mosquitoes Flashcards
What are sibling species
closely related, morphologically identical, reproductively isolated, behaviourally/ physiologically or ecologically different in some way
How do sibling species arise
isolation between a single population, random mutations drive genetic divergence which causes reproductive isolation
How can a population be isolated
Physically
Ecological niche separation
Behavioural changes
Define cryptic species
morphologically identical but different behaviours / ecological niches
species complex
morphologically indistinguishable (cryptic sibling species) that exhibit some form of reproductively isolating mechanism
Cryptic species can differ in…
Vector competence host preference behaviours physiology (which influence vectorial capacity and methods of control)
Why is it important to understand taxonomic complexities in vectors?
- targeting correct species for control
- monitoring spread of IR
- implementing genetic control strategies
How are sibling species recognized?
- lab crossing experiments
- karyotype
- dna sequence analysis
- protein analysis
4 groups insecticides
Pyrethroids
organochlorines
carbamates
organophosphates
most common synthetic pyrethroid
deltamethrin
how do ddt and pyrethroids work
target Na channels on axons, delay channel closing so constant firing
how to organophosphates and carbamates work
target acetyl cholinesterase at synapses, prevents breakdown of acetylcholine
how do organochlorines work
target GABA receptors
Definition of operational resistance
The selection of a heritable characteristic in an insect population that results in the repeated failure of an insecticide product to provide the intended level of control recommended.
Define developing resistance
the development of an ability to tolerate doses that would prove lethal to a majority of individuals in a normal population of the same species
