Some species of hummingbirds have different shapes of beaks that evolved to allow them to drink from certain flowers. the flower species have evolved to produce nectar that is tasty for the hummingbirds. this example is a type of (coevolution, convergent evolution, adaptive radiation). cuckoos lay eggs in the nests of other birds. the cuckoo lays eggs identical to the eggs of the host species, so the other bird takes care of it. this is an example of (mutualism, parasitism, adaptive radiation).

1. Coevolution, 2. Parasitism

Explanation:

1. Coevolution is the process by which two or more species evolve simultaneously by exerting selection pressure on each other. This evolution can be seen among organisms of distinct species which lives in close proximity. This can be seen among predators and prey, parasites their hosts and mutualistic relationships . The given situation is an example of coevolution. The humingbirds and flower species evolve simultaneously so as to meet the demands of the mutualistic relationship.

2. Parasitism is a phenomena in which one organism is dependent upon other organism for food, shelter and other needs. In this relationship the parasite only receives the benefit but the host gets harm.

Cuckoos are brood parasites which meets they produce eggs which mimic the eggs of the host bird in shape, color, and size. This make the host unaware of the fact that it is rearing the young ones of the other bird too.  

"a.) well–developed vascular system."