April 15, 2024


Plant specimens collected by Charles Darwin on the voyage of the Beagle have been found in an archive at Cambridge University.

The rare specimens, stored for almost 200 years in the archives of the Cambridge University herbarium, were given by Darwin to his teacher and friend Prof John Stevens Henslow, the founder of Cambridge University Botanic Garden.

Now they are to be revealed to the public for the first time in a Channel 5 TV documentary which explores the relationship between Darwin and Henslow.

“Henslow was a pioneer of botanical teaching and a great mentor to Darwin,” said Dr Edwin Rose, a historian of science at Cambridge. He said Darwin, who studied theology at Cambridge, took Henslow’s botanical course three times.

Henslow, a local minister, taught what was then called natural theology. “It was all about collecting examples of natural creation – ie numerous specimens of different plant species – so they could understand the wisdom of the divine creator and how God created the world,” Rose said. “This was one of the main drivers for undertaking studies of the natural world in the early 19th century.”

Amber Horning, assistant herbarium curator, Dr Lauren Gardner, curator, and Dr Edwin Rose with a selection of Darwin’s specimens, illustrations and letters. Photo: Jessica Keating / University of Cambridge

When the aristocratic captain of the Beagle, Robert Fitzroy, sought a gentleman naturalist to accompany him on his voyage in 1831, it was Henslow who, having turned down the role himself, recruited the 22-year-old Darwin for recommended the post.

Darwin then faithfully mailed plant specimens back to his old tutor, whose replies praised his work, but complain about its packagingis preserved for posterity in Cambridge University’s library.

“Anything Darwin could collect and send to Henslow was seen as an asset because Henslow was actively building the Cambridge botanical museum collection at the time,” Rose said.

It was envisioned as a “massive” teaching resource to facilitate Henslow’s pedagogical program, which sought to “understand the design of the Creator” and the infinite scope of God’s creation.

As a result, the university holds at least 1,000 specimens collected by Darwin in its herbarium, which was founded in 1761 and now consists of approximately 1.1 million plant specimens from around the world, including 50,000 “type species” – the original specimens used to describe new species.

“Almost all the plants Darwin collected that are now in the herbarium are type specimens,” Rose said. “At the time, he had a keen eye for spotting species that were new to European science. Almost everything he collected no one in England had ever seen.”

This includes a cucumber specimen collected by Darwin that is the only representative of that species known to scientists, implying that it may now be extinct.

Although the herbarium’s collection has been accessible to Cambridge scholars since its inception, it has never been open to the public and Rose said some of the specimens collected by Darwin had never been properly studied.

Curators suspect they may have lain virtually untouched in the herbarium’s vast collection since Henslow first received, identified and cataloged them, decades before Darwin published his theory of natural selection.

“There are treasures still waiting for scientists to come and explore them,” Rose said.

Opuntia Cacti specimens collected by Darwin in the Galapagos next to illustrations of the plants drawn by Henslow. Photo: Jessica Keating / University of Cambridge

One “recent find,” a specimen of lichen whose label says it was by “C. Darwin” in 1833, rests loosely on the piece of paper it’s printed on. “It’s not even mounted or glued,” Rose said. said.

Another specimen of fungal herbarium collected by Darwin in Brazil was discovered in the archive wrapped in the original newspaper Darwin used to preserve his finds on the Beagle, revealing how 19th-century botanical collecting practices in challenging, tropical, humid environments worked “when it dries out. from plants is difficult”, said Rose.

It brings scientists “just that little bit closer to the actual moments when these specimens were found, preserved and wrapped by Darwin himself,” he said.

Two seaweed specimens collected by Darwin on the coast of Tierra del Fuego in 1833 correspond to letters Darwin wrote in which he said he would never forget the “shout”. the indigenous people who live on the South American archipelago made when they saw him enter the beach.

Another “neglected” specimen featured in the Channel 5 documentary – Susan Calman’s Great British Cities, which airs next Friday – is an Opuntia (turkey) cactus.

This species was “totally unknown” to Europeans when Darwin sent it to Henslow, recording his observations of its role in the Galápagos Islands. “Darwin observed that both the lizards and the birds use it as a great reserve for food and water,” Rose said. “Understanding these broader interactions between nature – how different food chains work, but also the unique, environmental conditions that cause these animals to develop in a very specific way – laid the foundation for Darwin’s evolutionary theory.”



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