I found the semi propositional essay, and I found the semi propositional essay about 500 words

The unifying power of ants.

I like ants, not only for their hard-working and simple character, but also for their spirit of helping each other and forging ahead in times of crisis.

I remember one time, a few ants were hurrying on the wall. I got up in the moment, poured water from my teacup, and threw it at the ants, who were frightened and ran away. I flooded them with water, and they were all covered in droplets of different sizes.

Although the tenacious little ants are trapped in the water, they still do not give up the opportunity to escape. They spread their calves thinner than a needle and crawled desperately to the dry place, but it was too late, and the bean-sized droplets stuck to them like glue, making it difficult for them to walk. At this juncture, I saw them in a circle, hand in hand, fighting bravely, and finally broke out of the encirclement, exhausted, lying back to back, encouraging each other.

After a while, the long queue was up again.

Their team walked in the direction of the cake crumbs that the rats had eaten, and then, the cake crumbs the size of broad beans were gone, and I moved the cake crumbs to another place, and the ants were not to be outdone, and they immediately found food. At this moment, a swarm of ants came over, and the cake crumbs disappeared from my eyes immediately.

I looked at the group of ants and sighed, it is true that ants with the size of rice grains are sometimes stronger than some people. Ginseng.

I discovered the secret of the ants.

Ants, I believe everyone is familiar with them. So who can really understand ants? Why don't ants get lost?

With this question in mind, I consulted some books. The book says that after the ants depart from the anthill and arrive at their destination, they will leave some smell along the way and return to the anthill. Touch each other with your antennae to notify the other ants.

Scientists have conducted an experiment on this issue. Scientists first identified an ant and vigorously wiped it clean along the way to its destination. When the ant returned, it suddenly stopped where the smell had been wiped off.

I was looking for something while going around in circles. Thus it is concluded that ants rely on smell to discern the direction.

To confirm this conclusion, I did an experiment. I first prepared a small branch of about 10 centimeters, and put a bait at one end of the branch - a small candy. I put this device near an anthill.

After a while, an ant came out to explore the way. After I led him to the stick, he reached the place where the candy was, as if he were sniffing and sniffing. I took the opportunity to cut off the broken part of the stick by one centimeter.

When the ant returned, it turned left and right in the place where it was intercepted, but it couldn't find its way home.

After a while, I repeated the above test again, and the ants still haven't found their way home.

Through these two experiments, I finally learned the secret of why ants don't get lost. It turns out that ants discern directions based on smell.

"Discover why swallows fly south".

When spring came, I found a pair of swallows building a nest under the eaves in front of my house. I wondered, why can't I see swallows in winter? Is it because they are afraid of the cold and go to the warm south to spend the winter?

So, I went to the book "100,000 Whys" to help me answer my questions.

It turns out that the swallow is a migratory bird. In the autumn before winter comes, they make their annual long journey—flying in pairs from north to south, where they enjoy the warm sunshine and humid weather, leaving the frost and bitter winds of winter to, grouses, and ptarmigans, which never fly south for the winter. On the surface, it is the cold of the winter in the north that makes the swallows leave their hometowns and go to the south to spend the winter, and then return to their hometowns from the south to have children and live and work in peace and contentment.

Is that really the case? Not really. It turns out that swallows feed on insects, and they have always been accustomed to preying on flying insects in the air, rather than scavenging for insect food in tree crevices and crevices.

However, in the northern winter, there are no flying insects for swallows to hunt. The lack of food makes the swallows have to make a great migration from autumn to spring every year in order to get a broader living space. Swallows have become "nomads" in the bird family.

After reading the book, I finally knew why the swallows flew south.

There are many interesting phenomena in life, but those who do not like to observe carefully will not find them, and those who do not like to learn will never acquire these knowledge. We must polish our eyes and be people with a heart for life.