(CNN) — A set of Charles Darwin’s notebooks have been returned to Cambridge University anonymously, more than 20 years after he was reported missing.
The two notebooks — one of which includes Darwin’s famous 1837 “Tree of Life” sketch — were returned to Cambridge University Library in March 2022, the university said in a statement.
They were left outside the librarian’s office and wrapped in plastic, in a pink gift bag with a brown envelope containing a box of notebooks and an unsigned printed note.
“Librarian, Happy Easter X,” the note read.
The valuable objects, which the university thinks might be worth”millions“, were lost during a routine check in January 2001, when it was revealed that the small box containing the notebooks had not been returned to its proper place in the university’s special collections rooms.
After an “exhaustive” search that lasted years, the university officially declared the notebooks missing – and likely stolen – in November 2020.
At the time, the university launched a worldwide appeal for help finding the books.
“Relief” at the reappearance of the books
“My sense of relief at the return of the books is profound and almost impossible to express. Like many others around the world, I was heartbroken to learn of their loss. My joy at their return is immense,” he said. Dr. Jessica Gardner, a librarian at the University of Cambridge, in a statement announcing the return of the books.
“They may be tiny, the size of a postcard, but the impact of these notebooks on the history of science and their importance to our world-class collections cannot be overstated.”
“I am overjoyed to learn that the notebooks have returned safely to their rightful home,” said Professor Stephen J Toope, Vice-Chancellor of the University of Cambridge, in a statement announcing the return of the notebooks.
“Objects like these are crucial to our understanding, not just of the history of science, but of the history of mankind.”
The Cambridgeshire Police investigation into the disappearance and return of the notebook is ongoing, the statement added.
The theory of evolution
Darwin used the idea of the tree of life to contextualize the theory of evolution and show how all species on Earth are related and evolved from a common ancestor, according to the Natural History Museum in London.
His first sketch of the “Tree of Life” was drawn in the summer of 1837, a year after he returned to England from his round-the-world voyage on HMS Beagle. More than two decades later, Darwin would publish the most important book of his career, “On the Origin of Species”, where he expanded on his ideas on evolution.