More than 300 million years ago, before the age of giant dinosaurs, Earth was home to giant insects.

The Carboniferous period was one of the most transformative periods in Earth’s history. The planet’s vast landmasses are beginning to form the supercontinent Pangea. Vast swamps and warm, humid forests dominate the landscape. And giant insects aren’t the only giant creatures roaming the planet. There are also plenty of sea creatures, like early forms of sharks and a giant amphibian.

Now, the first thing you will probably notice will be the giant insect-like creatures. One of the most iconic is megaeura. This insect resembles modern-day dragonflies, except for one big difference. It has a wingspan of up to 75cm. Even scarier than that, it is a carnivore, hunting insects and other small amphibians.

In our planet’s ancient history, there was a time when Earth was home to some of the most incredible creatures you can imagine. This was the age of giant insects, when dragonflies had wingspans like eagles and millipedes were longer than a human arm. Comparing giant insects of the past with modern insects reveals astonishing changes in Earth’s ecosystem over millions of years.

Another scary-looking insect is the pulmonoscorpius. This is a giant scorpion that mainly roams swampy areas on Earth. They can be up to 70 cm long. There are also giant cockroaches up to 10 cm long and mayflies with a wingspan of 45 cm.

Scientists believe that high oxygen levels, the absence of large vertebrate predators, and evolutionary adaptations all contributed to insect gigantism during this time.

As Earth’s climate and vegetation changed and as larger vertebrate predators evolved, the age of giant insects gradually came to an end. Smaller, more agile insects eventually took over.

Giant Millipede Arthropleura, a giant centipede, can grow to more than 2 meters long. Despite their fearsome size, they are herbivores and pose no danger to humans.