[2] Until 15,000 years ago, only common Bothrops lived by the island, which was at that time still connected to the continent due to the receded sea waters.

When the sea rose back again (with the end of the last glacial period) and the mountain returned to its archipelago status, the Bothrops that became isolated there quickly fed on all available rodents, which are its main food.

They ended up resorting to cockroaches and scolopendra and, due to their much smaller nutritional value, the snakes slowly shrunk their size until they couldn't grow beyond 50 cm – a process known as allopatric speciation.

[5] Found only on Ilha Alcatrazes, 35 km off the coast of São Paulo, southeastern Brazil.

Although Bothrops alcatrazt is relatively abundant on Alcatrazes, its range is very small (less than 1.35 km²), making it vulnerable to stochastic events.