Which event shows the pattern of coordinated stasis? a) the removal of geographic barrier united species that were previously reproductively isolated. b) major hurricanes and other weather variations destroyed regions of coastline ecosystems. c) the volcanic eruption of mount st. helens in 1980 spewed vast amounts of ash into the air. d) global cooling 2.8 million years ago resulted in dry grassland replacing wet forests in parts of africa.

The correct answer is: d) global cooling 2.8 million years ago resulted in dry grassland replacing wet forests in parts of Africa.

Coordinated stasis describes that certain groups of species don’t change for tens of millions of years and then experience the rapid extinction and the formation of new species. Coordinated stasis is related to punctuated equilibrium where communities of species closely interact and because of that don’t evolve. Instead of that, they respond to environmental change by moving as a group to a different location.  

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.