How did animals originate? Whether small dot fossils can solve the mystery of animal origin.

How did animals originate? This is an important scientific issue that has long plagued paleontologists and evolutionary biologists.
600 million years ago in Guizhou's Yan'an biota, there are many small fossils, almost invisible to the naked eye, including a kind of embryonic fossil surface with a strange spiral coil, this is what kind of life? A paper published online June 13 in the Us sub-issue of Science Advances reveals the mystery of the worm.
an international team led by the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences, through high-resolution micro-CT and synchrotron radiation microtomography technology, studied the internal structure of such fossils, and finally solved the mystery of their lives.
less than millimetres of fossils with spiral coils of the Zi'an biota are located in the phosphate-bearing formation of the storitary group in the Yan'an-Edikara system in Guizhou, and the fossils of 600 million years ago were preserved intact by phosphate.
the fossils are called the dawn of the animal world, and scientists believe they are the oldest known creatures of the Earth.
there are a large number of millimeter-grade small fossils, about their identity, there have long been various hypotheses in the academic community, but there is not enough evidence to prove it.
2006, researchers found a class of embryonic fossils in the Luan biome with strange spiral coils on their surfaces, and named them the cynosis.
the cynta is spherical and develops a bag decorated with a large accumulation ball similar to the common Yan'an embryonic fossil, which also develops a spiral coil that extends from one pole to the other.
some people think that they are the embryos of the hedgehog sacinted, the embryos of the eight-arm fairy worm, green algae, animal single-cell close relatives and so on.
also scholars believe that they are independent species, single-celled perforated insects. Yin Zongjun, a researcher at the Nanjing Institute of Geology and Paleontology of the
Chinese Academy of Sciences, told Science and Technology Daily that embryonic fossils in the Yan'an biota, as well as large cumulus balls, spinners, caged ridgeballs, and so on, have developed similar decorative bags.
November 2019, the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences published a paper saying that the 610 million-year-old cage-ball fossils found in the Yan'an biota provide important clues to the mystery of the animal's origin.
experts, for example, likened the first animal on Earth to a "chicken", and if there were "eggs" with complex embryonic development mechanisms, caged spine fossils were the "eggs".
small-point fossils can solve the mystery of animal origin For a long time, because the earliest animal fossil record is difficult to find traces, the field of animal origin has been the dominant theoretical study of evolutionary developmental biology, until the discovery of a large number of animal embryonic fossils in the Edikara Ji'an biota, this situation began to change.
the biological properties of embryonic fossils in the Yan'an biota have been controversial in the past, research in recent years has evolved to lead to convergence of understanding of these fossils: some of these groups may represent the earliest animals (including dry animals), while others may represent single-cell close relatives of animals.
While it is difficult to identify which animals are animals and which are close relatives of animal singular cells, it is not controversial to place these embryonic fossils within the animal's general boundary.
, these specimens at the cellular level preserve different stages of development, making it possible for palaeontologists to examine animal origin models proposed by evolutionary developmentbiologists through the fossil record.
Yin Zongjun told reporters that there are two ways to know how animals originated: one is evolutionary developmental biology theory, that is, from the molecular level to compare the development of animals and their single-celled close relatives of the development process, in molecular biology built in the animal general boundary time tree (animal general boundary includes all successors and their single On the basis of cell close relatives, the biological characteristics of animal ancestors are inferred and the systematic process of reconstructing these characteristics is estimated to occur, while the other approach is the empirical study of paleontology, which reconstructs the process of animal origin and determines the upper limit of the origin of the animal by tracing the fossil record of the earliest animals and their close relatives.
at present, the research work on the evolutionary developmental biology of the animal general boundary group in the Yan'an biota has just started, and there are still a large number of difficult fossils with unknown system classification locations, some of which are very similar in appearance of the animal embryo-like fossils - the slug stoicisis is one of them. The main reason why
is what is the biological property of the slug-in-the-hole worm is is that its internal biological structure is not clear.
to this end, Yin Zongjun Researcher of the Early Life Research Team of Nanjing Institute of Geology and Paleontology of the Nanjing Institute of Science of Chinese Science, Zhu Maoyan Researcher, Liu Pengzhang Researcher of the Institute of Geology of the Chinese Academy of Geosciences, and Philip Donoghue, Professor of the University of Bristol in the United Kingdom, in collaboration, scanned more than 300 fossil specimens of the Yan'an transboonicworm, and finally found more than a dozen fossils that preserved the beautiful internal biological structure.
researchers found that the larvae, like the large cumin spheres and the spincells, had a similar developmental process, from the single-cell stage through non-growth cell division to the thousands of cell stages.
this development process indicates that the crucible sacposome sacposomes cannot be single-celled perforated, nor are they early or late stages of development of large cumulus or cyclocytes.
the various hypotheses put forward by the previous people based on their similarity to large cumulus balls and spinners are not true.
, Yin Zongjun believed that the spinners belonged to the animal community.
and the development of cyclicworms also provide syups important clues to understanding the origin of animals.
Yin Zongjun said that embryonic fossil packages in the Yan'an biota all developed similar decorative bags, a feature that is the result of convergence and evolution.
almost all embryonic fossils developed similar thick-walled sacs to protect themselves due to the harshness of the marine environment in the early Edicara era and the unstable state of redox.
but this similar cystic structure masks the biodiversity of the Yanan biome, meaning that there may be many more fossil groups in the Luan biota that are not found in the animal boundary, and that there should be greater potential to be tapped in the future.
Source: Science and Technology Daily Zhang Wei.