I. Exponential growth

Growth like that described above is called exponential growth. In exponential growth, the population increases by a constant multiplier (r) at each time step. You can see that the population grows slowly at first and then at a rapidly accelerating rate.

Exponential growth results from G = r * N, when r is a constant.

For those of you familiar with calculus, the integrated form of G = rN (dN/dT = rN) is Nt = Nort, where r = the exponent.

Human growth has not been not exactly exponential, because our r has not been constant. In fact, our growth has actually been faster than exponential, because r has generally increased over the course of human history.

(Click ">>" box to move to the next section (on sustainability questions) now; "<<" box to move to preceding section, "Contents" box to return to master directory for the BI301 web site. Or, use "Navigate .")