How many kinds of life are there on the earth?

It is estimated that there are 3 million species on the earth now, which is only 1% of the total species that once existed on the earth. That is to say, about 99% of the species that once existed on the earth have become extinct. According to Dawkins' book, the cycle of extinction of biological species is 26 million years. Because the sun has a sister star named "Nemesis", The sun and her revolve around each other in a cycle of 26 million years. This means that once every 26 million years, Nemesis passes through the Oort Nebula composed of billions of comets, which may disturb the orbits of comets and drive out one or several comets, which may impact the earth's boat. This is an unfounded hypothesis, not even a "scientific hypothesis". Dawkins does not really exist in the book. The other time was in the Cretaceous period 65 million years ago, when 5% of the species represented by dinosaurs became extinct. Richard Dawkins's latest work, Interpretation of the Rainbow, was published in London by British Penguin Publishing House in 1998. The reason why the title of "Interpretation of the Rainbow" was used was because Keats, a famous British poet, thought that Newton had destroyed the poetry of the rainbow. Think of it only as the arrangement of spectra. Dawkins responded to this in "Analyzing the Rainbow": "Finding out the mystery will not lose poetry, on the contrary, the result of finding out is more fascinating and more beautiful." Reading Dawkins' works, we can really feel the shock of beauty constantly. Survival is the greatest miracle. Compared with most planets, our earth is lucky, and even with the most optimistic statistical methods, such an opportunity is only one in a million. Dawkins believes that, We shouldn't regret the relatively short life. In his book, he wrote: "You are lucky because you will die, because many immortal lives have no chance to come into the world at all." He pointed out that just as the dark time greatly exceeds the bright time in the long river of the development of the universe, the unborn life greatly exceeds the people who have lived or lived on the earth. Each of us has obtained 23 chromosomes from our father and mother respectively, which constitutes a unique you and unique. And these 23 chromosomes are randomly selected. It can be seen that there must be a series of coincidences before you and I are born. What a small probability! Therefore, we must cherish and love life. It is estimated that there are 3 million species on the earth now, which is only 1% of the total number of species that once existed on the earth. That is to say, about 99% of the species that once lived on the earth have become extinct. According to Dawkins, the cycle of extinction of biological species is 26 million years. Because the sun has a sister star named "Nemesis", The sun and her revolve around each other in a cycle of 26 million years. This means that once every 26 million years, Nemesis passes through the Oort Nebula composed of billions of comets, which may disturb the orbits of comets and drive out one or several comets, which may impact the earth's boat. This is an unfounded hypothesis, not even a "scientific hypothesis". Dawkins does not really exist in the book. Another time was in the Cretaceous period 65 million years ago, when 5% of the species represented by dinosaurs became extinct.