Which of the following ecologists proposed the 'rivet popper' hypothesis?

How many bio-geographical regions are present in India?

In India, we find mangoes with different flavours, colours, fibre content, sugar content and even shelf-life. The large variation is on account of

According to the representation of global biodiversity proportions for the number of species of major taxa of vertebrates,select the appropriate option for the labels $X$,$Y$,and $Z$ in the given figure.

Invertebrates constitute what percentage of the animal kingdom (in $\%$)?

What is the value of the $Z$ line (regression coefficient) in the context of bird species richness in California?