This microstate borders one of Europe’s most biodiverse mountain ranges but is the least biodiverse country in the world – here’s why

At around 61km² San Marino, in Europe, is one of the world’s smallest countries. Entirely landlocked, it is surrounded by Italy.

It does, however, have a surprising variety of habitats given its small size. These include woodland, farmland, rivers and mountainous terrain.

• This country is the most biodiverse on Earth – although scientists don't know exactly why

• Scientists looked beneath one of oldest trees on Earth. What they found is astounding
• It’s bigger than Florida, straddles 3 countries and is home to a snake as long as a great white shark

But despite its variety of habitats, San Marino is one of the least biodiverse countries. This is largely because of its small size, its landlocked borders (marine and intertidal habitats tend to support many species) and extensive human development.

Altogether, the micro-state has about 88 native bird species, 41 native mammals, 10 native amphibians, 14 native reptiles and eight native fish, as detailed in a 2021 report by the Republic of San Marino.

For comparison, Brazil – one of the world’s most biodiverse countries – has more than 1,500 native bird species, over 700 native mammals, and about 1,000 native amphibians, 700 native reptiles and 3,000 native fish.

It’s important to note that we have not yet discovered all the species in the world. So, while we can make a best guess about a particular country’s native species, there is still a lot for us to learn.

Top image: San Marino's Falesia tower. Credit: traumlichtfabrik/Getty Images