"life"

In this 5.5 million-year-old cave, not only is there no sunlight, but the environment is also very harsh

Water bears are the common name for retarded animals, and these creatures are so small that their body length is usually no more than 1 mm, so we usually do not notice their presence.

How exactly did such a complex life emerge on Earth? This is a great mystery to modern humans, but we are almost certain that the "birth of life" is a process that has a very small probability of occurring.