What is the total number of biodiversity hotspots in the world?

The 'Rivet Popper' hypothesis was proposed by $................$.

Based on the provided pie chart representing the diversity of invertebrates,which taxa represent the maximum and minimum proportions,respectively?

Identify the correct statements :
$1.$ According to $\text{IUCN} (2004)$,the total number of described species is slightly more than $1.5$ million.
$2.$ Robert May estimated the total species diversity on Earth to be around $7$ billion.
$3.$ Insects make up more than $70 \%$ of all recorded animal species.
$4.$ India,with $2.4 \%$ of the world's land area,contributes $8.1 \%$ to global species diversity.

Which part of the world has the highest population density of species?

How many genetically different strains of rice are there in India?