Biologist Rosemary Grant: ‘Evolution happens much quicker than Darwin thought’
The evolutionary expert discusses the triumphs and challenges of the groundbreaking research on Galapagos Islands finches she undertook with her husband, Peter
Studying Darwin's finches has been the life's work of the renowned British evolutionary biologists Rosemary and Peter Grant. For several months every year for 40 years, the husband-and-wife team visited the Galapagos Islands in the eastern Pacific to meticulously track the fate of thousands of finches on two small islands there. The Grants demonstrated that evolution by natural selection can be observed in the wild in real time: they were the first to see and measure it in action in nature. One Step Sideways, Three Steps Forward is Rosemary Grant's new memoir. It reflects on her far-from-straight path to becoming a biologist, living with a family on the Galapagos - for 10 years the scientists' two daughters accompanied them - and the joy of sharing ideas with her partner. Rosemary, 87, is senior research biologist, emeritus at Princeton University in New Jersey. The book comes ahead of a new edition of 40 Years of Evolution - the Grants' classic account of their study of the finches - due out later this year.
The Galapagos are famous for their unusual and unique species including giant tortoises, marine iguanas and flightless cormorants. But what's the Charles Darwin connection?
Darwin spent five weeks there in 1835 on his journey around the world, and the islands were key to solidifying the concept of evolution through natural selection [put forward in On the Origin of Species in 1859]. While there, he collected a variety of specimens of different-sized songbirds. Later, back in England, he was advised that they were all species of finch. He reasoned that their diversity in terms of body size and beak shape evolved over time as they adapted for feeding on different food sources [which vary by island]. Today we recognise 17 distinct species of Galapagos finches and there is also one on Cocos Island. We now know they all evolved from a single ancestral species in the last one to two million years - probably a small flock of finches that came over from mainland South America.