J-shaped or Exponential Growth Curve
In species or situations where this type of growth form is permitted, population density increases rapidly, in exponential form (It is called exponential because the rate of increase can be expressed as a constant fraction, or exponent, by which the existing population is multiplied). The more individuals are added to the population, the faster it increases, because all those that are added also breed and hence increase the total growth rate of the population.
CMP Bio World 