The feeling I get, is that with hindsight, despite the opposing theories and disagreements, one can say that nearly everyone was right (according to our present state of knowledge) in some way.
Jean-Baptiste Lamarck (1744 – 1829)
Proposed that animals gradually evolve, driven by two ‘forces’, one that causes them to become more complex, and another causing them to adapt. He believed that the more or less an animal uses an organ, the stronger or weaker it becomes. Characteristics acquired in this way are passed on to the next generation. Published Philosophie zoologique in 1809.
Georges Cuvier (1769 – 1832)
He was very critical of Lamarck’s idea that animals changed gradually, reasoning that any change in one part of the animal wouldn’t work with the rest of the animal and render it unable to survive, and pointing out that fossil remains of animals didn’t show gradual changes, rather a form appeared in the fossil record abruptly, continued unchanged for a time, then disappeared. He also conclusively demonstrated that some fossils were of animals that were now extinct. He explained the appearance of these new types of fossil animal not through evolution, but by saying they had immigrated from other parts of the globe.
Claude Bernard (1813 – 1878)
A physiologist, he came up with the idea of homeostasis. He argued that all species were fundamentally alike, and that differences between species were just sort of quantitative – that is the differences between a frog and a dog say, were just a matter of differing sizes and arrangements of the same fundamental organs.
Charles Robert Darwin (1809 – 1882)
Co-discoverer of evolution by means of natural selection. Published On the Origin of Species in 1859.
Alfred Russel Wallace (1823 – 1913)
Co-discoverer of evolution by means of natural selection. He became a spiritualist, arguing that evolution couldn’t account for the human mind. Published On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection in 1859.
Gregor Johann Mendel (1822 – 1884)
Discovered the laws of genetics through his work on peas. Published Experiments on Plant Hybridization in 1866.
Francis Galton (1822 – 1911)
Originated the concepts of eugenics and ‘nature vs. nurture’ in his investigations in to human heredity. Published Inquiries into Human Faculty and its Development in 1883.
D’Arcy Wentworth Thompson (1860 – 1948)
Emphasised the limitations on the direction evolution could take, imposed by necessities of body structure and growth/development. Published On Growth and Form in 1917.
Friedrich Leopold August Weismann (1834 – 1914)
Came up with the Germ plasm theory; the idea that the genes you pass on (the Germ cells) are kept separate from the rest of your body (the soma), and aren’t influenced by what the organism does in it’s life. In a human the germ cells are the sperm and eggs, the soma being the rest of you.
John Burdon Sanderson Haldane (1892 – 1964)
Worked out some of the math for how the frequency of genes in a population will change with selection pressure. Published The Causes of Evolution in 1932.
Ernst Walter Mayr (1904 – 2005)
Articulated the biological species concept – that what differentiated two species was their inability to produce viable offspring, rather than differences in how they looked and so on. Criticised reductionism in biology like that of Richard Dawkins. Published his book Systematics and the Origin of Species in 1942.
The Modern Synthesis (1936 – )
This is the name given to the organising of Mendel’s laws of genetics, Germ plasm theory and population genetics under Darwinian evolution in to a grand unifying biological paradigm.
Watson & Crick (1928 – ) & (1916 – 2004)
Discovered the double helix structure of DNA in 1953.
Richard Dawkins (1941 – )
Argues that evolution only happens through natural selection increasing or decreasing the frequency of specific genes, and that behaviours like altruism, that at first sight wouldn’t seem to improve your own chances of passing on your genes, can be explained by this – as argued by evolutionary psychology. Popularised this gene-centric view of life in The Selfish Gene, published in 1976.
Stephen Jay Gould (1941 – 2002)
Came up with ‘punctuated equilibrium’ – the idea that evolution happens in stutters of rapid change rather than at a gradual continuous rate. Was critical of evolutionary psychology and argued that many aspects of organisms weren’t due to natural selection, but rather were consequences of developmental constraints, or unintended/non-selected consequences of other adaptations. Helped to create the field of evolutionary-developmental biology, with his book Ontogeny and Phylogeny published in 1977.
The Human Genome Project (1989 – 2003)
The effort to sequence the entire human genome (well actually the genetic material was taken from a load of anonymous donors). It found only 22,000 genes, and that only about 1% of the genome codes for proteins, things that we know actually do something.