Museum highlights: Charles Darwin
Both behind the scenes and on display in the galleries, you'll find many specimens collected by Charles Darwin's on the five-year voyage of HMS Beagle.
Take a closer look at nine highlights from the Museum's collections, including Darwin's favourite octopus and a rare first edition of his book, On the Origin of Species.
1. Under the sea
While on HMS Beagle, Darwin proposed a theory of how coral reefs and atolls formed. He suggested that atolls originally grew around extinct volcanoes which then sank into the sea, leaving the reef an isolated circle.
Some of his specimens are now cared for at the Museum, including this Porites coral collected from the Cocos (Keeling) Islands in the Indian Ocean.
2. Layers of Time
In 1832, HMS Beagle arrived near the Cape Verde island of Santiago (then called St Jago). This is where Darwin put into practice what he'd learnt from geologist Charles Lyell's work around slow-occurring geology.
A few years later, after experiencing a strong earthquake in Chile, Dawrin realised that the raised shell beds looked similar to the layers of marine fossils observed on the cliffs of the islands of Cape Verde. He explained that it was possible that small, vertical movements from earthquakes could form mountains such as the Andes.
An example of this can be seen in the form of an ammonite clock in the From the Beginning gallery.
The shells in this specimen drawer were collected by Charles Darwin during the voyage of HMS Beagle.
While Darwin's shells aren't on display, you can see other examples of fossilised shells in the Fossils from Britain gallery.
3. A star in a jar
One of the first things Darwin collected can fit in the palm of your hand: a small but distinguished member of the 22-million-strong spirit collection.
This common octopus, (Octopus vulgaris), was collected in 1832 off the Cape Verde islands. You can see Darwin's favourite octopus, along with a number of type specimens that he collected, on a behind-the-scenes spirit collection tour.
4. A puzzling platypus
Darwin visited Australia during early 1836. He saw a number of platypuses and was fascinated by their features and behaviours, noting they were similar to European water rats.
When the first platypus skin was sent back to Europe, it was thought to be a hoax - a strange animal created by stitching a duck's bill to the body of a mole. But despite its unusual features, it is perfectly adapted to its environment.
While the type specimen is not on display, you can see another platypus in the Mammals gallery. Notice its tail - the same shape as a beaver's - and its furry, otter-like body.
5. Instant bestseller
Charles Darwin's On the Origin of Species is arguably the most important book in biology - after all, it's where he describes his theory of evolution by natural selection. Its success may have been in part thanks to the conversational rather than academic writing style.
A rare first edition, published in 1859, is on display in the Treasures gallery.
The Museum's Library holds the world's largest concentration of Darwin works. It has 478 editions of On the Origin of Species in 38 languages, including Braille.
6. Hatching a theory
Galápagos finches, commonly known as Darwin's finches, are the best-known species from Darwin's work, often credited as the inspiration for his ideas on evolution.
But as famous as these finches may be, even more significant to his research were pigeons.
Darwin bred pigeons in his garden as an experiment. By crossing birds with different characteristics, he could generate different offspring. By artificially selecting in this way, he gathered valuable evidence for his theory of evolution by natural selection.
The majority of the Museum's collections of Darwin's finches and pigeons are currently part of the ornithology (bird) collections kept at the Natural History Museum at Tring, Hertfordshire.
A few of Darwin's pigeons are on display in the Treasures gallery in London.
7. What was Toxodon?
Discovered by Darwin in present-day Uruguay, the skull of Toxodon platensis, belonged to a giant, extinct species of mammal.
It's estimated to have weighed more than a tonne and was probably similar in size to the American bison or African black rhino.
Darwin was thrilled at the idea of this 'rhinoceros-sized rodent' and regarded it as one of the most valuable finds of his voyage.
The Toxodon specimens in the Museum collection range from one centimetre to one metre. Due to their delicate nature, public access to the specimens has been restricted, so scientists are working on creating 3D versions.
8. The great beast from America
While aboard HMS Beagle, Darwin found a skull of a Megatherium, an extinct ground sloth, on the Argentinian coast near Buenos Aires.
Megatherium americanum (meaning 'great beast from America') measured up to 10 times the size of living sloths and weighed up to four tonnes (similar to a present-day bull elephant).
On its hind legs, M. americanum would have stood a full 3.5 metres (12 feet) tall.
Two halves of a Megatherium skull are the latest fossils to be digitised from Darwin's fossil mammal collection.
9. Say hello to Darwin
Before you leave, make sure to pay a visit to Darwin on the main staircase in Hintze Hall. The commanding statue was unveiled in 1885, four years after the Museum opened.