Males attempt to drive away all other males. Battles between males for females usually last just a few minutes, but can be fatal by competing males slamming their heads into each other. Males alternate wing beats until attracting a female. The two graze in synchronization, then the male excitedly flaps alternate wings while poking the ground with his bill. He will then violently flap his wings to symbolically create a nest in the dirt.
While the female runs in circles around him with lowered wings, he winds his head in spiral motions. She then drops to the ground for him to mount her. An alpha ostrich male constructs a large communal nest in the ground for his hens to lay their eggs.
There can be more than 20 eggs in the nest, but usually only a couple eggs actually hatch as they are preyed upon by predators. Each female can determine her own eggs. Ostrich eggs are the largest of any bird species, 10 times larger than a chicken egg. Incubation of ostrich eggs takes about 6 weeks. They are incubated by the dominant female during the day, and by the male at night. Using the coloration difference of the two sexes, they attempt to prevent predators from detecting the nest.
From a distance, it just looks like the ostrich has buried its head in the sand, because only the body is visible. Some ostrich eggs are lost to hyenas, jackals, and even Egyptian vultures, which break open eggs by dropping stones on them. Native to Africa, ostriches are found in savanna and desert regions , were they graze among giraffes, zebras, wildebeest, and gazelles.
Ostriches are omnivores, and they eat whatever is available in their habitat at that time of the year. They mostly eat plants, especially roots, leaves, and seeds, but they also munch on insects, snakes, lizards, or rodents that come within reach. When an ostrich eats, food is collected in the crop at the top of the throat until there is a large enough lump to slide down the throat.
They have tough intestines that are 46 feet 14 meters long—if you stretched them out—in order to absorb as many nutrients as possible. These big birds also swallow sand, pebbles, and small stones that help grind up food in the gizzard. Ostriches do not need to drink water, since they get what they need from the plants they eat, although they drink if they come to a water hole.
They also have a special way of raising their body temperature on hot days to reduce water loss. Ostriches at zoos are fed special bird pellets containing vitamins and minerals, along with browse and vegetables like carrots and broccoli.
During courtship, the black-and-white male uses his dramatic coloring to attract the light brown female. He then gets up and moves toward the female, holding his wings out and stamping as he goes to impress her. If she approves, she mates with him. The dominant or "alpha" hen mates with the territorial male, and they share the tasks of incubating the eggs and caring for the chicks. The main hen puts her eggs in the center of the nest to make sure they have the best chance of hatching, but many of the other eggs may also be incubated.
Ostrich eggs are famous for their size, averaging 6 inches 15 centimeters in length, 5 inches 13 centimeters across, and weighing about 3 pounds 1, grams. An ostrich hen lays 7 to 10 eggs at a time, but her large body can easily cover dozens more. Meet the people trying to help. Animals Whales eat three times more than previously thought. Environment Planet Possible India bets its energy future on solar—in ways both small and big.
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Travel The last artists crafting a Thai royal treasure. Subscriber Exclusive Content. Nipples of male mammals, for example, probably never had any function.
They persist, however, due to the genetic blueprint shared by all human foetuses—and because there is no particular harm in them hanging around. The important thing to realise is that evolution is still happening right now.
What we see is often a stage in the disappearance of an old function, or the honing of a new one.
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