Degree of biodiversity increases from

Given $S =$ species richness,$A =$ area,$Z =$ slope of the line,and $C =$ $Y$-intercept. If area is on the $X$-axis and species richness is on the $Y$-axis,what will the graph of $\log S = \log C + Z \log A$ look like?

As we move from the equator towards the poles,species diversity $.........$.

Alexander von Humboldt explored which region for his research on species-area relationships?

What did Alexander von Humboldt describe for the first time?

Species diversity increases as one moves from .......... .