The world’s smallest bird egg is laid by the world’s smallest bird – the bee hummingbird. The egg is 0.275 inches long and weighs only 0.0009 ounces.

Bee Hummingbird

It should come as no surprise that the largest bird egg is laid by the largest bird – the ostrich. The heaviest ostrich egg on record was laid by a captive individual. The egg weighed 5 lb 11.36 ounces. 

Ostrich hen 

Sea turtles always return to the beach where they were born in order to lay their eggs. For example, on a specific Costa Rican beach each October, tens of thousands of sea turtles crowd the beach in an event known as the arribada or “arrival.”

Sea Turtle

Like all reptiles, these aquatic creatures lay their eggs on the ground. They make nests on the riverbank, and the mother stays nearby to protect the nest and newly hatched offspring.

Crocodiles

Some snakes, such as the garter snake, are ovoviviparous – young form inside an egg and are fed by the egg yolk, but the egg is retained inside the mother’s body rather than being laid in a nest. 

Green Tree Python Snake

Frogs, toads, and other amphibians lay their eggs in water. The eggs do not have hard shells. Instead, they are laid in a mass with the texture of jello.

Frogs 

Most spiders place their eggs in a sack made of spider silk. These may be hidden underground or supported by the web. But a few spider species take their eggs with them.

Spiders 

The Seahorse’s mating and birthing are one of the wonders of nature. After the courtship is over, in a reversal of role, the female seahorses deposit their eggs in the males’ brood pouch.

Seahorse 

 Monotremes, are mammals that lay eggs. The mother carries the eggs inside her body for a time, providing the nutrients. She lays the eggs in a nest or den, and they hatch about 10 days later.

Monotremes