A biologist spent many years researching the rate of evolutionary change in the finch populations of a group of islands. It was determined that the average beak size (both length and mass) of finches in a certain population increases dramatically during an intense drought between 1981 and 1987. During the drought, there was a reduction in the number of plants producing thin-walled seeds. The biologist discovered that from 1988 to 1993, the average beak size declined to pre-1981 levels. The reversal in beak size from 1988 to 1993 was most likely related to which of the following events

the end of the drought

Explanation:

According to the study of finch populations on the island of Daphne Major it has been discovered that evolution occurs by natural selection when the finches' food supply changes during droughts. change in the environment has influenced the opportunities for speculation and diversification of finches. Studies have shown that rapid changes in these finch birds’ beak sizes and shapes are as a result of sudden environmental variations such as drought, or human disturbances. The reversal in beak size is mostly related to the end of the drought,

organ system-an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.