Strange birds: Although small, laying eggs is one of the largest in the world

Kiwi birds can produce weight eggs that make up 25% of the body - a ratio that is too large for other birds. Why so?

The Vietnamese proverb has the phrase: "Cheating at the door" - saying that pregnancy and childbirth are not merely painful and hard, the mother also faces many risks. This statement is not only true for humans but many other animals on Earth.

In it, the most poignant is probably the mother of the Kiwi bird, the symbol of New Zealand bird. Because the eggs of this species can account for a quarter of the female bird's weight in the last months of pregnancy.

That's right, you're not mistaken, it's a quarter. To convert, it is like a mother who has to carry a 15kg pregnancy in the last month. And if compared to the bird world, it is a huge proportion

X-ray images showed that on the volume correlation, the egg occupies one third of the mother's body cavity.

Kiwi is a common name for many native New Zealand bird species, located in a group of birds running along with some ostrich species today. However, far from my cousins, the size of the Kiwi is very small. They are only about 50cm tall, weigh 1kg, which means only a small chicken. Meanwhile, unusual ostrich branches range in size from 1.2 to 3m.

That's small, but maybe because I don't want to have to be inferior to my next life, instead of giving birth to small eggs to suit my size, my mother Kiwi is often pregnant and gives birth to "terrible ". Its eggs weigh between 0.15 - 0.25kg.

The kiwi eggs are as big as the other birds' eggs while the kiwi are very small.

This strange feature has challenged scientists for a very long time. Because from the point of view of evolution, the birth of laying an egg so big does not know what benefit it will bring? Is it necessary to create a profound meaning when letting this little bird give birth so hard?

Previous researchers also believed the same thing, until the Kiwi genetic map was published. Realizing that Kiwi and many ostriches have the same ancestors, scientists have argued that the big egg probably doesn't benefit at all, it's just an evolutionary error.

Kiwi Bird.

They hypothesized that the ancestors of today's running birds - including the Kiwi ancestors, were all enormous, none of which were inferior to any other. Later, the Kiwi became smaller, while their eggs were the same size.

Obviously, this brings no annoyance to the mother bird. They move harder, easily become prey to predators and are exhausted at birth. In addition, Kiwi only gives birth to 2 or 3 litters a year, one egg per litter, a modest number.

However, many researchers believe that this characteristic also offers certain advantages for the species. Big eggs are thick and hard shells, young offspring will not be too weak, can even run away from predators.

Interestingly, right?