Today, my daughter asked me why seawater is salty

:If I didn’t use Baidu, I really wouldn’t have known. . . .

Indeed, these questions that are close to common sense are difficult to answer, because what he needs to prove is the truth. . . .

That’s because the fish shed too many tears

A story makes it easier to understand, of course it has to be a science-themed story. A very long time ago, the Earth was entirely covered by oceans; there was nothing in those seas other than salt—no land, no life, just complete silence. Many years passed, and several meteorites fell to Earth. By chance, one of these small meteorites contained a few amino acid molecules or chains of ammonia-based molecules. This ancient meteorite also originated from the Big Bang. Due to certain accidental and favorable conditions in space, nitrogen, hydrogen, and oxygen atoms collided with each other, resulting in new amino acids or molecular chains. These ended up in the Earth’s oceans. In that vast, endless ocean, the amino acid chains found an environment similar to that of human body fluids. After wandering through space for countless years, these amino acids seemed to gain strength and began to move around in the oceans. Yet more time passed—perhaps hundreds of millions of years—and by chance, two of those amino acids met and combined to form a longer amino acid chain. Another few hundred million years passed, and this chain combined with yet another amino acid. Then, somehow, this chain broke apart, creating two new amino acids. Yet more time went by, and these two new amino acids encountered other amino acids as well, and thus life began. Over billions of years, single-celled organisms, trilobites, snails, sea turtles, and fish appeared in the oceans. When these animals died, their remains became bones that floated on the seabed. Gradually, due to the effects of tides, these remains accumulated together. More and more marine creatures turned into bones, which were pushed together by the waves. Without land, would there still be waves? I guess so. Under the force of gravity, the water on Earth isn’t evenly distributed, so it doesn’t form a perfect sphere. After another few billion years, there were piles of bones on the surface of the oceans. Over time, these bones dispersed under the sun’s rays, turning into soil and sand. Algae then started growing on these islands. Gradually, the islands grew larger, and algae began to grow in the soil as well. Has the child fallen asleep? Let’s continue the story. Eventually, algae evolved into different types, and other plants also appeared. The islands had dew and moisture, and marine animals began to move onto them. As different living environments emerged, various animals adapted to them. The islands continued to grow, and rain started to fall. Then humans appeared. One day, a child tried drinking rainwater. Ah, water really has no taste! In fact, many animals sweat, and their bodily fluids are salty. Saltiness is the true taste. Our animal ancestors originally lived in salty seawater, and they didn’t notice its saltiness at first. But as we gradually moved away from salty environments, our bodies still remained adapted to salty fluids. When we stopped living in the sea and moved to land, we thought we could adapt to drinking rainwater. But after some time, we realized that water still had no taste. One day, when we tried drinking seawater again, we found that it wasn’t suitable for us, who came from the sea. Seawater is still salty. I think this story is now complete enough. For example, children who grew up in rural areas usually sleep on kang beds. Those who have slept on kang beds don’t notice anything wrong with it. But one day, when they go to the city and sleep on beds, they realize that beds are also fine for sleeping. Then, when they return to the countryside and sleep on kang beds again, they notice that there’s a certain smell. This smell is similar to what happens when humans and other animals return to the sea after billions of years—after all, it’s their birthplace. By comparing, we can see that the sea does have a taste. It’s like the saying “Viewed from different angles, mountains appear as ridges or peaks; the truth lies not in the mountain itself, but in the perspective from which we look at it.” I think this story is now clear enough, and it should help calm down the naughty child.

Simply put, it’s the difference in sensory adaptation and environmental changes that makes us aware of the salty taste of the ocean. This difference arises mainly from the contrast between rainwater formed from water vapor and saltwater. More technically, evaporation and condensation create two very different water environments; when we adapt to one of these environments and are then suddenly exposed to another, the difference becomes noticeable to our senses. That’s probably the explanation.

Your brain isn’t useless – it’s amazing.

This post was last edited by Qingchengjun on 2018-8-28 at 14:59. It’s far too inefficient to use animal bones to create mountain ranges on land. As the Earth’s crust moves, the continental plates are squeezed and pulled, causing some areas to bulge while others sink; this is how landscapes such as mountains, landmasses, basins, and oceans are formed. The variability in crustal movements means that marine fossils can be found in mountains. As for the salt in seawater, its solubility allows it to be carried into the ocean by running water, where it accumulates. The difference in volatility between water and salts leads to water vaporization, which, along with atmospheric currents, results in rainfall patterns that vary across the globe. The low temperatures of glaciers promote the liquefaction of water vapor, giving rise to regional climate phenomena throughout the spring and summer seasons. The general trend is the accumulation of soluble salts in the oceans, while terrestrial water sources originate from the condensation of the atmosphere and have low salt content. Theoretically, the Earth’s surface can be regarded as a distillation tower, with things like glaciers in Tibet acting as the uppermost trays, where water content is high and salt content is low; the ocean, on the other hand, represents the bottom of the tower where salts are concentrated. The presence of salt mines or partial saline water along the route constitutes partial contamination of the tower equipment