Let’s get an idea of just how dominant arthropods are, by looking at how many of them there are.

• About a billion billion (1,000,000,000,000,000,000) insects are alive at any time. That’s about 160 million insects for each person on Earth!
  
• At any moment, there are about 1,000,000,000,000,000 ants alive on the planet. If each ant were half a centimeter long, they would form a chain long enough to circle the Earth 125,000 times!
• Tiny crustaceans called copepods, less than a centimeter long, are the most abundant animals in the ocean. There are so many of them, that they outweigh all the whales on Earth!