Buzz
After circumnavigating the globe, Charles Darwin—assisted by Alfred Russell Wallace—became convinced that nature was governed by a mechanism he termed 'natural selection.' This process drives evolution, where organisms that survive long enough to reproduce pass their traits to future generations. Those that perish, for any reason, see their traits removed from the gene pool. Over time, the accumulation of advantageous traits can give rise to a new species, better suited to its environment than its predecessors.
The concept of evolution is widely accepted as a scientific truth. However, earlier thinkers grappled with explaining the origins of life, and even today, there are those who challenge or attempt to refine Darwin's theory.
10. ‘Paradisical Mountain’ - Carolus Linnaeus
Pre-Darwin (1707–1778)—Carolus Linnaeus was a key figure in the development of modern biogeography. Linnaeus is credited with establishing the Latin binomial nomenclature—for instance, Homo sapiens—which is still in use today. Through this system, he classified thousands of plant and animal species.
Like many of his contemporaries, Linnaeus believed that the creation and flood stories in the Biblical book of Genesis were factual. As such, any discovery he made or theory he proposed had to align with this worldview. To accommodate this belief, Linnaeus developed the concept of the 'Paradisical Mountain.'
Linnaeus proposed that, in the past, there was a vast island mountain along the equator, featuring various biomes at different altitudes. This was the site of creation, and all life forms were made there, existing as they do now. As waters receded from the island, creatures dispersed across the globe to their present locations. This cycle was repeated after Noah’s flood, this time on Mount Ararat in Turkey.
Although Linnaeus was highly regarded in his time, his Paradisical Mountain theory faced criticism. How could animals like penguins endure a journey across the desert to reach their polar homes? And why would camels be found in one desert but not others?
9. ‘Northern Origin’ - George Louis LeClerc, Comte de Buffon
Pre-Darwin (1707–1788)—George Louis LeClerc, Comte de Buffon, was a French scholar who took it upon himself to compile a monumental 44-volume work summarizing humanity's understanding of the natural world, titled Historie Naturelle.
Buffon also observed that similar yet isolated regions supported different types of life. For instance, although the Arctic and Antarctic share similar climates, penguins are absent from the North. This observation led to the development of 'Buffon’s Law,' a principle that remains valid today.
He dismissed Linnaeus’s Paradisical Mountain theory, proposing instead that God must have created all animals, as they are, near the North Pole during a warmer period. From there, they spread out across the planet. Buffon found this idea more convincing than the notion of a distribution from Mt. Ararat. He also believed that organisms could change over time, though his explanation for how this occurred was based on 'organic particles'—environmental components that could alter organisms.
8. ‘Mountains Of Origin’ - Karl Willdenow
Pre-Darwin (1765–1812)—Karl Ludwig Willdenow was a German scholar, primarily known as a botanist. Like Linnaeus, Willdenow classified thousands of species. At the time of his death, his herbarium contained 20,000 specimens, which can still be viewed today at the Berlin Botanical Garden.
He expanded on the Paradisical Mountain idea, proposing that although there was only one creation event, there were several origin sites—mountains that existed above sea level during the Earth's formation and the flood. Willdenow likely developed this theory due to his focus on plants, as their immobility might have made it difficult for him to imagine all plant species spreading from just one location.
Willdenow suggested that each of his proposed mountains supported a distinct biota, and when the waters receded, the plants and animals—created as they are today—descended from these mountains, spreading out to form the different regions of the Earth.
7. ‘Lamarckian Evolution’ - Jean-Baptiste Lamarck
Pre-Darwin (1744–1829)—If you've ever taken a biology course, you've likely encountered Jean-Baptiste Lamarck. His ideas on evolution are often criticized by professors and textbooks just before Darwin's theory is introduced, as Lamarck’s concepts have been proven incorrect.
Lamarck’s evolutionary hypothesis was primarily based on the idea of 'use and disuse.' He observed many organisms had vestigial structures and proposed that animals who frequently use a particular organ or limb would adapt it for increased function. Characteristics acquired during an individual’s lifetime could then be passed down to their offspring. For instance, a giraffe stretching its neck to reach tall branches would supposedly have offspring with longer necks.
The 'use and disuse' theory was a reasonable working hypothesis before Mendelian genetics came to light, but it has clear flaws. For example, if a parent lost a leg in an accident, their child would not be born without a leg. Or, even if a parent dedicated their life to building muscles, it wouldn’t mean their child would automatically have a more muscular build.
Lamarckian evolution influenced Soviet horticulturist Ivan Michurin, who inspired Trofim Lysenko and Joseph Stalin to apply Michurinism to Soviet agriculture. The results were disastrous, and it took 20 years to eradicate it.
6. ‘Basic Forms’ - Anonymous
Post-Darwin (2011)—'X-Evolutionist' is a Christian blogger with a very specific agenda, as her username suggests. Though she lacks the academic credentials of others on this list, her unique perspective on evolution challenges conventional ideas about species classification.
X-Evolutionist proposes that there are several 'basic animal forms' on Earth, such as cats, bears, or dogs. She argues that humans, despite appearing different due to environmental factors, are still the same species and capable of interbreeding. She applies this reasoning to other animals, claiming that dogs, wolves, and coyotes are all variations of the same species since they can interbreed, though they look different due to environmental influences. Similarly, she applies this concept to bears—polar, grizzly, and black—and to lions, tigers, and elephants.
It’s a well-thought-out theory, as many species and subspecies are indeed capable of sexual reproduction. X-Evolutionist uses this logic to argue against the protection of endangered species, asserting that no form of life can be completely eradicated.
