Evolution

Evolution is the natural process by which living organisms arise and form into new species. It occurs through the random mutation of genes, with the natural selection of traits that are advantageous to the organism.

## Summary

Evolution is the driving force behind the diversity of life on Earth and, assuming life exists elsewhere, on other planets. Life evolves according to specific conditions, with traits that are advantageous to an organism's survival being selected for. This occurs through the inheritance and mutation of DNA, and through the process of natural selection. Evolution has been observed at all levels of life, from the simplest bacteria, fungi, algae, and plants, through to more complex animals such as fish, amphibians, birds, reptiles, mammals, and, finally, primates, including humans. The fossil record can also be used to infer evolution, providing information about the past and future of life on Earth.

## Evidence

The evidence for evolution (which is frequently ignored/denied by anti-science supporters such as creationists and young earthers) is plentiful. The fossil record preserves a number of species which, while more often than not close relatives of others rather than direct ancestors, paint a picture of how certain species may have arisen. An example of this is the tyrannosaurid *Daspletosaurus horneri*, which is directly ancestral to *Daspletosaurus torosus*. Another piece of fossil evidence comes from the numerous extinct species within the tribe Hominini, which includes humans. Most importantly, though, there is evidence from extant species of evolution:

1. In as few as ten generations, the marine stickleback (a type of fish) can shed its defensive structures in order to form a form better suited for more agile locomotion in freshwater environments.
2. In recent times, African elephants have began to lose their tusks in response to poaching. This is a process which could only be explained by the process of natural selection, and reflects ecological pressures.
3. Antibiotic, herbicide and pesticide resistance in microorganisms is an example of microevolution.

Nevertheless, when confronted with such evidence, creationists often claim that microevolution is entirely different to macroevolution—the most popularly understood sort—despite this not really being the case. The only major difference is time. More evidence for evolution comes from the diversity of organs such as eyes within the natural world. If there was truly some almighty creator, why would some animals have poorer eyesight than others, rather than being equally well-adapted? And why would wings, flippers and arms be derived from the same exact bones in tetrapods? Such forms are more likely to arise naturally, from the natural world. Charles Darwin, commonly considered the father of evolution—despite the idea having come about earlier—was aware of this. Anti-science movements and people (especially creationists) simply deny this, as well as the extinction that we currently are unleashing upon the world.

## Who proposed the theory of evolution?

As stated before, Charles Darwin is often considered the proponent of the theory of evolution, and the idea is typically claimed to have come solely from him. However, evolution had been proposed twice before: once by Jean-Baptiste Lamarck in the 1800s, and even earlier by Erasmus Darwin (who was, of course, the grandfather of Charles Darwin). While Erasmus Darwin did not publish his findings in a formal book, instead publishing them in the form of poetry, the point still stands that he concieved the theory of evolution long before his grandson.

There were many other independent suggestions of the theory of evolution, though; among many, the French philosopher Georges-Louis Leclerc suggested that lions, tigers, leopards and house cats shared a common ancestor. He also suggested that the 200 or so mammals known at the time originated from as few as 38 original species. While he believed that each form arose through spontaneous generation, the point stands.