tl;dr: I am published!
What did early geneticists such as William Bateson, Hugo de Vries, Thomas Hunt Morgan and R.C. Punnett contribute to evolutionary thought? Nothing, according to many scientific sources. They aren’t included in various timelines of the history of evolutionary biology and most are not included in the Oxford Encyclopedia of Evolution. When they are mentioned with regard to evolution, they are depicted as fools who missed the big picture, rejected natural selection, and developed a dead-end “mutationist” alternative to Darwinism. The standard story is that clear and reasonable thinking about evolution vanished for a generation— the so-called “eclipse of Darwinism”—, returning with Fisher, Haldane, Wright, et al., who showed that genetics is the missing piece of Darwin’s theory, resulting in the Modern Synthesis.
This is wrong.
The first geneticists made substantial contributions to the theory of evolution, even though history has generally not recognized their achievements. Following their critique of Darwinism (next post), the Mendelians (Bateson, Punnett, Morgan, etc.) synthesized genetics with natural selection, laying down the foundations for later evolutionary theorizing. This post illustrates some of these developments.