Experiments on Plant Hybridization
Gregor Mendel · 1866
"Traits are passed from parent to offspring as discrete, countable units — not as a smooth blend of parental characteristics — following statistical ratios predictable enough that Mendel derived the basic laws of inheritance from pea plants alone, decades before genes or DNA were known to exist."
An Augustinian friar spent eight years cross-breeding pea plants in a monastery garden and, without knowing what a gene physically was, worked out the mathematical rules of inheritance that genetics is still built on.
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Nothing in Biology Makes Sense Except in the Light of Evolution
"By the mid-20th century, genetics (Mendel's discrete units) and natural selection (Darwin's mechanism) had been fused into a single coherent framework — the Modern Synthesis — that made evolutionary theory the organizing principle underneath every other branch of biology."