Galápagos Daisies Show Repeated Evolution Through Different Genes

Galápagos giant daisies, known as *Scalesia*, have repeatedly evolved similar heat-tolerant leaf shapes using different genetic mechanisms. This finding comes from an international research team that analyzed the complete genomes of all known *Scalesia* species. The plants independently developed deeply lobed leaves multiple times within their evolutionary history.

This process, known as parallel evolution, demonstrates how organisms can arrive at similar solutions to environmental challenges. The research indicates that while the physical trait of lobed leaves is the same, the underlying genetic changes producing it differ across various *Scalesia* lineages. This suggests evolution can draw on a network of interacting genes rather than a single “master gene” to achieve similar outcomes.

*Scalesia* is a relatively young genus, with all current species emerging within the last one million years. These plants have adapted to diverse habitats across the Galápagos Islands, from humid highland forests to hot, dry lowlands. The appearance of different species varies significantly, including leaf shapes ranging from large and entire to small and deeply lobed.

Scientists believe the lobed leaf shape helps plants survive dry and hot conditions. This adaptation likely limits water loss and improves heat dissipation. The study also revealed significant genetic differences among isolated populations of *Scalesia*, suggesting that new species may currently be forming. These distinct evolutionary lineages may require individual conservation management.

Professor Michael D. Martin of the Norwegian University of Science and Technology's University Museum was part of the research team. Vanessa Bieker, a researcher at the Royal Botanic Gardens, Kew, served as the first author of the publication. The findings were published in *Nature Communications*.