Class Notes (809,025)
Canada (493,492)
Biology (6,677)
Biology 1001A (1,723)
Tom Haffie (1,166)

L22 – Arms Race and Virulence

4 Pages
Unlock Document

Western University
Biology 1001A
Tom Haffie

L22 – Arms Race & Virulence Adaptive Radiation is a fairly rapid mode of speciation - kicked off by competitive release (new environment, mass extinction) - ecological opportunity - evolutionary innovations can induce adaptive radiation (ex. Using animals as pollinators gives new opportunity to both branching lineages of flowers as they both now have opportunity to grow) - flowers with different phenotype/temporal blooming will become reproductively isolated as they attract different pollinators or pollinators that operate at different types of days - pollinator isolation  prezygotic isolating mechanism Angiosperms are very diverse due to wide variety of speciation opportunities given by physical characteristics as well as temporal qualities that determine which animals pollinate them. Benefit for Plant - new combination of genes - gets to have sex - plants are immobile so this is ideal for plant Benefit for Animal - behaving altruistically? - gets food (nectar of flowering plant) Interaction of different species - both benefit = mutualism (ex. Plant & Flower benefit) (ex. Domestication of animals and crops by humans) - both suffer = competition * two or more species competing for limited resource * coexisting species in an area will compete for resource (overlapping cheetah/lion range compete for food resources) ( animals competing for water) * each party is worse off due to presence of other species * intensifies competition for resource (Ex. Plants compete for space, water, soil nutrients, for sunlight, become TALL to grow and obtain light energy) - one benefits, one suffers = antagonism * one exploits the other; natural enemies * Predator/Prey Relationship * Host-parasite relationships * Disease causing organisms (Parasites/Pathogens benefit at the expense of host individual) ^^ Any of these types of relationships can give rise to an…. Evolutionary Arms Race - adaptation by one species improves its ability to interact with another - can improve ability to exploit or benefit other species - selection pressure on the second species to evolve counter- adaptation  reaction to adaptation of first species - ex. Evolution of a toxin = adaptation of newt, garter snake counter adaptation = evolving to be resistant to toxin of newt. Newt will subsequently evolve to produce more toxin and the snake becomes better at breaking down toxin. Evolutionary arms race. - Newt invests resources in adaptation which takes resources AWAY from reproductive success - Metabolic enzymes to break down toxins is tradeoff for energy needed to reproduce - Evolution > reproduction however it i
More Less

Related notes for Biology 1001A

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.