During the many thousands of years that humans lived by hunting, fishing, and gathering wild plants for food and fiber, there was an egalitarian worldview in which humans were a part of the natural world. As humans began to make the transition to a food-producing economy based on raising domesticated plants and animals, a new worldview evolved, a worldview in which humans were separated from the natural world and, often, viewed as dominant over the natural world.
One of the early writings explaining this new worldview came from the Greek philosopher Aristotle (384-322 BCE). As the earliest known comparative anatomist, Aristotle, in his History of Animals, studied the generic features of animals and animal parts. One of his concerns was the classification of nature and Aristotle put forth the idea that there is a ladder of nature, a scala naturae. In his book The Strange Case of the Rickety Cossack and Other Cautionary Tales from Human Evolution, Ian Tattersall writes:
“Still, the universe Aristotle envisaged was fixed and eternal, its every component fixed in a hierarchy from the simplest to the most complex. On the lowest rungs of the ‘ladder of being’ were rocks and other objects that possessed no life force, but just existed. Above these lay the simplest animate things like plants, with the properties of life, growth, and reproduction.”
In Aristotle’s hierarchy, humans, with their power of reason, were placed at the top.
Aristotle flourished and wrote in an era long before Christianity was invented. Long after his death, Christian scholars discovered his works. Ian Tattersall writes:
“…Aristotle’s arrangement was eagerly seized upon by the Scholastic theologians who dominated medieval Christian thought. With Saint Augustine, these scholars were only too happy to equate Aristotle’s prime mover with the biblical God, who presided over a Great Chain of Being in which every living thing occupied its divinely preordained place. Human beings ranked below various kinds of angels, but above the lions and other savage beasts that lorded it over the meeker domestic animals and so on, down the line.”
In his textbook Biological Anthropology, Michael Park describes the Great Chain of Being this way:
“It says that the ideal or essential forms of things are not just a list of equals but are arranged in a ladder or chain, from least complex to most complex and from least perfect to most perfect.”
For those who believed that humans had been given dominion over all other living things by a supernatural creator, the idea of the Great Chain of Being was perfectly logical.
In the eighteenth century, natural philosophers (the early scientists) began to lay out the foundations for the biological sciences. Foremost among them was Swedish naturalist Carl von Linné, who wrote under the name Linnaeus (the Latin form of his name). Linnaeus devised what would become the standard biological taxonomy. Ian Tattersall writes:
“In the eighteenth century it was Linnaeus’s great genius to recognize that the living world was clearly structured, but that this structure could best be classified using an arrangement of sets-within-sets.”
With regard to the classification of humans within this taxonomy, Ian Tattersall reports:
“Linnaeus, the father of modern zoological classification, is revered for having taken the bold and revolutionary move of classifying us among primates, along with lemurs and the monkeys and the apes.”
While the Linnaean taxonomy system was revolutionary, it was still basically hierarchical with humans at the top of the hierarchy. The concept of the Great Chain of Being continued as the model for conceptualizing humans with regard to other species.
In the nineteenth century, evolutionary models proposed by Jean-Baptiste Lamarck (1744-1829), Alfred Russel Wallace (1823-1913), and Charles Darwin (1809-1882) provided new ways for understanding the natural world. However, in many cases the Great Chain of Being continued with humans seen as the logical culmination of evolution. Human evolution was often seen as linear with anatomically modern humans at its apex.
In the twentieth century, however, understanding of biological evolution changed dramatically with the new field of genetics, an understanding of genes and mutation, and, by the end of the century, DNA. It became apparent that evolution was more complex than previously envisioned, and it had no specific direction. In other words, evolution is not hierarchical and the Great Chain of Being is simply a myth.
More Human Origins
Human Origins: Cultural Evolution
Human Origins: The Mind
Human Origins: The Large Brain
Human Origins: The Human Hand
Human Origins: Bipedalism
Human Origins: Sexual Selection