly to tendons in vertebrates.

Hydrostatic Skeleton

Structure supported by the pressure of fluid contained within it for insects that don’t have a rigid exoskeleton.

Parts of the Leg

Coxa, trochanter, femur, tibia, tarsus, and pretarsus.

Tripod Gait

3 legs remain in contact with the ground and centre of gravity remains balanced.

Cursorial Legs

Allow long strides and the leg segments are slim to reduce weight and increase stride frequency.

Raptorial Legs

Modified for grasping and holding, and the tibia and femur often feature spines to assist the grip.

Fossorial Legs

Forelegs modified for digging, with a flattened, enlarged, and hardened tibia that have tooth-like projections.

Saltatorial Legs

(Hind legs) have enlarged femurs and tibias to store energy to launch the insect.

Natatorial Legs

(Mid or hind legs) segments are flattened with rows of setae or hairs to act like oars.

Proleg

Modified extensions of the body wall to improve grip on substrate. They are not “true legs” as they are not attached to the thorax and do not bear the six segments.

Paeloptera

“Old wing” and refers to the ancestral state of being unable to rotate the wings so they can be folded over the abdomen.

Neoptera

“New wings” in which they have flexion lines that allow them to be folded flat over the abdomen. Protected from physical damage and makes insect more compact.

Tegmina

Modified forewings used for protection, and asymmetry in the beats help steer the insect in flight.

Hemelytra

Half leathery, half membranous wings.

Elytra

Forewings that are completely sclerotized to form protective structures. They are unique to coleopterans.

Halteres

Reduced hindwings modified into small, knobbed stalks that help to improve stability.

Direct Flight Muscles

Flight muscles attach directly to the sclerites to power wing movement.

Indirect Flight Muscles

Flight muscles attach to anterior, posterior, dorsal, and ventral regions of the thorax, rather than directly to the wing bases.

Dorsoventral Muscles

Powers upstroke of wing.

Dorsal Longitudinal Muscles

Powers downstroke of wing.

Click Mechanism

Mechanism in insect flight that uses the elasticity of the thorax to store and release energy between wing strokes.

Synchronous Muscles

Muscles that produce one contraction cycle per nervous impulse. Less than 100 beats per minute.

Asynchronous Muscles

Muscles which produce multiple contraction cycles with a single nervous impulse. More than 100 beats per minute.

Migration

Direct and persistent movement of an animal towards a more suitable habitat driven by the animal's own efforts, during which the animal is unresponsive to to most stimuli.

1. Persistent movement away from home using animal’s locomotion.

2. Relatively direct movement toward a destination.

3. Generally unresponsive to stimuli.

4. Distinguishable pre- and post-migration behaviours.

5. Physiological changes in allocation of energy for biological processes.

Migratory Syndrome

Suite of pre-migratory behaviours and traits that predispose an organism to long-distance movement.

Oogenesis-Flight Syndrome

Delay of reproductive processes due to resource allocation to migratory traits over reproduction.

Locusts

Name given to the migratory form of some grasshopper species, which form under high population densities and poor environmental conditions, and have physiological, behavioural, and physical differences from the solitary form.

Swarm

Cluster of many insects.

Polyphenism

Phenomenon where two or more distinct phenotypes are produced by the same genotype.

Phenotypic Plasticity

Presence of multiple forms, or phenotypes, within a species or population dependent upon environmental conditions.

Citizen Science

Practice in which non-professional members of the public are guided by professional scientists to aid in experiments, data collection, or other aspects of scientific studies under standardized protocols.