co-evolution
Co-evolution is frequently seen in pairs of species that interact
frequently or closely.
A change in the traits of one species acts as a selection pressure on
the other species.
activity 1 - co-evolution
Your task is to research the examples of co-evolution shown on the
following slides.
Be prepared to discuss your findings at the next lesson.
pollinators and plants
mutualistic co-evolution
mutualism
mutualistic co-evolution
herbivores and plants
competitive co-evolution
seed-eater and plant
competitive co-evolution
predators and their prey
competitive co-evolution
parasites and their hosts
competitive co-evolution
the ‘arms race’
activity 2 – the ‘arms race’
You will now read and discuss an article on the ‘arms race’ between the
human host and the parasite Plasmodium falciparum.
malaria’s evolutionary arms race
the red queen hypothesis
The co-evolutionary ‘arms race’ between a parasite and host is known
as the Red Queen Hypothesis as both organisms must ‘keep running
in order to stay still’.
At the top of the hill, the Red Queen begins to run,
faster and faster. Alice runs after the Red Queen, but
is further perplexed to find that neither one seems to
be moving. When they stop running, they are in
exactly the same place. Alice remarks on this, to
which the Red Queen responds: "Now, here, you see,
it takes all the running you can do to keep in the same
place".
malice in wonderland
the red queen hypothesis
Hosts better able to resist and tolerate parasitism have greater fitness.
Parasites better able to feed, reproduce and find new hosts have
greater fitness.
parasitic wasp / housefly PPQ