Planet Earth is full of more natural wonders, amazing animals and peculiar plants than we humans can count — and, since an estimated 86 percent of the world's species have yet to be discovered, there's more out there than we may ever know about. But many of the ecosystems and the life forms they support — from tiny, microscopic insects to great blue whales — are at risk due to shifts in weather patterns, climate change and human impact. Here, to celebrate Earth Week — and Earth Day on April 22 — illustrator Candace Rose Rardon looks at four of the world's most beautiful ecosystems: where they are, why they're at risk, and why they're worth protecting (click to enlarge).

World ecosystems

Getting there

Whether you're interested in a tour of the Amazon, a safari on the African savannah, snorkelling in the Great Barrier Reef of a day in New Orleans, G Adventures can get you there. We're excited at the prospect of showing you more of this big, beautiful world — and inspiring you to engage in sustainable, responsible travel with us. Check out our full selection of small group tours here.