Why were earthworms called by Darwin the most important group of animals in evolutionary history ?

Earthworms are known as "ecosystem engineers" because they are able to have an important impact on many of the processes that determine soil fertility. It forms numerous reaction rings in and out of its body and abroad through activities such as feeding, digestion, excretion, and burrowing, thus influencing the biological, chemical, and physical processes of the ecosystem.

Earthworms are able to have an important impact on many of the processes that determine soil fertility.

Because it plays an important role in the evolution of organisms.

Because earthworms play the role of decomposers in nature.

Earthworms can change the fertility of the soil.

Breed the next generation. There are more than 2,500 species of earthworms known.

Because earthworms have saved many species from extinction.

Earthworm is called Dilong in traditional Chinese medicine, and the "Compendium of Materia Medica" says that it has the functions of activating meridians, activating blood and removing blood stasis, and preventing cardiovascular and cerebrovascular diseases.

Earthworms can be beneficial to humans. The movement and excrement of earthworms are very beneficial to improve the quality of the soil, which can keep the soil permeable well and keep the soil in a healthy state, which plays an important role in agriculture.

In recent years, many countries have set up earthworm breeding factories, and the earthworm breeding factories are called "environmental purification devices". Not only that, earthworms can also promote the transformation of acidic or alkaline soils into neutral soils, increase fast-acting components such as phosphorus, and make the soil suitable for the growth of crops.

Natural selection for survival of the fittest.

Things are heavenly, and the fittest survive.

The theory of natural selection is the core of biological evolutionary theory, which refers to the process in which organisms survive and the unfit are eliminated in the competition for survival under certain environmental conditions.

Hope it helps.

Darwin's On the Origin of Species:

The first part is the main body and core of the book, marking the establishment of the theory of natural selection.

In the second part, the author imagines a series of doubts about the theory of evolution from the standpoint of opponents, and then explains them one by one to dispel them. This is a manifestation of the author's courage and the invincible vitality of the doctrine itself.

In the third part, Darwin used his theory of evolution with natural selection as the core to provide a convincing explanation of the evolution of the biological world in geohistory, geographical changes, morphological adaptation, and various phenomena in embryonic development, thus further supporting this theory.

namely, the survival of the fittestNatural selection—Comparison of its power with that of artificial selection—Its power over unimportant traits—Its power over all ages and sexes—Sexual selection—On the universality of interbreeding between individuals of the same species—Conditions favorable and unfavorable to the results of natural selection, namely, hybridization, segregation, number of individuals—Slow action—extinction by natural selection—Divergence of traits, association with disagreement with organisms of any small area, and association with naturalization—Natural selection, The role of the offspring of a common ancestor through the divergence and extinction of traits—Explanation of all biological taxonomy—Progress of biological institutions—Preservation of inferior types—Convergence of traits—Infinite reproduction of species—Summary.

In 1842, he wrote for the first time a brief outline of The Origin of Species. In November 1859, Darwin's magnum opus, On the Origin of Species, which had been written after more than 20 years of research, was finally published. In this book, Darwin clearly put forward the idea of "evolution", showing that species are constantly changing, from the lower to the higher, from the simple to the complex.

The advent of this work for the first time established biology on a completely scientific basis, and overthrew "creationism" and the theory of the immutability of species with a completely new idea of biological evolution. "The Origin of Species" is a masterpiece of Darwin's theory of evolution, marking the formal establishment of the theory of evolution.

The publication of On the Origin of Species caused a sensation in Europe and even in the world. It dealt a heavy blow to the foundations of theocracy, and everyone from the reactionary church to the feudal royal literati went into a rage. They attacked him en masse, slandering Darwin's doctrine as "blasphemy against the Holy Spirit" and violating "the divine right of kings," which is contrary to human dignity.

Probably, Darwin believed that species have a tendency to overreproduce, and that there are interspecific or intraspecific struggles due to limited food and space. The fittest survive, and the unfit are eliminated.

First of all, species are isolated. Evolution is not necessarily a new species.

