The color of human eyes is one of the most expressive and striking features of human appearance. It is determined by a combination of genetic factors and various biological processes. In this review, we will talk about why and why different people have green or blue eyes, and also discuss the role of anatomical features and processes that play in this manifestation.
Biology
Interesting facts, knowledge and news related to the science of Biology are collected here.
There is an opinion that the largest living cell is the ostrich egg. An African ostrich egg can reach a height of more than 17 cm and weigh about 1.5 kg, but this does not make the ostrich egg the largest cell known in nature. For example, a giant squid nerve cell can reach 12 meters in length. In the plant world, the cell of Caulerpa (seaweed) has many nuclei, and it can grow up to 3 m in length. If we nevertheless consider the egg of the largest bird, then, most likely, the egg of Epyornis (an elephant bird reaching a height of 5 m) would be one of the largest. Unfortunately, this species is considered extinct (destroyed by humans in the 17th-18th centuries), although eggs of this legendary bird are still found.
Each of us has probably seen at least two types of chicken eggs in the market or supermarket - coffee (beige or brown) or white. The color of the eggs depends on the breed of chicken. The shell of a brown egg is colored already at the last stage of formation before laying. As a rule, only the top layer of the shell is painted, and if you rub it with a vinegar solution, you can erase the pigment to white. So, after all, why are chicken eggs different colors? Let's figure it out.
Did you know that the product of sperm whale burps is used in perfumery? Ambergris or Ambergris is a waxy substance that is formed in the stomach of the sperm whale. This is a rare substance that is obtained as a result of irritation of the gastric mucosa by the horny remains of cephalopods and only in males! Ambergris: sperm whale burps are a valuable product and very scarce. It is bought by perfume manufacturers for very good money. In perfumery, Ambergris is used as an odor fixative.
They say that a cat sees better than a person. Especially in the dark. Cats need this, first of all, for hunting. After all, all cats are predators. But at night they see really well! The fact remains a fact. But why? It is better to turn to science with this question. And yet, are cats really blind? The unique vision of cats is based on the following scientific data.
It turns out that the amount of hair on the heads of blondes, brunettes and redheads is different. The hairiest ones are blondes. There are from 120 to 140 thousand hairs on their heads. In second place are brunettes and brown-haired people. Their hair count varies between 100-110 thousand hairs. Redheads have the least amount of hair – only 80-90 thousand. On average, a person loses 50-100 hairs in one day, and more than 1 million hairs fall out in a lifetime. If you are interested, then read further: Interesting facts about our hair.
Fish gather in schools, birds gather in flocks. But more amazing things can be seen in the sky when birds create three-dimensional pictures and images that are constantly changing dynamically. The dance of starlings is a phenomenon in nature when a flock paints pictures in the sky. And it’s called Murmuration! A large flock of birds (starlings, crows, jackdaws) creates a black cloud of variable density that changes shape. This is truly a grandiose spectacle. Nature, always possessing miracles and secrets, occasionally provides us with amazing performances that leave us in incredible delight.
Murmuration is one such phenomenon where a flock of birds creates real art in the skies. Let's dive into this wonderful world and try to understand it.
Large mosquitoes and malaria... Let's try to sort out the myths and reality. When we talk about mosquitoes, images of summer nights immediately come to mind, when these little blood-sucking insects turn into a real nightmare. Itching, biting and unhappiness - this is how we can characterize our interactions with ordinary mosquitoes. However, there is another legend in the world of mosquitoes - large mosquitoes that are said to carry malaria and are a real threat to human health. So, is it true that large mosquitoes are malarial? Let's try to understand this myth and find out how true it is.