Cacti look slow but evolve fast as flowers reshape drives new species at surprising pace

Flower shape speed, not flower size, drives speciation

Cacti are usually seen as slow, desert-stoic plants, yet new research finds they diversify far faster than expected. Scientists analyzing flower data from more than 750 cactus species report that flower size, even across an enormous 185-fold range, hardly predicts when new species appear. Instead, the key is how quickly cactus flowers change shape over time. The study challenges older ideas about pollinators and specialized flowers and suggests deserts may evolve rapidly too.