Share today: Sea Lily
Comparison of pictures of sea lilies and pictures of art books (left: sea lily fossils Right: pictures in textbooks)
Recently, when Wu Yefan, a second-grade primary school student in Shanghai, looked through the art textbook, she found that a photo cited in the textbook, "Leaves" Modern Pottery Works, was very similar to the sea lily fossil she saw in the Museum of Natural History. After comparison with the museum, the "modern leaves" on the Shanghai version of the second-grade art textbook are indeed the paleontological "sea lilies" hundreds of millions of years ago. It was called directly by countless netizens: too powerful, the afterlife is terrible!
Friends, when it comes to sea lilies, do you think it is a plant or an animal? Does it live in the ocean or on land? Today's "Subject Knowledge" column gives you the knowledge of popular sea lilies and beautiful and peculiar marine life.
echinoderm
Sea lily is not a flower, sea lily is a kind of echinoderm first seen in the Early Cambrian, with multiple brachiopods, the body is flower-like, the surface has a calcareous shell, because it looks like a plant, people have given it the name of the plant, the body of the sea lily has a plant-like handle, and the pinnate thing on the upper end of the handle is the tentacles of the sea lily, these tentacles are like the leaves of ferns, thus confusing people into thinking that the sea lily is a plant.
Sea lilies are not marine plants, but a very old invertebrate, this animal can not walk, all its life on the seabed, but also by the attack of fish, mainly by the tentacle-like wrist to prey on plankton, from the deep sea to the shallow sea are distributed, prefer clear water. Hundreds of millions of years ago, they were everywhere in the ocean.
Historical distribution
During the Paleozoic Carboniferous Period, the number of sea lilies was extremely large and varied, and could be classified under several categories under the "General Order of Sea Lilies". They form a large, grassy-like cover along the seabed with mosses and brachiopods, leaving many fossils. Later, due to the "Permian and Triassic extinction events", 90% of marine species went extinct, and sea lilies quickly withdrew from the historical stage.
When the living species of sea lilies were first rediscovered, they were in deep waters, so it was initially thought that they could only survive in the deep sea. It was later discovered that it could be found in shallow or deep seas, tropical coral reefs or high latitudes.
Main species
Sea lilies are the oldest species of echinoderms, with more than 620 species of sea lilies worldwide. It is often divided into two categories: sessile sea lilies and sessile sea lilies. The stalked sea lily is fixed to the deep seabed with a long handle, where there is no wind and waves, and no solid solids are required. There is a flower tray on the stalk that contains all its internal organs. The mouth and anus of the sea lily are open upwards, unlike other echinoderms. Its thin wrist protrudes from the flower holder, and the wrist is composed of branches and can move, with smaller branches on the side, like feathers. The wrists are like windmills facing the current, catching small animals in the seawater for food.
Habits of life
Sea lily has been rooted in the bottom of the sea all her life and cannot walk. They are often ravaged by schools of fish, some are bitten off "stems", some are eaten "flowers", and they end up with tragic endings. This sessile sea lily, colorful, leisurely wandering, drifting around, is known as the "fairy of the sea". Biologists gave it another name— "Feather Star." The "feather star" contains toxins, and many fish dare not touch it. Because he can move freely and his body can change color with the environment, he has become a Wang clan in the sea lily family.
Sea lily fossils
Sea lilies have a strong regenerative ability, and can regenerate if they lose part of their wrists or calyxes. During regeneration, the internal nervous system plays a major control role. Somatic cells remove damaged tissue and bring nutrients with them, so they play an important role in regeneration. After the death of the sea lily, the calcium-containing "stem" and "calyx" were preserved as fossils. If the sea is disturbed, these stems and calyxes are scattered around, most of them have lost the beautiful posture of lilies; only in a particularly calm seabed, after death, can complete fossils be preserved, because this environment is more demanding, so such fossils are very precious, not only for the geological and historical period of paleoenvironmental research to provide important evidence, but also gradually become the treasures of fossil collectors, and even as handicrafts.
The ocean is the origin of life, which has given birth to countless lives, and the seabed is also full of vitality and beauty because of the existence of these life. The ocean is big, the mystery is endless, the marine life, the variety of things. Let's take a look at the various magical creatures that live in the ocean!
The bulb sea squirt is a colonial sea squirt, and from the transparent coat you can see the yellow and white organs inside, which looks like a light bulb, and the name of the bulb sea squirt comes from this. They are mostly found along the Norwegian coast, but they are widely distributed in the Atlantic, North Sea, English Channel and Mediterranean Sea. They are often loosely packed together, their shape is cylindrical, 4 cm long, and they grow violently in the harsh winter and are revived in the summer.