But this idea heavily relies on the Biological Species Concept, which defines species as groups capable of interbreeding. However, this is not the only way to classify species. Moreover, it’s easy to think of basic forms that can’t interbreed: Pandas and sun bears can’t reproduce with polar bears, leopards can’t mate with cheetahs, and so on.
5. ‘Apeiron’ - Anaximander
Pre-Darwin (610–546 B.C.)—Anaximander was an Ionian philosopher. In classic Greek style, he presented his views on the natural world in a lengthy poem called 'On Nature.'
To modern scientists, Anaximander’s ideas on the origins of life resemble early evolutionary theory. He proposed that the Earth originated from a formless substance known as apeiron, from which the planet began to form. Life, including plants and animals, emerged from mud, with the first animals being fish. Humans, according to Anaximander, evolved from these early aquatic creatures.
In addition to his poem, Anaximander also attempted one of the first world maps and dabbled in astronomy. However, much of his work is lost to history, leaving us uncertain whether he ever studied fossils, or how much of his 'On Nature' was based on actual observations of nature or simply the mythological beliefs of his time.
4. ‘The Selfish Gene’ - Richard Dawkins
Post-Darwin (first suggested in the 1960s)—While most biologists, especially Darwin, understood natural selection as functioning at the level of populations of organisms, some biologists in the 1960s proposed that natural selection might actually be more accurately described at the level of the gene. This idea was brought to the forefront by renowned biologist Richard Dawkins in his 1976 book, 'The Selfish Gene.'
The gene-centered view of evolution posits that every gene within an organism is in competition with alternative versions of the same gene—known as alleles. In essence, genes act largely on their own, utilizing the bodies of larger organisms—like a dog or a tree—as vessels to ensure their own survival. Dawkins argues that focusing on evolution at the level of the organism is flawed, as it presumes cooperation between genes within the same body, whereas in reality, these genes are in competition.
A gene-centered perspective of evolution is understandable when considering the widely accepted theory that life emerged from a primordial soup. However, this view faces several objections, including the fact that some reproducing populations don’t exchange alleles, and certain alleles rely on others for survival.
3. ‘The Laws of Organic Life’ - Erasmus Darwin
Pre-Darwin (1701–1832)—Though the young Charles Darwin seemed uncertain and directionless, his grandfather, Erasmus Darwin, was a leading intellectual figure of the 18th century. A naturalist, botanist, physician, philosopher, and poet, Erasmus was a man of many talents. Like Anaximander, he shared some of his observations about nature in verse. Erasmus distinguished himself by taking an integrative approach to studying life, exploring both domesticated and wild animals and examining subjects such as paleontology, biogeography, embryology, and anatomy.
Erasmus proposed that life originated from a single common ancestor, though he struggled to explain how species evolved. Though unaware of Lamarck's theories, Erasmus’s ideas of “use and disuse” closely resembled Lamarckian evolution. Still, Erasmus also anticipated his grandson’s ideas by moving beyond “use and disuse” to suggest that sexual selection and competition could also drive changes in animals.
2. ‘The Struggle for Existence’ - Al-Jahiz
Pre-Darwin (776–868)—Al-Jahiz was an influential Islamic scholar who wrote extensively on various subjects. One of his most famous surviving works is the Book of Animals, where he articulated biological observations that bear a striking resemblance to Darwin's theory of evolution.
Al-Jahiz presented his ideas in three parts: The Struggle for Existence, The Transformation of Species, and Environmental Factors. He suggested that every individual is in a constant battle for survival. Environmental influences enable organisms to gradually develop new traits, sometimes leading to entirely new species, which in turn helps them compete more effectively in the struggle for existence.
Although Al-Jahiz may not be a direct precursor to Darwin, he certainly precedes Lamarck in some respects. The key distinction is that as a devout Muslim living in medieval Iraq, Al-Jahiz attributed the shaping of life to God’s will, suggesting that divine influence played a significant role in evolution.
1. ‘Neutral Theory of Molecular Evolution’ - Motoo Kimura
Post-Darwin (first introduced in the late 1960s)—Motoo Kimura was a renowned Japanese biologist who conducted research both in Japan and the United States, publishing numerous influential papers. He made significant contributions to the fields of migration, genetics, and natural selection. Perhaps his most notable concept is the Neutral Theory of Molecular Evolution, which argues that some molecular-level changes in evolution do not necessarily have a specific purpose or adaptive advantage, but rather are neutral in an organism’s evolutionary struggle.
The Neutral Theory is often misunderstood. While a population or organism may adapt to its environment due to natural selection, Kimura proposed that certain mutations within a population or individual may have no direct benefits or harms. These neutral mutations persist simply through genetic drift. The Neutral Theory does not dismiss the role of natural selection at the organism or population level, but it emphasizes that not every trait within an organism is a result of natural selection.
+ ‘Punctuated Equilibrium’ - Niles Eldredge and Stephen Jay Gould
Post-Darwin (first proposed in 1972)—Although we’ve already touched on the concept of punctuated equilibrium, it is too significant to omit from any discussion of evolutionary theory. Darwin’s theory of evolution suggests that species evolve gradually over time, slowly accumulating new traits until a new species emerges.
In contrast, punctuated equilibrium posits that most of the time life remains relatively unchanged, but then undergoes rapid evolution in response to a dramatic event. Many scientists consider punctuated equilibrium as a refinement or successor to Darwin's original theory, as it aligns better with the fossil record and can even be witnessed in real-time.
