A certain species of plants serves as the only food for the young larvae have a particular species of butterflies in a large field a disease kills all the members of this plant species as a result of the plant disease the butterfly population will most likely One quickly adapt to each other plans or to disappear from the area or three evolve to form a new species or three into the adult stage more quickly

Dissappear from the area

Explanation:

As the specific species of plants is only source of food for the butterfly larvae, if anything happenes to the food source (in this case disease occurred that killed the food source for the butterfly larvae) results in the larvae starving to death. During this short period of time, butterflies cannot undergo enough mutations to have the ability to ingest another good source. Hence, the butterflies in adult stage will slowly die off due to them reaching the end of their lifespan, while the larvae which cannot ingest any other species of plants will die off before reaching maturity, resulting in the butterfly species to dissappear form the area.

Butterfly cannot adapt to each other because it cannot adapt to change food source due to its niche.

Evolving to form a new species can only occur within millions of years whereby the species will accumulate enough mutations to change its phenotype. However, butterflies have a short lifespan and having the only food source of their young to be diseased that causes the food source to die off, the young cannot survive to maturity and dies off, resulting in the butterfly species to not be able to survive long enough for enough mutations to occur in order to evolve.