Co-evolution Flashcards
What is the definition of co-evolution?
The process by which two or more species evolve in response to selection pressures imposed by each other
What does the change in the trait of one species do to others?
It acts as a selection pressure on the other species
Where is co-evolution frequently seen?
In pairs of species that have symbiotic interactions
What is an example of co-evolution?
Humming birds have beaks that evolved to allow them to drink from a certain kind of flower. In return the flower species it feeds from has evolved to produce nectar especially tasty to hummingbirds
What is the definition of symbiosis?
Co-evolved intimate relationships between members of two different species
How can the impacts of symbiotic relationships effect the individuals involved?
It can be positive, negative or neutral
What are the different types of symbiotic interactions?
Mutualism
Commensalism
Parasitism
What is the definition of mutualism?
Both organisms are interdependent on each other for resources or other services. As both organisms gain from the relationship, the interaction is (+/+). An example of this would be clown fish and anemones
What is the definition of commensalism?
Only one of the organisms benefit (+/0). An example of this is cattle egrets follow cattle herds eating the insects disturbed by the moving cattle, the cattle gain no benefit.
What is the definition of parasitism?
Parasite benefit in terms of energy or nutrients and the host is harmed as the result of the loss of these resources (+/-). An example of this is mosquitos and humans
What does the red queen hypothesis state?
It states that in a co-evolutionary relationship, change in the traits of one species can act as a selection pressure on the other species. This means that species in the these relationships must adapt to avoid extinction
What is an example of the red queen hypothesis?
Plants develop toxins to kill caterpillars. Caterpillars will die off but some will survive who are immune. The plant then has to evolve more toxins to overcome the caterpillars
