Peter and Rosemary Grant facts for kids
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Peter Raymond Grant (born October 26, 1936) and Barbara Rosemary Grant (born October 8, 1936) are British scientists who study evolution. They are professors at Princeton University. They are best known for their amazing work with Darwin's finches on Daphne Major, one of the Galápagos Islands.
Since 1973, the Grants have spent six months each year on the island. They catch, tag, and take tiny blood samples from finches. Their research has shown that natural selection can happen very quickly. It can even be seen within a single lifetime or just a few years. Before their work, many scientists, including Charles Darwin, thought natural selection was a very slow process. The Grants proved that these changes in animal groups can happen much faster.
Their work was featured in a famous book called The Beak of the Finch: A Story of Evolution in Our Time by Jonathan Weiner. This book won a special award called the Pulitzer Prize for General Nonfiction in 1995. The Grants have also received many other important awards for their discoveries. These include the Balzan Prize in 2005 and the Kyoto Prize in 2009. They also received the Royal Medal in Biology in 2017. These awards recognize their incredible studies on how evolution happens right before our eyes.
Contents
Early Life and Education
Rosemary Grant's Early Years
Barbara Rosemary Grant was born in Arnside, England in 1936. When she was young, she loved collecting plant fossils. She would compare them to plants growing today. At age 12, she read Darwin's famous book, On the Origin of Species. Even though she was told that science was a male-dominated field, she kept studying.
In 1960, she earned a degree in Zoology from the University of Edinburgh. She then studied genetics. Later, she planned to study fish populations. This plan changed when she took a biology teaching job. This is where she met Peter Grant.
Peter Grant's Early Years
Peter Raymond Grant was born in 1936 in London. During World War II, his family moved to the countryside to avoid bombings. At school, he collected plants and insects. He went to the University of Cambridge.
Later, he moved to Vancouver, British Columbia, Canada. He started working on his PhD in Zoology at the University of British Columbia. Peter met Rosemary after he began his research there. They got married a year later.
Their Amazing Research
Peter Grant's PhD research looked at how ecology (the study of how living things interact with their environment) and evolution are connected. The Grants traveled to the Tres Marias Islands off Mexico. They studied birds there. They compared the beak length and body size of birds on the islands to those on the mainland.
They found that birds on the islands often had larger beaks. This suggested they could eat a wider variety of foods. This was because of what foods were available and how many other birds were competing for them.
Studying Finches on Daphne Major
Daphne Major in the Galápagos Islands was the perfect place for the Grants to study evolution. It is a small, isolated island with no people living on it. This meant any changes to the environment were natural. The island has seasons of heavy rain and long droughts. These changes greatly affect the food available to birds. The Grants would study this for decades.
In 1973, the Grants began what they thought would be a two-year study on Daphne Major. They wanted to see how new species form. There are thirteen types of finches on the Galápagos Islands. These birds are great for studying adaptive radiation. This is when one species evolves into many different species.
Each finch species has a beak shape specific to its diet. This reflects the food available. The Grants would catch, tag, measure, and take blood samples from the finches. Their "two-year" study actually continued until 2012!
Evolution in Action: Droughts and Beak Size
In 1977, there was a severe drought. Only 24 millimeters of rain fell. Many finches died because food became scarce. The small, soft seeds disappeared, leaving only large, tough seeds. Finches with smaller beaks struggled to find food.
The next two years showed that natural selection could happen very fast. Finches with smaller beaks died off. But finches with larger beaks could eat the tough seeds and survive. They then had babies. The finch population after the 1977 drought had "measurably larger" beaks than before.
In 1981, the Grants found a finch they called "Big Bird." It was heavier and had different features. It could eat both large and small seeds, and even cactus parts. Big Bird bred with local finches. Its descendants have only mated among themselves for seven generations.
Scientists later found that Big Bird came from Española Island, far away. Its descendants, mixed with local finches, have become a new species! This was the first time scientists directly saw a new species form in the wild. Studies of their DNA showed changes in genes for beak shape and size.
Then, in 1982–1983, El Niño brought eight months of steady rain. This changed the plants on the island. Small, soft seeds became plentiful. This gave birds with smaller beaks an advantage. When another drought hit, small-beaked finches could eat all the small seeds faster.
In 2003, another drought hit. By this time, a large ground finch (Geospiza magnirostris) had moved to the island. This large finch eats similar foods to the medium ground finch (G. fortis). After the 2003 drought, the medium ground finch population had smaller beaks on average. This was the opposite of what happened in 1977! The Grants thought this was because the large ground finches were competing for big seeds. So, the smaller-beaked medium ground finches had an advantage because they didn't compete as much for the large seeds. This is an example of character displacement, where species change to reduce competition.
Key Discoveries
The Grants' 40-year study taught us three big lessons about evolution:
- Natural selection is always changing: By studying the island in both wet and dry times, the Grants showed that natural selection is not a steady process. It changes depending on the environment.
- Evolution can be fast: It doesn't take millions of years. Changes in populations can be seen in just a few years.
- Selection can switch directions: In some years, large beaks are better. In other years, small beaks are better. This means that the average beak and body size of the finches kept changing. They never stayed the same over the decades.
The Grants showed that they could directly watch finch species evolve. This happened because of the changing and tough environment on Daphne Major.
Awards and Recognition
The Grants have received many important awards for their work.
Peter Grant
- Fellow of the Royal Society (UK)
- Royal Society of Canada
- American Academy of Arts and Sciences
- American Academy of Sciences
- Honorary Doctorates from Uppsala University (Sweden), Universidad San Francisco (Ecuador), University of Zurich (Switzerland), and University of Toronto (Canada).
Rosemary Grant
- Fellow of the Royal Society (UK)
- Royal Society of Canada
- American Academy of Arts and Sciences
- Honorary Doctorates from McGill University (Canada), Universidad San Francisco (Ecuador), University of Zurich (Switzerland), and University of Toronto (Canada).
- The Society for the Study of Evolution has an award named after her, the Rosemary Grant Graduate Student Research Award. It helps young scientists with their research.
Awards Received Together
- 2017 Royal Medal, Royal Society
- 2009 Kyoto Prize, Inamori Foundation
- 2009 Darwin-Wallace Medal, Linnean Society of London
- 2005 Balzan Prize for Population Biology
- 2002 Darwin Medal, Royal Society
- 1994 Leidy Medal, Academy of Natural Sciences of Philadelphia
Books
- Grant, Peter R (2023). Enchanted by Daphne: The Life of an Evolutionary Naturalist. This book tells Peter Grant's story.
The Grants' work was the main topic of the book The Beak of the Finch: A Story of Evolution in Our Time by Jonathan Weiner, which won the Pulitzer Prize for General Nonfiction in 1995.
