Leonard Jenyns was an important 19th century naturalist. He lived in Cambridgeshire for much of his life, making observations and collecting specimens from the local area. Jenyns also knew many other key naturalists of the day, including Charles Darwin and John Stevens Henslow, who became his brother-in-law. A large part of Jenyns’ collection is now housed here in the Museum and offers a fascinating snapshot of Cambridgeshire 200 years ago, before the last extensive wetland areas in the county were drained.

In 1831 Jenyns was offered the chance to accompany Captain Robert Fitzroy on board HMS Beagle, for a round-the-world trip of discovery. Existing commitments meant that Jenyns declined the offer, but recommended his young friend Charles Darwin instead.  Jenyns is reported to have later “regretted his unimaginative decision” but admitted that “no better man could have been chosen.”

Although Jenyns passed up the chance to go on the Beagle voyage, he helped to identify specimens that Darwin collected, especially the fish species, some of which can be seen on display in the Museum’s Lower Gallery.

Jenyns kept detailed notes about the specimens he collected in Cambridgeshire, which he recorded in beautiful, handwritten notebooks, archived in the Museum. Jenyns also recorded timings of natural events, such as the emergence dates of flowers and insects, and arrival dates of migratory birds. This information now forms an invaluable baseline for evaluating the effects of environmental change, as it allows researchers to catalogue changes in species that have occurred over the last 200 years as a result of agricultural intensification and global warming. Such information is important for informing modern conservation efforts to restore the diverse ecology of wetland habitats.