Scientists have proposed various hypotheses to justify the higher species diversity in tropics. They are as follows:

• Tropical regions have been relatively undisturbed for millions of years compared to temperate region which have been subjected to glaciations in past which led to higher species diversification as it got more evolutionary time.

• Tropical regions have more constant and predictable climate compared to temperate which can promote niche specialization and higher species diversity.

• Solar energy is available more to tropics causing higher productivity and leading to higher diversity.