The Christmas tree worm is small and is a type of tube worm. These fascinating corals come in many colors, yellow, orange, blue, and white, and are widely distributed in tropical oceans around the world. The worm's colored spiral is actually a high-density breathing structure, it does not have auxiliary limbs dedicated to movement and swimming, and cannot swim outside the tube. They have two beautiful crowns that make them look like Christmas trees, hence the name. These crowns are actually their mouths, very sensitive, even the shadow of them will react immediately. Tubes are their homes.
Bubble corals are beautiful, and many bubbles will appear in immovable water, and the name bubble coral comes from this. They need light to expand and expand, and when they open during the day, they look a lot like bubbles, pearls, or grapes. When deflated, you can see that they have a hard skeleton. These corals are very fragile and crumbling when touched, so be sure to be careful with their tentacles when handling and collecting them. Bubble corals are mainly distributed in the Red Sea, Indian Ocean and Pacific Ocean.
The large flower-brain coral has an oval heavy frame with a conical chassis. Also known as stacked-brain corals or pit corals, they are large hydra-bodied polyps. This beautiful coral comes in red, yellow, brown, green and blue. They are shaped like the number 8 or a clock. At night, you will spit out tentacles in your mouth to protect yourself. They are about 80 mm long and have 2 or 3 mouths. Survives through photosynthesis and does not require feeding. Red requires less light than green. It's easy to collect such corals because they like to stick to reefs, shells, and dead corals.
Cup corals are beautiful corals from the deep sea. They are not species that grow on the reef, but live on zooplankton. At night, they protrude their translucent tentacles. Cup corals are widely known as the flower of the ocean and are also known for their vivid colors and shapes. Their most common shapes are cups and plates.
Leather mushroom corals belong to the soft coral family, and other common names are green mushroom coral, umbrella coral, and elephant ear leather coral. Like other corals, they come in many colors, including brown, cream, and deep red. This beautiful mushroom coral looks like folded leather, and at night and when eating in the water, they reveal peduncle-like tentacles. They are colonies of marine animals, and marine life provides them with nutrients.
Finger corals are good-looking corals that look like fingers, and have many names, such as finger leather coral, Noby finger leather coral, devil's hand coral, kale leather coral, and so on. They come in a variety of colors, such as brown, brown, yellow, green, pink, and gray. They originally belonged to the Indian and Pacific Oceans. These unique corals, 1-2 inches in size, draw nutrients from an algae that resides inside the coral and survives through photosynthesis. They also draw nutrients from tiny plankton. Their appearance depends mainly on the strength of the currents.
Who would believe that these beautiful bright feathers are a worm called a feather duster worm? The feather duster worm resembles an old-fashioned feather duster, with all but its head in a tube of sand deposited. The tubes on the worm's head have two crowns and are the organs that feed it breathes and eats. These things hidden in the tube are small, but sensitive and can detect danger. Beautiful red, orange or brown sponges roaming around the worms also add a touch of beauty to them.
These mushrooms are like the paint in the painter's paint plate scattered across the ocean, they have fascinating colors, red, orange, purple and green. The red tiger ear mushroom is the rarest and most precious. Tiger ear mushrooms of different colors require different care. The green tiger ear mushroom is a type of mushroom coral with spots on its surface, which is a vibrant green color. The Atlantic and Caribbean green tiger ear mushrooms are classified as Florida tiger ear mushrooms, and the Pacific green tiger ear mushrooms are classified as Yuma tiger ear mushrooms. The green tiger ear mushroom is a hard mushroom that slowly hardens. The orange tiger ear mushroom is relatively large. Yuma Tiger Ear Mushroom is distributed in the Pacific and Indian Oceans, while Florida Tiger Ear Mushroom is distributed in the Caribbean. The red tiger ear mushroom is more exotic, more precious, beautiful and gorgeous. They are sensitive and not as hard as other species of coral. Care must be taken when handling them, as small travettes of the red tiger's ear mushroom can also lead to bacterial infections.
The lilac hydra body, also known as the gloved hydra body, has eight tentacles. These stunning hydras are found in the Indian and Pacific Oceans and are available in brown, red, pink, white and green. The small ones are clove hydras, while the large ones are usually used as gloves for hydras. Regardless of size, they have eight tentacles. They depend on iodine, bran shrimp shrimp, planktonic microorganisms and trace elements, usually in swarms and require moderate amounts of light. They can develop and grow rapidly on coral reefs and rocks.
The oceans cover about two-thirds of the Earth's surface and are the foundation of life. The ocean has bred life, fed a large number of marine life, and contains unlimited energy. However, the ocean also needs our care and care, according to CCTV news, about 10 million tons of plastic waste flows into the ocean every year; last year, more than 1.5 billion masks flowed into the ocean, it takes more than 400 years to decompose; about 6 million tons of oil enter the sea through various channels every year...
It is urgent to protect biodiversity and protect the environment! In addition to sharing beautiful marine life with you, the discipline network also has a wealth of biodiversity and biological evolution and other learning materials, if you need, you can visit the discipline network to view.