So far, scientists have identified about 1.2 million species of living creatures on Earth.
There may be about 8 million in all. The oceans are home to most species. Most of those on land are found in the tropical rain forests near the equator, which get lots of life-giving sunlight and water. But what we see today is just a fraction of the planet’s diversity, because more than 99 percent of the species that ever lived have died out over time.
