Why was the trilobite the first animal to dominate the earth?
The history of the earth has been 4.6 billion years, and the first great development of the animal kingdom was in the Cambrian period 600 million years ago, and the most animals in the Cambrian period were trilobites, accounting for about 60% of the total number of fossils preserved, followed by brachiopods accounting for about 30%, and other arthropods, worms and ancient cups accounted for about 10%. Therefore, we call the Cambrian "Age of Trilobites", and trilobites became the first animals to dominate the earth. After the Cambrian, the animal kingdom continued to undergo several major developments, and the great development in the Cambrian period was the "first spring thunder".
Trilobites live a diet that floats on the surface of seawater, swims in different depths, and crawls on the bottom of the sea. Because the lifestyle is diverse, it can be found in different depths of sea water and various sea areas, so its geographical distribution is extremely extensive. They can be found from the Daxing'an Ridge in Heilongjiang Province on the mainland to Hainan Island in Guangdong Province, from the Pamir Plateau in Xinjiang to the coastal areas of Jiangsu and Zhejiang, and in the Everest region of the Himalayas. It is one of the many types of fossils on the continent. At the same time, the continent is also one of the countries with the largest production of trilobites in the world.
Many of the benthic or semi-swimming orchids produced in many Asian countries are identical to those on the continent, proving that during the Paleozoic era, Asian regions were linked. Interestingly, Oceania and Antarctica have also found the same Cambrian, Ordovician benthic or semi-swimming trilobites as in Asia, so it has been cited as one of the evidence of "continental drift". That is to say: Asia, Oceania and Antarctica were originally connected continents in the Paleozoic era, and it was not until the Mesozoic Cretaceous Period, about 100 million years ago, that the continent gradually split and "drifted" to its current geographical location. Therefore, trilobite fossils can be used not only to find underground mineral deposits, but also to infer changes in the Earth's sea and land and as evidence of continental movement.
Invertebrates such as trilobites appeared on Earth so early? There is still no satisfactory answer to this question. It is also one of the major unsolved problems in the history of biological development. In the great world, how much still needs to be developed and explored.