Timeline of Evolutionary Theories

a species. He furthered his ideas by indicating that the variations in a species could be acted on in the natural environment through natural selection but didn t believe that new species could come from this. Instead, he believed that natural selection kept a species in its truest form.

Robert Chambers published a book anonymously in 1844 that greatly opposed the religious views of his era. He wrote that the solar system developed from a nebula and that life sprung up on earth spontaneously. He didn t understand how evolution actually happened. The book was believed to have prepared the public for the work of Charles Darwin.

Charles Darwin and Alfred Wallace wrote a joint paper in 1858 on evolution through natural selection. In 1959, The Origin of Species was published that showed evidence of natural selection. It left essentially no question in the minds of scientists that natural selection existed. This did not make it instantly popular, however. It was not fully accepted until the 1930s by most scientists.

TIMELINE OF EVOLUTIONARY THEORIES

In this section, we will talk more about the timeline of evolutionary thought. There have been ideas related to evolution in the ancient cultures of the Romans, Greeks, Chinese, and Islam. There were two opposing thoughts that were discussed as part of the evolutionary debate. The first was essentialism”, which argued that every species on earth has unalterable characteristics. This was in line with the theology of the time. The second was evolutionary cosmology along with naturalism, which was the idea that the different species characteristics were variable.

We ve already talked about early evolutionary thought; however, evolutionary thinking has changed in recent years with the knowledge about genetics and biology contributing to modern synthesis. This looks at genetic diversity in species populations and applies the study of paleontology and comparative anatomy to determine how the different species have evolved over time. Most recently, DNA sequencing has led to an understanding of phylogenetics from a molecular perspective. We will talk about the current three-domain system of all life, that was developed by Carl Woese, later in this course. For now, you should know that this is a relatively recent phenomenon in evolutionary thinking.