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Author | Everything
Compile the | Mirror
Summer beaches are always fascinating, can't wait to embrace the blue sky, the blue sea, the sand, the beautiful girl (fog)? In addition to these beautiful scenery, the seaside actually hides a secret world that is difficult to see with the naked eye. Let's narrow ourselves down to a miniature little person smaller than Arietti, a borrower, and embark on a wonderful journey into the microscopic world!
"Lively" sandy beach
Look at the beach from a distance, the vast yellow sand... Seems a bit monotonous. Don't worry, let's take out the scientist's "magic mirror" - the microscope, and take a good look, you will find the secret treasure of the beach. In addition to sand, crystalline quartz particles, this jewel-like world is home to the remains of many marine invertebrates, such as corals like branches, small fragments of various shells, and so on.
Image source: RPS
Next, let's go back to the ocean, the origin of these "treasures", and look for those "treasures" that are easy for us to miss. In fact, don't bother too much, taking a drop of water from the sea is a big world.
Exquisite "glass buckle"
Image credit: labroots
With the help of a microscope, you are likely to find these richly shaped and regular "crystal glass buckles" in the treasures of the beach. If you asked a geometrist to design jewelry, it would probably look like this. In fact, these are all single-celled algae, which use siliceous matter (mainly silica) to create a delicate protective shell (cell wall) for themselves, so it is called diatoms.
Despite their tiny size (only 10-200 microns), as the most common planktonic algae, they produce about 20% of the Earth's oxygen each year, absorb more than 6.7 billion tons of silicon, and contribute nearly half of the ocean's organic production.
Marine "marker"
Bottle-shaped foraminifera | Image source: RPS
This glass vase, which looks like a delicate craftsmanship, is not a man-made object, but a shell of foraminifera (Foraminifera), collected in the tropical waters of our country. They are less than 1 millimeter in size, about the size of a fine grain of sand. There are many small holes in the shell, from which the name "foraminifera" is derived. Their shells are rich in form, such as bottles (as shown above), spirals (below), lenses and so on.
Spiral-shaped foraminifera | Image source: Wikipedia
Although some look like "vases", they are by no means just "vases". From the Cambrian period to the present, foraminifera are almost all over the ocean, so it has become a good helper for geologists. In china's inland areas, such as Beijing, Shanxi, Hubei, and even Sichuan and Xinjiang, foraminifera have been found, which shows that these places were once the territory of wang yang. Attentive scientists have also found that when the temperature of the sea is low, the shell of the foraminifera is smaller and the pores are reduced, so it is also used as an indicator of the climate in ancient times.
Blue "Sea Elves"
Image source: Wikipedia
As night fell, such a dreamy scene suddenly appeared on the seashore, and it had a poetic name called "Blue Tears". Have you ever wondered what it is? Are they blue elves?
Let's use a microscope to unravel the mystery! The plankton, which resembles a moon in the water, are one of the main producers of the blue fluorescent sea, Noctiluca scintillans. When they are disturbed, they fluoresce through luciferase to create fluorescence to have the effect of deterring predators.
Luminous algae | Image source: Wikipedia
Luminous algae belong to the Dinoflagellata phylum , a species that often drags two " braids " ( long flagella ) .
Image credit: American Museum of Natural History
The double flagella is simply a challenge to the existence of taxonomists. Because they range from heterotrophic types that ingest nutrients from the outside world, as well as autotrophic types that can photosynthesize, and many species are mixed nutrients (both autotrophic and heterotrophic). Although it has typical eukaryote organelles (Golgi, etc.), chromosomes do not bind to histones like most eukaryotes, but are end-to-end connected to form rings, showing the characteristics of prokaryotes, so they are called mesokaryto.
A beach stroll is almost here, and it's time to head back to the resort for a seafood dinner. Let's take a look at some of the good dishes.
The teeth of the shellfish
This is a mollusk called a cap shell, whether it is delicious or not, but "super eating" is true. Opening their shells, there are actually sharp weapons hidden in their weak bodies. The image below shows the teeth of the microscope shell, which is the strongest biological material in the world ever discovered. It is as hard as steel and has a tensile strength stronger than spider silk. Originally, the teeth of the cap shell are mainly composed of echirite nanofibers (about 80%), formed by mineralization (biomineralization), which can be said to be a true "iron tooth copper tooth".
Why do you need such hard teeth? Because their favorite algae are attached to the surface of the rock, such sharp teeth can scrape the algae off like a razor. Often scraped like this, the sharp blade will be blunt, don't worry, the most important thing about the hat shell is the tooth. There are more than 100 rows of teeth on the tongue of the shellfish, which are constantly replaced like conveyor belts, but only the outermost first ten rows are used for feeding, and the damaged teeth are also replaced within 1-2 days.
Barnacles mouth
You've probably heard of one of the most expensive ingredients in the world – gooseneck barnacles.
Gooseneck barnacles | Image source: Wikipedia
Although we are not so extravagant, some ordinary barnacles are also edible. They often attach to rocks or under the hull, causing headaches for the crew. They tend to shrink into their shells, like bumps growing on rocks. Once the tide rises, they stick out their densely packed feet to feed on filtered plankton.
Barnacles filtered in the water | Image source: Wikipedia
The following picture is the vine foot and mouthpart of the barnacles under the microscope, does it feel like the head of a lobster?
The mouthpiece of the barnacles | Image credit: Igor Siwanowicz
In fact, shellfish-like shellfish are not molluscs but crustaceans closer to shrimp and crabs. Their 6 pairs of cranberries in addition to filter food also have the effect of exchanging gas, which can be said to be the lifeblood of barnacles.
Bones of sea cucumbers
Finally, the sea cucumber that everyone is more familiar with (finally something normal). Belonging to the echinoderm phylum , the protruding fleshy spines on the surface look a bit bluffy. But they're really a bit "hard-headed.". Remove a little of the skin of the sea cucumber, use sodium hypochlorite to corrode off the soft tissue, and then put it under the microscope, and you may see the picture below.
Bone slices of sea cucumber | Image source: RPS
These structures, like scattered anchors and shields, are actually the bones of sea cucumbers. Different types of sea cucumber bone pieces are also different, so they are used as an important basis for the classification of sea cucumbers.
The sea cucumbers we usually eat are their body walls, and the internal organs may be actively "discarded" by them in addition to being manually disposed of. When prey is targeted, they "scare the guts", which is actually a survival strategy of sea cucumbers - squirting offal to confuse or deter each other, and then flee. When the surrounding environment deteriorates, such as lack of oxygen, they also have evisceration. The reason why I dare to do this is because the sea cucumber has a strong regenerative ability, and after a few days to several weeks of repair, it will be a complete small sea cucumber.
What the? You don't want to eat and are afraid of cackling your teeth? In fact, whether it is the teeth of the hat shell or the bone piece of the sea cucumber, it is too small to be noticeable, so you can eat it with confidence. What the? Is there no money? Everything in the dream.
Finally, I would like to say that many things seem small but are actually not small, seemingly ordinary but also have unusual details. Often overlooked, they shine under the lens of photographers who are good at discovering beauty and scientists who are good at observation, and even have unexpected skills and roles. So, if you look closely, whether it is a summer beach or daily life, there will be more different microscopic scenery waiting for you.
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