Hummingbird eggs are incredibly small and delicate and are typically about the size of a jellybean, small pea or blueberry. They usually measure around 1.5 centimeters (0.6 inches) in length and about 1 centimeter (0.4 inches) in width. Each egg weighs less than a gram, usually around 0.5 to 1 gram. 

Hummingbirds build tiny, cup-shaped nests usually made from plant fibers, spider silk, and lichens, which provide a secure and camouflaged environment for their eggs. The nests are often about the size of a golf ball. Typically, a female hummingbird lays two eggs per clutch, and she incubates them for about 14-23 days until they hatch. 

Fun Facts:

Hummingbirds are the world's smallest migrating birds, weighing less than a nickel. Despite their small size, hummingbird nests are strong and flexible, allowing them to expand as the chicks grow. The use of stretchy spider silk in the nest construction helps accommodate the growing birds without the nest falling apart. 

Hummingbirds are the only birds that can fly backwards. They can also travel long distances, with some species crossing the Gulf of Mexico in one flight of up to 600 miles. Hummingbirds have the largest brain-to-body proportion of any bird, with their brain making up about 4.2% of their body weight. 

Hummingbirds migrate individually, and male hummingbirds migrate first. They enter a state of torpor during migration to save energy for the next leg of the journey. 

Flowers are the main food source for hummingbirds, but they also drink nectar from feeders by moving their tongue in and out about 13 times per second. 

The Ruby-throated Hummingbird, for example, can visit more than 1,000 flowers in a day, consuming up to half its weight in nectar between sunrise and sunset.