"Lice" have coexisted with us for tens of millions of years, so why haven't we seen them in recent years?

When talking about lice, everyone may feel their scalp tingling. Such a small thing can cause a lot of trouble to humans.

Its history is longer than that of humans, and it has coexisted with humans for thousands or even tens of thousands of years. Why has it not been seen in recent years?

Lice from millions of years ago

In 2011, the British Daily Mail published a paper stating that scientists extracted genes from 69 species of lice and found that lice had existed as early as the era of dinosaur rule 65 million years ago.

These lice lived in the dinosaurs' hair, making the dinosaurs' tempers quite bad.

The dinosaurs could only use fighting to relieve the itching on their bodies.

After the planet hit the earth, the lice survived and parasitized some hairy animals and began to evolve.

During this period, bird hair is the best place for lice to live.

But birds are not terrestrial creatures after all, and their living habits make it difficult for lice to adapt.

About 30 million years ago, primates appeared, and lice naturally came to primates.

Later, chimpanzees, close relatives and ancestors of humans, emerged among primates, and lice also infected chimpanzees.

About 4 to 6 million years ago, humans differentiated and became an independent species.

As the lifestyles of humans and chimpanzees have diverged, the lice on their bodies have also evolved in different directions.

As species became more diverse, different races emerged among the differentiated humans.

For example, early Homo habilis, Homo erectus, Homo sapiens, etc. lived in different environments, and their body characteristics and lifestyles also differed.

The lice on their bodies are also constantly evolving.

Homo sapiens lived about 200,000 to 40,000 years ago, after which "modern humans" appeared.

After humans evolved into "modern humans", as advanced primates, there are no other branches. Theoretically speaking, there should only be one type of lice on humans today.

But this is not the case. American scientists have discovered that there are two main types of lice on humans today, and these two types of lice began to differentiate about 1.2 million years ago.

In other words, only one species of lice is native to "modern humans", while the other species is imported!

what does that mean?

Scientists believe that the presence of two species of lice on humans proves that the ancestors of "modern humans" had close contact with Homo sapiens about 40,000 years ago.

Because lice can only be spread through fighting, wearing the same clothes, intimate behavior, etc.

Of course, more evidence is needed to prove the truth of this statement.

If this statement is true, it will be a subversive existence in the history of human evolution.

Many scientists also believe that American scientists must have accurate data on the number of two types of lice on humans, and the sample estimation method cannot completely convince people.

In fact, no matter which statement is true, it cannot change the fact that lice are gradually disappearing from our bodies.

Especially after entering the 21st century, traces of lice are rarely found in human hair. A "troublesome creature" that has accompanied humans for tens of millions of years seems to have disappeared in just a few decades, which makes people puzzled and worried that it has a big trick up its sleeve.

Environmental hygiene

When talking about the reason why lice disappear, we have to talk about the place that lice like most: hair.

But not all hair is suitable for lice to live.

For lice, firstly, they cannot stand the sight of water, and secondly, they cannot smell fragrance. To them, fragrance is like "poison gas".

Only dirty, smelly hair is an ideal place for lice to settle.

Especially for those who don’t wash their hair for ten days or half a month, lice love it very much.

In the first half of the last century, most people in our country were busy working to make a living and had no spare time to take care of their personal hygiene.

As a result, everyone's hair became an excellent habitat for lice. These lice lurked in people's scalps and reproduced at will. Therefore, when people at that time opened their scalps, they could catch a handful of lice.

As for tools for cleaning the body such as shampoo and soap, only rich people use them.

Most poor people just rinse it with clean water.

Lice will become more sticky in human hair, and the longer they stay, the harder it is to wash away.

If you rinse your hair frequently, you can wash away the lice on your scalp, and even without shampoo, it will be difficult for lice to infest your hair.

But since people don't use cleaning tools when taking a bath and don't take a bath frequently, it's understandable that they get lice.

After the founding of the People's Republic of China, the country developed steadily. People were busy in the fields during weekdays and had free time at night, so they began to pay attention to their hygiene. As people's living standards gradually improved, they began to use cleaning tools when taking a bath, such as rubbing their skin with a bath towel.

After the reform and opening up, people's living standards have improved rapidly, and they have paid more attention to their personal appearance. Various foreign cleaning products have also flowed into the domestic market and are highly sought after by everyone.

Nowadays, it is very cheap for people to take a hot bath, basically one hot bath a day.

How did you let the lice parasitize? I'm afraid they would be washed away by the hot water before they could even stand firmly.

It would be fine if it was just to take a bath diligently, the key is the wide variety of cleaning tools. After a hot bath, the fragrance is everywhere, and some girls even spray some perfume on their bodies.

Such a parasitic environment makes lice cry out in dismay and leave humans with curses.

Secondary causes

A major reason is that people are cleaner, but a secondary reason is that they give lice less opportunity to spread.

In that poor era, a piece of clothing could be said to be "passed down for three generations."

Just spread it if you want, the key is that it hasn’t been washed for two or three months.

They would mend and sew the clothes over and over again, and only after they had passed them through everyone in the house would they be willing to buy a new one.

If you keep changing clothes like this, even if you don't have lice, you will still be infected by others.

After living conditions improved, everyone wore their own clothes. They threw the clothes they had worn for a day into the washing machine, took them out and put them in the dryer for ultraviolet disinfection.

How could the lice living on the clothes endure such "torture"? They just ran away.

How to prevent and control lice?

Of course, for some people with special physical conditions, they will still have lice on their bodies even if they take a shower every day.

Don't worry. Science is so advanced nowadays. Just go to the hospital and ask the doctor to prescribe some chemical agents. Spray them twice a day and the parasitic lice will soon die on the spot.

If you don't want to go to the hospital, just shave your head, cover your scalp with a hot and wet towel every day, and apply alcohol afterwards.

If you are worried about lice or parasites in your sheets, just soak the sheets in boiling water for a while, and all the lice and insect eggs will be killed.

For clothes that are not resistant to water and heat, you can use dry cleaning to deal with the lice that are parasitic on them, and then spray them with a pure natural insect repellent that is harmless to the human body.

It is worth noting that lice have not completely disappeared from our lives. If you are not clean, it won’t be long before the lice will come back again.

Today, there are still some remote mountainous areas in our country where people live in backward conditions and some people still suffer from lice.

Fortunately, our country has been vigorously supporting remote mountainous areas every year. I believe that it is just around the corner for our country to achieve “lice-free for all”.

What do you think about this? Welcome to leave a message in the comment area. Follow CHN Jiuxiang Technology, and through popular science, you will find that there are too many wonderful things in this world.