As the only living member of a primitive order of gymnosperms (Ginkgoales), the ginkgo tree is a stalwart survivalist. The tree is native to China and is scientifically described as Ginkgo biloba. Fossilized leaves of ginkgo relatives have been found distributed widely around the world and some date back more than 200 million years ago. The reason that the ginkgo has outlived its relations is not known for certain, but it is thought that populations of the gymnosperms declined greatly around 60 million years ago and China became the final habitat of the ginkgo. Millions of years later, the appearance of humans may have helped the ginkgo endure, since the trees have been planted in Chinese temple gardens since antiquity. Today the ginkgo is planted in a wider variety of locations as an ornamental tree and is able to thrive even in polluted urban areas.