From the graph, we can also see that the y-intercept is 6, therefore we can say that the equation of the straight line is \ (y = mx + 6\). Now we need to find the gradient.

Journal of Biogeography, Vol. 30, No. 6 (Jun., 2003), pp. 827-835 (9 pages) Aim This paper reviews possible candidate models that may be used in theoretical modelling and empirical studies of ...