The interval between species is judged by whether the two are produced or notReproductive isolation。(Of course, in fact, there are many examples of reproductive isolation, although the isolation but the two can actually achieve gene exchange, but this example will be chaotic if you give too many examples, so you can only know that this reproductive isolation is called the birth of a new species).

Evolution, on the other hand, is likely to produce a mutation and form a new trait, and at the same time, this trait is more adapted to the current environment than the old trait, so as to stay--- this process is called evolution.

So evolution may only be a small number of genetic mutations, and the new species and the old species can still reproduce normally, so we can't say that this is a new species.

Second, the vast majority of new species are born in hundreds, or even tens of millions of years, based on geographical isolation and time scales that are difficult for humans to observe in their lifetimes.

So the vast majority of new species are "discovered", not observed. It's hard to know for sure exactly when they evolved.

However, as a result of human intervention, many species have evolved in some sense.

Have you ever eaten seedless watermelon? The watermelon basically does not rely on sexual reproduction to produce offspring (fertile offspring), so we say that the parents of this watermelon are actually reproductive isolation.

What's going on with this watermelon's parents? It turned out that the mother had been treated with colchicine and had her chromosomes doubled. So the female parent is 4ploid and the male parent is still 2ploid.

Similar to this, tetraploid melons are obviously new species compared to diploid melons.

In addition, I don't want to complain about human intervention in the genome to create high-producing penicillin-producing bacteria, which is not available in its natural state.

Of course, you may be very dissatisfied with the above answer, or even angry, this is manipulated by your people, I want the natural state.

There are many examples, the most recent example is the record of a couple named Grant published in the journal Nature in 2018.

It is said that the Greater Daphne Island (belonging to Ecuador) was hit by a severe drought in 1977, and the Grant couple, who had visited in 73, volunteered to go to the island to work for animal protection. The evolution of the local ground finch was inadvertently recorded.

Around the 90s, a subspecies (characteristic: very dark) from the next island arrived on Grand Daphne Island by chance and bred with one of the ground finch, numbered 15210, resulting in a group of fertile offspring (F1) that were essentially identical in appearance

Several of them in F1 breed with the original ground finch to form F2A

At the same time, F1 is inbred internally, and two kinds of offspring are produced: F2B and F2C

After that, F2A was bred with F2B and F2C to obtain two types of F3, namely F3a and F3B

But whether it's F3A or F3B, there is only one offspring that survives, F4

After that, F5 and F6 looked the same as F4.

Individuals starting from F4 are completely reproductively isolated from the original ground finches. (It also does not breed with the subspecies of black finches).

It took less than 20 years for a new species to emerge, which is a very special case.

What is the point of Darwin's "On the Origin of Species"?

Hello, I'm glad to answer for you, it takes time to organize the answer, please be patient and wait for a few minutes The main content of this book is: it clearly puts forward the idea of "evolutionary theory", which shows that species are constantly changing, from low to high, from simple to complex evolutionary process.

Genetic variation, the struggle for survival, and the doctrine of natural selection are the main contents of the book "On the Origin of Species".

In his book The Origin of Species, Darwin explicitly put forward the theory of natural selection for biological evolution.

The most controversial work of the 19th century, most of the views are generally accepted by the scientific community. Darwin was the first to put forward the idea of evolution. Using data from his scientific expeditions around the world in the 1830s, Darwin sought to prove that species evolved through both natural selection (natural selection) and artificial selection (human selection).

The theory of biological evolution and the theory of natural selection is one of the most basic theories of biology, which refers to the variation and inheritance of organisms.

and the evolutionary development, species elimination and species generation processes under the influence of natural selection; There was no life on the earth, about 3 billion years ago, under certain conditions, primitive life was formed, and then, life continued to evolve, until there are more than 1.7 million species in the world today; The theory of biological evolution was first put forward by Darwin, who published the book "The Origin of Species" in 1859, and put forward the theory of biological evolution with the "theory of natural selection" as the core

So the answer is: natural selection