On The Shoulders of Giants: Ancient Western Theories of Evolution

What was the first theory of evolution?

The theory of evolution, as we know it today, is often attributed to the great Charles Darwin. His works, primarily his book On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, have defined the theory as a coherent scientific principle ever since being published in 1859.

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This book is widely seen as the foundation of Evolutionary Biology which, by extension, makes Charles Darwin the Father of Evolution. But, like many things in science and technology, his work was built on that of a series of developments over time. 

In fact, the premise that life has changed over time is nothing new. It has very deep historical and philosophical roots indeed.

What follows is a summary of some of the key figures in history who have helped lay the foundations for the development of this world-changing theory. This is not intended to be a comprehensive guide.

The first steps were taken by the Ionian philosophers

Evolution, as a concept, can trace its early origins to classical antiquity. One man, in particular, Anaximander, made significant advances in human thinking about life on this planet.

He lived between the 6th and 7th centuries BC, and we know very little about him today. But fragments of his work have survived the ravages of time.

The most critical one, for our purposes, was his poem On Nature. Sadly we don't have examples of the complete work, but what remains is fascinating - given its age.

He believed that the world had arisen from an undifferentiated, indeterminate substance, called the Apeiron. The Earth was formed from this substance, and life coalesced from the mud.

But, most critically, Anaximander goes on to describe how human beings did not exist at this time. They came later and developed from fish. 

It is important to note that his work was grounded in religion and mythology, but he was still one of the first to attempt to explain the origin of species from natural laws.

This insight is incredible for us today. He is, more or less, on the right track but cannot offer a mechanism for the process.

The poem would prove to be very influential on future philosophers, like Aristotle. Though Aristotle would famously believe that species' were custom built, to borrow a phrase, for their place in the world.

Xenophanes might be the first paleontologist

A student of Anaximander, Xenophanes of Colophon might be the first documented paleontologist. By studying fossils he further developed his master's ideas.

By observing fossil fish and shells he concluded that where they were found must have been under water at some point in the past. He also thought that the world formed from the condensation of water and "primordial mud." 

Later thinkers, like Herodotus and Hippocrates of Cos, also conducted similar work to Xenophanes. Whilst their conclusions were more based in Greek mythology, they provided very early work on showing the world, and life changes over time.

A little later, in the 5th Century BC, another Greek philosopher, Empedocles, further developed the work of his forerunners. He supposed that everything in the Universe was made of four basic elements (earth, air, fire, and water). 

He postulated that these were all stirred together and were constantly repelling and attracting one another. Empedocles of Acragas also claimed that life was created by the planet, but early ones had been disembodied organs. 

Over time, they finally joined together into whole organisms. This, whilst a little odd, is an early attempt to describe a process very similar to evolution. 

Lucretius was the high-water mark in Antiquity

A similar theory was proposed by the Roman poet and philosopher Titus Lucretius Carus in the 1st Century BC. Clearly inspired by Empedocles, he suggested that some kind of 'selection' process occurred that caused "monstrous" organisms to die out and others to survive.

Survival, according to Lucretius, was due to their superiority (stronger, faster, etc.) over others. But, it is important to note that he did not believe that new species could form from older existing ones.

His work would prove incredibly influential to future philosophers, but that's about as far as ancient western philosophy reached before the dominance of Abrahamic religious thinking around Europe. 

Advancements in our understanding of evolution would not make significant progress until the Renaissance and Enlightenment over 1500 years later.

The Age of Enlightenment dawns

With the rise of The Enlightenment, the works of earlier philosophers were rediscovered by European thinkers (though existed in part within religious doctrine). During this time, some basic components that would help build Darwin's work were forged.

Taxonomy, for example, was born during the 16th and  17th Century thanks to the great work of scientists like Swedish botanist Karl von Linné (Carolus Linnaeus) and the English naturalist John Ray.

The concept that life forms can change over time was proposed by later scientists during the 18th Century. One notable example was French mathematician and naturalist,  George Louis Leclerc, Comte de Buffon.

But, in the late 17th Century, one Erasmus Darwin(grandfather of Charles) proposed a theory that was clearly very influential to his grandson. Erasmus outlined a hypothesis whereby species transmitted over time. 

Jean-Baptiste Lamarck later published a more developed version of Darwin's theory in 1809 and was heavily supported by his colleague Étienne Geoffroy Saint-Hilaire.

Georges Cuvier, a French naturalist, was one of the first to establish the reality of extinction in nature in the past. He also suggested that is was caused by local catastrophes whereby new species repopulated the area soon afterward.

Other important additions to the developing theory of evolution occurred across Europe at the time. William Paley, for example, suggested that adaptation of species for specific environments was a beneficial design by the creator. 

Other advancements in thinking in the field of Geology would also add weight to Darwin's later conclusions. James Hutton and Charles Lyell showed that the Earth was very old indeed and that past processes were very similar, if not exactly the same, as the present day.

"The present is the key to the past"

This would ultimately lead to the development of the theory of uniformitarianism. 

But, on the whole, the scientific community was resistant to these ideas at the time. At this time, most scientists were very pious and saw such suggestions as a threat to religious doctrine.

Was Darwin the first to come up with evolution?

As you have already seen, components of his theory either already existed or had been partially developed. But this is not to say that Darwin's work was not groundbreaking.

It simply shows that Darwin didn't develop his theory completely out of the blue.

But, this is probably a good point to mention one Alfred Russel Wallace. The two men, working independently had managed to create very similar theories on the evolution of life.

The two men were also in contact and bounced ideas off each other. After Wallace sent Darwin an extract of his theory, Darwin realized the similarity to his own work. 

This ultimately led to two men jointly publishing their work in 1858 to the Linnean Society. But it drew little attention at the time. 

Whilst similar on the surface, what is new in Charles Darwin is not his theory of descent, but its confirmation by the theory of natural selection and the survival of the fittest in the struggle for existence. From this perspective, it was an entirely revolutionary way of looking at life on Earth. 

Darwin also placed more emphasis on natural selection making various comparisons to 'artificial selection' in many domesticated animals, like pigeons. Wallace, on the other hand, was more focussed on ecological pressures that forced species to adapt. 

But ultimately it was Darwin who first published his complete theory in 1859. Whilst it was continuously edited afterward, it would come to revolutionize scientific thinking on evolution to the present day.

When as Darwin's theory accepted?

Darwin's work was initially met with hostility, and often ridicule. But it would gain traction over time ultimately leading to the development of a school of scientific thought called "Darwinism."

This term was coined by Thomas Henry Huxley in 1860. But, Charles Darwin's work wasn't really accepted until the approximate period of the 1880s to about 1920. 

The Theory of Evolution would later become combined with other fields of science, like genetics, and "Darwinism" as a term has largely become redundant as a term in favor of Evolutionary Biology.