For many people, perhaps most, the term evolution is closely linked to Charles Darwin. One of the many common misconceptions about biological evolution is that this was an idea first proposed by Charles Darwin. In July, 1858, the Linnean Society gathered at its new headquarters in London to hear two papers by Charles Darwin and Alfred Russel Wallace in which they jointly announced a theory of evolution by natural selection. At this time, the concept of evolution was neither new nor novel as it was a commonly accepted idea among scientists during the first part of the nineteenth century. Many naturalists had proposed hypotheses about the mechanisms of evolution.
In his book A People’s History of Science: Miners, Midwives, and “Low Mechanicks”, Clifford Conner reminds us:
“The theory of evolution of species has become so closely linked to Charles Darwin’s name that it is easy to forget that evolutionary biology did not begin with him. Darwin’s contribution was to provide a plausible explanation of how species evolved—that is, by natural selection—and to support it with mountains of evidence.”
At the time Darwin and Wallace were developing their theory of evolution by natural selection, the most widely accepted theory of evolution was one which had been developed by a French naturalist, Jean-Baptiste Pierre Antoine de Monet, chevalier de Lamarck (1744-1829).
In 1800, Lamarck declared that the fixity of species was an illusion. He proposed that species had not all been created in their current form at the dawn of time. New species, he postulated, had formed through spontaneous generation. As species evolved, they achieved higher and higher levels of complexity. Carl Zimmer, in his book Evolution: The Triumph of an Idea, describes it this way:
“The continual emergence of species and their ongoing transformation created the Great Chain of Being: lower members of the chain had simply started their upward journey later than high members.”
In his book Evolving: The Human Effect and Why it Matters, Daniel Fairbanks describes Lamarck and his hypothesis about evolution this way:
“He was a brilliant naturalist who developed one of the first coherent hypotheses to explain evolution. With little understanding of the mechanisms of inheritance (which were not well documented in his day), he proposed that animals evolve through the inheritance of characteristics acquired through the use and disuse of organs.”
The data which Lamarck used came primarily from his work with mollusk fossils from rocks in the Paris Basin. He viewed each lineage as discrete with its own ancient origins. Over time, and with its interactions with the environment, lineages changed and became more complex.
Lamarck saw a material life force or nervous fluid as a key mechanism for evolution. Edward Larson, in his book Evolution: The Remarkable History of a Scientific Idea, explains:
“This force or fluid could transform ‘gelatinous’ matter into the simplest of animals, he claimed, and ‘gummy’ matter into the simplest of plants. Once living organisms form (and this happened continuously, according to Lamarck), the fluid continues to act in them and their descendants—naturally driving them to evolve into ever more specialized forms.”
Edward Larson goes on to say:
“First, external stimuli and internal requirements can cause the fluid to concentrate in particular parts of the body through exercise, stimulating the emergence of a new organ there. Second, the fluid naturally flows toward used organs and away from unused ones, causing the former to develop further and the latter to atrophy.”
This process, according to Lamarck, allows species to adapt to environmental change.
According to Larmarck, as a species adapted to its environment, it passed these adaptations on to its offspring. In their book In the Footsteps of Eve: The Mystery of Human Origins, Lee Berger with Brett Hilton-Barber write:
“Struggling to free himself from the shackles of biblical convention, Lamarck was prepared to countenance the possibility that humans had arisen from an ape-like animal.”
With regard to humans, Carl Zimmer reports:
“Lamarck suggested that humans might have descended from apes that left the trees, stood upright, and walked out onto the plains. The very effort of trying to walk on two legs would have gradually changed their bodies to our own posture.”
In 1809, Lamarck outlined his theory of evolution in Philosophie zoologique ou exposition des considérations relatives à l'histoire naturelle des animaux (Zoological Philosophy: Exposition with Regard to the Natural History of Animals). His proposed theory of evolution is now known as Lamarckism. Lamarck proposed that species could acquire new characteristics from influences in their environment:
“as new modifications will necessarily continue to operate, however slowly, not only will there continually be found new species, new genera, and new orders, but each species will vary in some part of its structure and form ... individuals which from special causes are transported into very different situations from those where the others occur, and then constantly submitted to other influences - the former, I say, assume new forms, and then they constitute a new species.”
