Complex sentence: The Bermuda Land Snail is an endemic species of pulmonate land snail that scientists believe colonised the mid-Atlantic island of Bermuda at least 300,000 years ago and make up 95% of Bermuda's terrestrial fossils.
Split into simpler sentences: The Bermuda Land Snail is an endemic species of pulmonate land snail that scientists believe colonised the mid-Atlantic island of Bermuda at least 300,000 years ago. It makes up 95% of Bermuda's terrestrial fossils.