There are at least 368 species of hummingbirds worldwide, most in South America. Most hummingbirds are between 2 and 5 inches long, with even the heaviest hummingbird weighing less than an AA battery.

One of the hummingbird’s hallmarks is its long, narrow bill that's specialized to fit into tubular flowers. The shape suits their preferred nectar source, with some dramatically curved and others very long. To catch insects, the lower half of the bill flexes downward when opened. The fully opened bill then shuts around the insects like a snap trap.

To keep the fastest metabolism in the world fueled, hummingbirds need a prodigious amount of food. They eat half their body weight in sugar daily through meals every 10-15 minutes.

Hummingbirds see many colors that are invisible to humans due to an additional cone in their eye. This gives them the ability to see UV wavelengths and nonspectral colors.