"Ever-changing" is the correct term, as it is used to describe something that is constantly evolving or in a state of continual flux.
Gene Flow
The allele frequency of the populations gene pool is changing.
a population of bacteria is changing exponentially according to the function below. how can you describe the bacteria population? B(t)=1200(0.99)8t+6
There's no particular scientific term, but you might use 'warping'.
Population density is a term used to describe how crowded a place is based on the number of people per unit of area.
minority
a population explosion population of course der stupid
"Boom" is used to describe a sudden growth in the population of a city.
"Acceleration" is the term used to describe motion whose speed, or direction, or both, are changing.
The "average" of the population of samples is the same as their "mean".
A term political scientists might use to describe groups within a population is demographics. Demographics take not of the different types of people that live in an area along with other information like income.