In other words, an organism can pass on characteristics that it had acquired to its offspring. In their textbook Human Evolution and Culture: Highlights of Anthropology, Carol Ember, Melvin Ember, and Peter Peregrine summarize Lamarck’s thesis this way:
“…individuals who in their lifetime developed characteristics helpful to survival would pass those characteristics on to future generations, thereby changing the physical makeup of the species.”
In his book A Devil’s Chaplain: Reflections on Hope, Lies, Science, and Love, Richard Dawkins writes:
“Arguments offered against Lamarckian theories are usually factual. Acquired characteristics are not, as a matter of fact, inherited. The implication, often made explicit, is that if only they were inherited, Lamarckism would be a tenable theory of evolution.”
Richard Dawkins also writes:
“Acquired characteristics are attributes of the animal. In order for them to be inherited, the animal would have to be scanned and its attributes reverse-transcribed into the genes.”
Like many others, Lamarck viewed all living things organized into the Great Chain of Being from least complex to most complex, from least perfect to most perfect, with humans occupying the most perfect, most complex position. In his entry on Charles Darwin in The New Encyclopedia of Unbelief, Richard Dawkins writes:
“Lamarck thought that species were arranged on something more like a ladder than a tree, each one transforming itself into the species on the next rung up.”
Lamarck’s idea of the Great Chain of Being also reinforces the view that human races are hierarchical. In his book Evolution: The Remarkable History of a Scientific Idea, Edward Larson writes:
“Many Lamarckians saw the various human races as representing different stages of linear biological development, with the taxonomic status of each reflected in its relative cultural attainments.”
During the last half of the nineteenth century, many American naturalists and others felt more comfortable with Larmark’s concept of evolution than with the idea of natural selection promoted by Charles Darwin. In her book Freethinkers: A History of American Secularism, Susan Jacoby writes:
“Many American naturalists, especially those intent on reconciling science and religion, were drawn not to Christianized Darwinism but to the now discredited concept of evolution based on the eighteenth-century theories of Jean-Baptiste de Lamarck. Lamarck argued that environmentally acquired characteristics could be passed on to the next generation and were responsible for most evolutionary development—a theory that dovetailed neatly with the American faith in progress.”
According to the American neo-Lamarckists, characteristics which arose in the adult in one species could metaphorphose into embryonic characteristics in the next higher species, thus accelerating the evolution of advanced traits in the higher organism. Susan Jacoby writes:
“Lamarck’s theory of the inheritability of acquired characteristics was particularly malleable for ideological ends, whether religious or political, precisely because it rejected any notion of random variations in the universe and insisted that species could have evolved only as the result of some all-encompassing plan.”
Lamarck’s ideas concerning evolution were popular and influenced thinking about evolution not only during the nineteenth century, but during the twentieth century as well. In his textbook Biological Anthropology, Michael Park writes:
“One reason that Lamarck’s idea was popular was that it was one of the first detailed, lengthy, scientific treatments of evolution. It was also a comfortable explanation for an uncomfortable topic. It had become clear that life changed over time. At least, according to Lamarck’s hypothesis, life changed in a particular (and very human-oriented) direction, and it changed by a process that was unfailing and dependent upon something inherent to the organism—Lamarck called this process ‘will. It even followed that no organisms ever became extinct.”
In his book Mankind Evolving: The Evolution of the Human Species, Theodosius Dobzhansky sums up Lamarck this way:
“Lamarck is the author of the first self-consistent theory of evolution, but the mechanisms whereby he hoped to explain evolution are now known to be fanciful.”
In the twentieth century, Larmarck’s concept of evolution was championed in the Soviet Union by Trofim Denisovich Lysenko, Joseph Stalin’s anointed biologist. With regard to Lysenko’s neo-Lamarkian concepts, Susan Jacoby writes:
“…the theory not only wrecked Soviet agriculture for generations, but was used by Communist Party hacks to promote the notion that a Soviet upbringing, free of ‘bourgeois individualism,’ could modify the genes that make up the human brain and produce a new homo Sovieticus. Lysenkoism was a joke to the rest of the scientific world by the 1930’s, but it was no joke in Stalinist Russia and led to the imprisonment and deaths of thousands of Soviet researchers with the courage to stand up for scientific truth.”
More human origins
Human Origins: Sexual Selection
Human Origins: The Great Chain of Being
Human Origins: Homo habilis
Human Origins: Homo rudolfensis
Human Origins: Transitional Humans
Human Origins: Pseudo-Archaeology
Human Origins: Bipedalism
Human Origins: The Large Brain