Scientists have uncovered how a group of Galápagos plants evolved distinct leaf shapes in real time, providing direct genetic proof of Darwin’s theories. The study shows that Scalesia, a genus of daisy-like species, developed specialized leaves within 100 years to survive on different islands.
Researchers sequenced genomes of 12 Scalesia species and found mutations in MYB1 and TCP4 genes linked to leaf development. These changes occurred after the plants arrived on the islands 300,000 years ago. The team, led by the University of Uppsala, compared leaf shapes across four islands where rainfall varies from 200 mm to 2,000 mm annually.
On dry islands, plants grew thick, fleshy leaves to store water. In wetter areas, leaves became thin and broad to capture sunlight. The genetic data matched these physical adaptations, proving evolution can be observed in short timeframes.
The findings challenge the idea that evolution requires millennia. Instead, rapid genetic shifts allowed Scalesia to diversify faster than expected. This work follows earlier studies on Darwin’s finches, which showed similar quick adaptations in birds.
The study appears in the journal Nature Ecology & Evolution. It suggests island ecosystems may be ideal labs for tracking genetic change.
Source: norwegianscitechnews.com