Lead
One of the oldest creatures on earth is the sea lily, its fossils can be traced back to the early Cambrian period, is an ancient echinoderm, has appeared on the earth a long time ago, and is also the toad in the ancient literature of the continent mentioned in the "toad is born in the mud, and man is the first to be", which actually refers to the sea lily.
The body structure of the sea lily is divided into three parts: stem, calyx and wrist, which resembles a plant and is a parasitic plant, which was considered a plant in water in ancient times, but in fact it is an animal in water.
The sea lily lives in the water, attaches to stones or rocks, and its body can be stretched and contracted freely, so as to adapt to changes in the living environment.
Sea lilies were one of the most common paleontological animals and a major creature at the time, when the bottom of the sea was almost all over the place.
The appearance of sea lilies has attracted great attention and also triggered the thinking about the origin of life, is there any other life on earth?
How likely is life in the universe?
1. The peak era of prehistory.
As early as the Cambrian period, sea lilies appeared on the earth, arguably one of the oldest organisms on the earth, and its appearance has also made paleontologists very interested in the origin of living things and the diversity of life.
The Cambrian period is the origin of life, when the organisms on the earth were very single, mainly some primitive fungi, algae and bacteria and other microorganisms, with the continuous evolution of the earth's environment, life gradually developed and adapted to the living environment.
The sea lily is a product of this period, and its appearance also marks the beginning of the development of biological diversity.
In the Cambrian period, the earth's organisms were dominated by the ocean, and it was also the earliest life on the earth, with the evolution of the earth's environment and the evolution of organisms, organisms gradually separated from the marine environment, and plants began to appear on land, and then some animals appeared on land.
Sea lily is an animal that lives in the ocean, its stem can be stretched freely, can be freely opened or contracted, parasitic on stones or rocks, as a parasite in the ocean, its nutrition mainly comes from passive absorption, but its nutrition can be maintained for a long time, can meet its ability to survive in the absence of foraging.
The body of the sea lily is shaped much like a plant and can be divided into three parts, which are the stem, the calyx, and the wrist:
The stem is the main part of the sea lily, and it is also its body, which can be expanded and contracted, and can be opened or contracted to adapt to changes in the living environment;
The calyx is the topmost part of the stem, with an umbrella-like shape that protects the stem and slows down the impact of water flow on the stem;
The wrist is something like a tentacle on the stem that can be used to find food.
The nutrition of the sea lily mainly comes from its wrist, which can be opened to find food, and when it finds food, it will adsorb food to it, and then use its wrist to bring food to its mouth, and after eating, it will continue to look for food, and so on.
Sea lilies are usually small, with stems about a few centimeters in length, but during the Carboniferous period, sea lilies reached their peak and their bodies changed dramatically.
In the Carboniferous period, the number of sea lilies was very large, and the bottom of the sea at that time was almost all over the sea lily, and some sea lily stems were even more than 60 centimeters, and they formed a vast community on the bottom of the sea, forming a dense sea lily forest on the bottom of the sea.
In the Carboniferous period, the oxygen content was very high, reaching 35%~40%, which is 2.5 times the current oxygen content, which also had a huge impact on the organisms at that time, and the body size of the organisms also changed greatly.
In addition to sea lilies, insects such as dragonflies soared through the air, and land creatures such as lake dragons lived on land, and there were many types of creatures, so it can be said that the period of the greatest biodiversity was the most abundant.
The number of sea lilies is very large, but on land, there are some giant insects, such as the giant dragonfly, because the oxygen content at that time was very high, so the size of the insect is also very huge, just like the dragonfly now, nearly the size of a hand, the wings spread out 45 cm, and the wings of the giant vein dragonfly spread out 75 cm, which can be said to be several times that of the dragonfly now.
Not only the wings are large, but the body is also very long, with a body length of 45 cm, which can be said to be the giant of dragonflies now, and it is the "nouveau riche" among dragonflies.
The number of giant dragonflies was very large, almost all of them were in the air at that time, and its number was also very large, which can be said to be the most common insect in the air at that time.
Second, the lake dragon.
In addition to the creatures that live in the ocean, there are also some creatures on land, including the lake dragon, which is an early terrestrial large four-legged carnivore, which is very large, can reach 1.5 meters in length, and is a very ferocious animal.
There are many species of lake dragons, some lake dragons are also very large, can reach 2.5 meters, is a very giant animal, it is one of the ancestors of reptiles today, covered with scales, very popular at that time, the number is also very large.
In addition to marine and terrestrial organisms, there are also some organisms that can live on land and sea amphibians, such as the coral snail, which mainly lives on coral reefs on the bottom of the sea, feeds on corals, and is a mollusk in the water, which was also very popular at that time.
It can be seen in many places, but with the continuous change of the earth's environment, some creatures have gradually disappeared, such as the lake dragon, which was very popular in the Carboniferous period, but with the passage of time, the lake dragon gradually disappeared.
3. Climatic conditions of the Carboniferous.
The climatic conditions of the Carboniferous period had a great impact on the evolution of the body size of organisms, and climate change will change the size of organisms, and the size of organisms will also change according to the different living environments.
In the Carboniferous period, the oxygen content was very high, which provided the possibility for the gigantic insects, such as the giant dragonfly, which was an insect that lived in the air at that time, because the oxygen content was very high, so its wings could easily bear its weight, and the wings grew larger and larger, reaching 75 centimeters, which was several times that of the dragonfly now.
But as time goes by, the oxygen content is getting less and less, the gigantic insects have become history, and the current insects are not as big as before, such as the dragonfly, its wings are only the size of a hand, which is several times that of the giant dragonfly, but the giant dragonfly has gradually disappeared.
The number of giant dragonflies is very large, almost able to cover the entire sky, but with the continuous change of the environment, some creatures have gradually been eliminated, the giant dragonfly is one of them, and the insects are not as big as before, and the number has become scarce.
The prosperity and extinction of organisms is the norm in the evolution of organisms on earth, and the emergence and disappearance of species are the result of organisms adapting to the environment, and they are also inevitable phenomena in the process of evolution.
epilogue
Sea lily is a kind of diversity produced by organisms in the process of adapting to the environment, and its appearance also allows people to see the organisms of different Cambrian periods on the earth, and also makes people reflect on the evolution process of organisms and the diversity of life.
The biological peaks of the Carboniferous period show the diversity of life and the complexity of ecosystems, which provides valuable references and enlightenment for us to understand the history of life on Earth.