Spring in Southern California means some of the world's tiniest birds build some of the world's dinkiest nests. Female hummingbirds gather moss, plant down and other materials and, using sticky spider silk, fashion a nest the size of a ping-pong ball. It can rest securely on a very slender tree limb. But hummingbirds have been known to nest in railings, beneath bird baths, on wind chimes and cactuses.

Los Angeles Times photographer Irfan Khan found this hummingbird nest at the Los Angeles County Arboretum and Botanic Garden in Arcadia. Scroll through the photos -- and some amazing hummingbird facts -- let us know your favorite shot in the comments. (Mine's at the end.)

A hummingbird's heart beats an average of 1,260 times per minute. A human's heart beats about 70 times a minute; an elephant, 30 times.

The fast-beating heart is matched by fast-flapping wings, which can flap 70 times per second. To fuel all that motion, a hummingbird can eat one-half to eight times its body weight in nectar in a day.

Hummingbird eggs are the smallest of all bird eggs. The vervain hummingbird holds the record -- a mere 0.39 inches long and weighing only 0.0128 ounces. The largest eggs are laid by ostriches, and they weigh 5 pounds, 11.36 ounces.

Female hummingbirds lay one to three eggs, and the babies fly in 18 to 30 days.

Sources: Defenders of Wildlife, World of Hummingbirds, Guinness World Records.

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