Evolution doesn't always take millions of years—sometimes it happens in one massive genetic leap.
The standard 'slow and steady' view of evolution suggests species change through thousands of tiny, gradual mutations. But when researchers looked at how Petunias switched from being pollinated by moths to being pollinated by bees, they found it was driven by just a few 'large-effect' genes. This is a rare, concrete example of evolution making a 'leap' rather than a crawl. It shows that major biological shifts can happen much faster and more dramatically than we ever imagined. For us, this means the tree of life is full of sudden shortcuts that can transform an organism almost overnight. It changes how we think about the speed and predictability of life on Earth.
From Hawkmoths to Bees: Reconstruction of Speciation by Modification of Major Effect Gene
SSRN · 6570548
Reproductive isolation within and between populations was conventionally thought to proceed gradually through many mutations of small phenotypic effect. Contrary to this, recent theory predicts that large-effect mutations become plausible when populations are far from their phenotypic optimum. Changes in pollinator assemblage severely compromise the reproductive success of many angiosperms, creating conditions conducive to mutations of large phenotypic effect. Here, we explore the role of major-