The Greatest Show on Earth

First published in 2009, The Greatest Show on Earth: The Evidence for Evolution is a non-fiction book by British author and evolutionary biologist Richard Dawkins. The book provides an easy-to-understand guide to biological evolution as well as a defense against creationist arguments, which claim that evolution is an unproven theory. The Greatest Show on Earth is Dawkins’s 10th book and was generally well received, although critics noted that Dawkins argues for evolution with a such a fervor that he can be as dogmatic as his opponents. Dawkins is known for popularizing the theory of gene-centered evolution in his 1976 book The Selfish Gene.

Dawkins begins The Greatest Show on Earth by discussing artificial selection. Artificial selection is selective breeding to increase the chances of seeing desirable traits. For example, all dog breeds descend from wolves. They are all members of the same species but have different characteristics. Humans bred dogs over time to get them to display desired traits like short legs or long ears. These desirable characteristics come from individual genes passed on during reproduction that determine how long a dog’s legs will be. Through artificial selection, parents are chosen for reproduction with similar desirable characteristics in hopes that these traits will appear in their offspring.

Dawkins describes that this is essentially how evolution works, except the selection process happens naturally. Even though the world is made up of an extremely wide variety of species in a wide variety of environments, if you trace each species back far enough, you will see that there are common ancestors that link all species together. These common ancestors evolved into different species because they were geographically separated. This can be traced back to the separation of the continents due to plate tectonics or to natural disasters like earthquakes or floods that change the nature of landscapes and environments. This separation and the need to adapt to new environments is part of what drives natural selection.



Natural selection is driven by mutations within the gene pool. Each species has a gene pool. The gene pool represents all the potential genetic variations within a species. Mutations occur when genetic information gets corrupted during reproduction, adding new possible variations into the gene pool. Natural selection helps beneficial genetic mutations survive within a species while helping to eliminate mutations that may eventually make a species weaker. Individuals with these beneficial mutations are more likely to survive longer and reproduce.

Natural selection can be seen in predator and prey relationships. Predators evolve to be faster than their prey to be more successful hunters. Their prey evolves to be faster to avoid being caught. The two species’ evolutions inform each other. Evolution of specific traits can have repercussions. A gazelle that has evolved to have thin, fast legs may also have legs susceptible to breaking, which could easily cause them to be caught and killed. As a result, only the gazelles with stronger fast legs will survive, ensuring their offspring will be more likely to have stronger legs.

Dawkins discusses how it is possible to link all life on Earth together through an evolutionary family tree. He notes that this is proof of evolution. For example, you can see similarities between human and bat skeletons. Human hands and bat “hands,” or wings, have a similar layout known as homology. The bat’s fingers have just been stretched wider to support the wing. Their skeletons show that mammals had a single common ancestor, similarities which are visible at the molecular level. DNA’s building blocks are the same across all forms of life, pointing to a shared ancestry.



The last section of The Greatest Show on Earth is devoted to providing evidence to dispute many common creationist arguments against evolution. These arguments include the inability to see evolution in progress over a short span of time, the assertion that the earth is only 6,000 years old, and the argument that life was created by a God or an intelligent designer.

Dawkins explains that while evolution often occurs over millions of years, the processes of evolution can be seen within the span of a few decades. In the 1970s, scientists relocated lizards from one Mediterranean island to another island with no lizard population. In 2009, scientists returned and found that the lizard species had adapted to the new environment. These lizards formed an entirely new sub-species of lizard in the span of a few decades, providing evidence of the evolutionary process.

To disprove the biblical claim that Earth is only 6,000 years old, Dawkins discusses how scientists measure the age of the earth. He notes that we can prove the earth is 4.6 billion years old and that life has evolved not only quickly, but over a long period of time. This can be confirmed through a series of techniques ranging from basic practices like counting tree rings to advanced methods like carbon dating.



Science indicates that evolution has left flaws and mistakes within the makeup of many species. While Creationists believe that God created life, Dawkins asserts that species created by an intelligent designer would be perfect. Humans have remnants of tails beneath the skin, a trait that is not necessary or utilized, which contradicts intelligent design.

Many creationists also point to gaps in the fossil record as proof that evolution is not real. For example, if crocodiles evolved into ducks, they ask: “Why are there no fossils of a ‘crocoduck’ creature?” This idea misunderstands how evolution occurs. No “crocoduck” ever existed because no modern species descended from another modern species—they all descended from a much older common ancestor. This means that a “crocoduck” fossil never existed.

Dawkins concludes The Greatest Show on Earth by restating his thesis that evolution is not a matter of opinion but instead a scientific fact backed up by a wealth of evidence. He notes that there is a hubristic element of believing in evolution, a scientific concept that leaves no space for considering the suffering that happens as a result of natural selection. Although this may be a distasteful aspect of evolution, Dawkins insists that it is just one truth of the world, and truth must be faced at any cost.