by: Ken Byrne
The ostrich is a member of the Ratite family, which also includes emu, rhea, cassowary, and kiwi. Ratites are distinguished as flightless and keel-less (having no breast bone) birds. Ostrich skeletons and fossils date back over 120 million years.
The ostrich, native to Africa, is the largest of living birds. Some males reach a height of 8 ft (244 cm) and weigh from 200 to 300 lb (90 – 135 kg), while females will range between 5.5 and 6.5 (170 cm – 200 cm) feet tall at maturity.
In the wild, a mature female will lay between 12 and 15 eggs after mating (at the rate of one every other day for several weeks). Ostrich farmers quickly remove the eggs from the nest to extend the laying season. In some cases, a domesticated hen can lay up to 80 eggs, although 40 to 50 is more typical. Ostrich eggs are the largest of all bird eggs and weigh about 2.75 pounds (1.2 kg). The contents of one ostrich egg can be equivalent to as much as two dozen chicken eggs. Both male and female ostriches share sitting responsibilities, usually the male at night and the female during the day. Fertile eggs begin to hatch on the 42nd day.
Ostrich eggs are as beautiful as they are fascinating, and they are surprisingly durable. Artists paint them, cut them and even decorate them with intricate carving. The Bush Men of the Kalahari Desert use them as sturdy canteens that can hold about 1.25 liters of water.
Educational Innovations has ostrich eggs that have been emptied through a hole in one end and thoroughly cleaned. The somewhat mottled, glossy surface is natural.
Ostrich Egg Activities:
How big a breakfast?
Fill your ostrich egg with water and measure the contents. Now measure the fluid that comes from a regular chicken egg. Comparing the two, can your students determine how many omelets could be made from your ostrich egg? Can they estimate the mass of the egg before it was emptied?
Is it accurate to say that an ostrich egg is the largest single cell in the world today?
Why is the shell of an ostrich egg so thick?
Eggs shells are made of calcium. Where do ostriches, and other birds, get the calcium to produce hard shells?
Super! Neat! Wow! Ostrich Facts!
• Ostriches cannot fly.
• Ostriches produce extremely strong leather.
• Ostriches are not an endangered species – there are at least 2 million worldwide.
• Ostriches are one of the fastest animals in the world. They can sustain a speed of 40 miles per hour (64 kph) for 30 minutes!
• Ostriches do not bury their head in the sand. They lie down and extend their neck along the ground when threatened.
• The ostrich egg is the largest bird egg in the world today, but not the largest ever. That distinction goes to the elephant bird. Its eggs were up to 90 cm in circumference, and could hold 9 liters! They’re extinct now but may have walked the earth as recently as the mid 17th century.