plotRicker(4, 0.3,    30, 'd-b');
hold on;
set(gca, 'fontsize', 12);
plotRicker(4, 0.3001, 30, 'x--r');
title('Ricker equation in chaotic regime: y_{n+1}=y_n e^{4 (1-y_n)}. \bf The "butterfly" effect.');
xlabel('x');
legend('y_0=0.3', 'y_0=0.3001', 'Location', 'Best');