Nature’s palette and the evolution of colouration were the key themes of this year’s prestigious Sir Ernst Chain lecture.

The annual lecture, commemorating the achievements of Sir Ernst Chain, has become one of the most prestigious events in Imperial’s calendar. For 2022, an ecological and evolutionary theme was chosen, marking the 75th anniversary of the acquisition of Silwood Park, Imperial's key campus for these disciplines.

The event began with introductions from Imperial's Provost, Professor Ian Walmsley and Professor Guy Woodward, Deputy Head of Department, Life Sciences. The audience were then shown a short promotional film about Silwood Park.  

Professor Hopi Hoekstra, renowned evolutionary biologist from Harvard University, was the invited speaker, delivering an enthralling lecture about the evolution of colour variation in the wild. She gave her talk to a crowded lecture theatre, with a full range of attendees including expert researchers, staff and students from throughout College, VIP guests and schoolchildren.

"It was a pleasure to share what we know about how and why the tremendous diversity of the colour that we observe in the natural world - from showy feathers to camouflaging fur - has evolved" Professor Hopi Hoekstra

Professor Hoekstra started by explaining Darwin’s theory of evolution by natural selection – the original motivation for her work. She then showed how this linked to the discovery of DNA as the molecular basis of inheritance, which tells us the mechanistic details of how the diversity of living creatures evolved.

Motivated by these discoveries, Professor Hoekstra’s group seek to understand how diversity (in morphology and behaviour) arises and is maintained in nature. Specifically, they are interested in the molecular, genetic and developmental mechanisms responsible for the phenotypic variation that affects fitness: the ability of organisms to survive and reproduce in the wild.

Professor Hoekstra explained how colour is one of the most diverse characteristics of organisms, and often varies between closely related species, or even within species. Colour is of the primary ways in which organisms interact with their environment. It is used in a variety of biological processes including mate choice, warning coloration, mimicry, and crypsis. And even a small difference in colour can have dramatic effects on fitness.

She told the audience that not only is colour ecologically relevant, but we have learned a lot about the genes and pathways involved in mammalian pigmentation based on over 100 years of study by geneticists, who have cloned genes responsible for spontaneous mutations that have arisen in laboratory colonies of mice. This rich history affords us a wealth of candidate genes and an understanding of the roles of these genes in developmental pathways. 

Professor Hoekstra went on to talk about the work with mice that her group is doing to identify the precise genetic changes responsible for adaptive colour variation, and specifically how these changes through developmental mechanisms, produce variations in phenotype. 

And finally, she told us about her work on the coast of Florida, looking at natural populations of mice to understand precisely how these traits evolved in the wild. 

Professor Hoekstra said: ‘What a great honour to be invited to deliver the Sir Ernst Chain Lecture and help celebrate the 75th Anniversary of Silwood Park.  It was a pleasure to share what we know about how and why the tremendous diversity of the colour that we observe in the natural world - from showy feathers to camouflaging fur - has evolved.’

The talk was followed by a lively Q&A session led by Professor Richard Craster, Dean of the Faculty of Natural Sciences and a vote of thanks from Professor Vincent Savolainen, Director of the Georgina Mace Centre for the Living Planet.

Professor Savolainen said: ‘Hopi's talk on 'Nature's colour palette' was exceptional, from the clarity of her explanations to the outstanding science she described. She showed very elegantly why and how colour evolves in animals: from the role of the environment and natural selection to its genetic underpinning.’

You can watch the whole lecture in the video above.

Silwood 75^th Anniversary comes to South Kensington

2022 marks the 75th anniversary of Silwood Park at Imperial College London. Silwood has celebrated this milestone with a variety of exciting events and activities over the coming months, showcasing the unique history, culture and achievements of the campus, as well as looking ahead at what the future might hold.

Following the Sir Ernst Chain lecture, attendees were treated to a private view of a specially curated Silwood 75th Anniversary exhibition in the College Main Entrance. The exhibition was available for all to see from 21-27 November.

"Life Sciences at Imperial builds on a powerful legacy and has made some very important contributions to science. We look forward to an equally strong future, helping us to address some of the key challenges we face as a society." Professor Ian Walmsley Provost

The Provost, Professor Ian Walmsley, said: ‘Life Sciences at Imperial builds on a powerful legacy and has made some very important contributions to science.

We celebrated the 75th anniversary through the Sir Ernst Chain Lecture by Professor Hopi Hoekstra, Harvard University, and we look forward to an equally strong future, helping uncover mechanisms of life and helping us to address some of the key challenges we face as a society.’

Professor Guy Woodward, said: ‘It was a fantastic event and seeing Imperial's campuses coming together in South Kensington was especially pleasing - with Silwood signing off this year's cycle of 75th Anniversary events with this very special roadshow visit to the “Big Smoke” for the Sir Ernst Chain lecture. It was a great opportunity for our staff, students, alumni and members of the public to mingle in person once again, and Hopi's amazing talk on “Nature's Palette” was the perfect centrepiece for the evening.’