Friends and colleagues pay tribute after the recent deaths of these groundbreaking naturalists, who shifted our understanding of the world and our future

Over Christmas and the new year, three of the world’s leading naturalists died. Thomas Lovejoy, a conservation biologist credited with popularising the term “biodiversity” and a passionate defender of the Amazon, died on 25 December. A day later, Edward O Wilson, known to many as the “modern-day Darwin”, died in Burlington, Massachusetts. On 2 January, Richard Leakey, a world-renowned Kenyan conservationist who helped establish Africa as the birthplace of humankind, died at his home in Nairobi.

From presidents to undergraduate students, thousands have paid tribute to the three men, whose achievements range from developing theories on forest and island ecosystems to reforming the Kenyan civil service and devising proposals to protect half the planet for nature. Alongside grand accomplishments, which were sometimes controversial, their passing has been a chance to reflect on the small and the mundane: fleeting interactions that inspired careers, kind words that propelled research projects, and generosity of spirit that has helped amplify the voices of those that practise and produce science.