There are more than 170 countries in the World. Out of these 12 alone harbor in between 60 and 70% of the total biodiversity of the planet and thus earn the privilege to be called megadiverse.
Mexico is one of them.
Why is Mexico Megadiverse?
Most megadiverse countries lie in tropical regions. Tropical regions are more biodiverse. With exception of the northern part of the country, Mexico lies in the tropics extending from 32° North above the Tropic of Cancer (Baja California Norte) south to 14° Norte (Chiapas).
When the landmasses of North and South America first made contact roughly 3 million years ago, and became joined by the Isthmus of Panama, a transition zone with a rich mixture of fauna and flora originated. This unique zone is a belt stretching from coast to coast over today’s Mexico. Central and western flyways of North American bird migrations pass through Mexico, enriching its avifauna during the winter months.
Complex geography always translates into diversity of habitats, soils and climates. Mexico is an extremely varied country with oceans on both sides and great altitudinal range.
Larger countries have bigger diversity of habitats, which means more species. Mexico is 14th largest country on the planet with 1,972,550 km2.
Glaciation and Island Effect
There are dozens of islands on Mexican territory. These are often home to unique species of animals and plants. Unique species can also be found in so called glacial refugia – geographic regions which made possible the survival of flora and fauna in times of ice ages.