xSt[] = 0; (* x starting position *)
 ySt[] = 0; (*y starting position *)
 years = 0; (* The years that pass *)
 endTime = 100; (* Amount of years until the end of time *)
 probLife = 0; (* The probability that life will sprout up *)
 nLife = 0; (* Amount of Circles of Life; and designation number *)
 circleLife[] = 0; (* Circle of Life *)
 rMulti = 0 ; (* Growth multiplier *)
 rBase = 0; (* Base growth rate *)
rGrowth[] = 0; (* Rate of Growth for each CoL *)
orgGrowth[] =
  0; (* Used to keep track of original growth rate assigned to \
specific life form *)

ContourPlot[x y, {x, -1, 1}, {y, -1, 1},
PlotRange -> {{-100, 100}, {-100, 100}},
PlotLabel -> Dynamic["Year = " <> ToString[years]],
Epilog -> Dynamic[plot[[1]]]]

For[years = 1, years < endTime,
  probLife = RandomInteger[{1, 10}];
 
  (* The following If function checks if there are any circles of \
life and if there is, begins updating them,
  as if the life form is expanding radially *)
  If[nLife > 0,
   For[n = 1, n <= nLife,
    n++,
    rGrowth[n] = rGrowth[n] + orgGrowth[n];
    plot =
     ContourPlot[((a - xSt[n])^2 + (b - ySt[n])^2 ==
        rGrowth[n]^2), {a, -100 \[Pi], 100 \[Pi]}, {b, -100 \[Pi],
       100 \[Pi]},
      PlotRange -> {{-100, 100}, {-100, 100}}];
    (* Pause[0.1] *)](* End For n *)
   ]; (* End If nLife *)
 
  (* The following If function checks if the probability of life \
forming is true and if so creates a new form of life at a random \
point on the plot and the size and growth rate of that life form *)
  If[probLife == 1,
   {nLife = nLife + 1;
     xSt[nLife] = RandomReal[{-100, 100}];
     ySt[nLife] = RandomReal[{-100, 100}];
     rMulti = RandomReal[{.01, .1}];
     rBase = RandomReal[{1, 10}];
    
     rGrowth[nLife] = (rMulti rBase);
     orgGrowth[nLife] = (rMulti rBase);
     plot =
      ContourPlot[((a - xSt[nLife])^2 + (b - ySt[nLife])^2 ==
         rGrowth[nLife]^2), {a, -100 \[Pi],
        100 \[Pi]}, {b, -100 \[Pi], 100 \[Pi]},
       PlotRange -> {{-100, 100}, {-100, 100}}]};
   ]; probLife = 0;(* End If probLife *)
 
  (* Pause[0.1]; *)
  years++;
  ] ;(* End For years*)