Darwin would have enjoyed these

Goose barnacle, Pollicipes comucopia
Goose barnacle, Pollicipes comucopia

We are currently sailing around Spain in our boat for much of the year and on entering La Corona in northern Spain we encountered many small boats from which men were leaning somewhat precariously scraping hard at the rocks underneath with long poles. We were mystified until we saw a strange shellfish for sale in the market and restaurants. These we learnt were ‘percebes’ (pronounced ‘perthebes’) or goose-neck barnacles in English. They are also known as “pousse-pieds” in France and the scientific name is Pollicipes comucopia. We were looking forward to trying this new delicacy and had our first taste in a local restaurant. At 80-100 euros a kilo they are even more expensive than lobster or crab, but delicious. I was extremely curious and had a small dissecting session during the meal. The barnacle does indeed look like a goose’s head with beak on a stalk. The whole structure is about 3-5 cm long (the longer the better) and after carefully splitting the beak open I found a tiny creature like a shrimp which is suspended in the beak with its feathery legs which wave in the air to catch food when alive.

This is attached to a rock by the interesting part (for gourmets) which is a column of soft pink ‘flesh’ which you detach by twisting and pulling from the beak and eat, giving the barnacle the classification of a ‘stalked’ barnacle as opposed to a conical one.

Now what has all this to do with Darwin and not Mrs Beeton, you may be wondering. It may not be very well known but as well as producing a theory of “descent with modification by natural selection” as his theory of evolution was first described, Darwin was an avid and experienced researcher into natural history of all kinds. He made a large collection of plants, birds, vertebrates, amphibians, crustaceans etc while travelling on the Beagle. He also described the Andes, studied glaciers and coral reefs, producing a theory of the formation of coral islands and reefs and discussing his own geological theories with Charles Lyell. He could continue research into any subject that took his fancy because of an independent income provided by his family. Not for him the competitive thrust to obtain an income as a university professor or a museum creator.

After his return from the Beagle voyage in 1836 Darwin married in 1839 and eventually settled down to the life of a country gentleman scientist in Down House, Kent where he lived for the rest of his life. In 1844 he entrusted his first written thoughts about his theory to a few selected friends because he did not think that the time was ripe to introduce such a revolutionary theory. He was stunned when a book Vestiges of the Natural History of Creation by Robert Chambers was published in the same year which used the same sort of evidence that Darwin was still collecting to produce a theory very much like his own. The book became a best seller but was ridiculed by the scientific community because Chambers wrote more in the style of a journalist and was not an established naturalist. In spite of already being a published naturalist, a fellow of the Royal Society and the Zoological Society of London, Darwin realised that he would have to establish an unchallenged reputation as a naturalist by studying a particular organism in great detail before anybody would take his theory seriously. Many organisms were already ‘bagged’ for study by his contemporaries and so he decided to expand on an interest that had been awakened during his Beagle voyage. His choice fell on barnacles. These were sent by post for him to study from collections all over the world and for a study that was expected to last 2-3 years, it eventually took him 8 years to produce his book A Monograph of the fossil Cirripedia (barnacles to you and me) in 1854.

Filled with the acclaim accorded to him after the publication of this work, Darwin now began to write a detailed book about his theory, his nervous anxieties about his ‘child’ causing him to perform many more experiments and accumulate copious evidence. He was again anticipated by Alfred Russel Wallace who sent Darwin a small package in 1858 containing an essay for Darwin’s comments. This essay exactly described the theory that Darwin was working on and he and Wallace presented a joint paper to the Linnean Society, though neither was present and the paper was read by the secretary. In 1859, Darwin finally presented his new theory to the world as The Origin of Species by Natural Selection and the ‘rest is history’. Still he carried on with his researches into natural history and found the time and energy to produce books about plants and the fertilisation of orchids by insects and even some psychology about man.

To return to my own encounter with the barnacles. At the time that I was enjoying my first taste of percebes, I happened to be reading Darwin and the Barnacle by Rebecca Stott. I was delighted to discover that she also found them fascinating and dissected hers at the dining table. I was then stimulated into reading the biographies of Darwin by Janet Browne, Voyaging and The Power of Place. I also intend to read Reef Madness: Charles Darwin by David Dobbs as soon as I can get my hands on it.

We also visited Down House in Kent where Darwin lived and performed many of his experiments. There you see the actual study where he worked to a strict timetable in which the lives of the whole family and household revolved around him. The circular desk with all its drawers, and the stool that allowed him to pass easily from such activities as writing or microscope work are still in place, together with filing cabinets, his microscope and some notebooks. Having read these biographies, I now realise that there were not many areas of natural history that Darwin did not study. His house and garden became permanent laboratories with his children and staff recruited as laboratory assistants to help with his experiments. Any time that you encounter earthworms or climbing plants or any number of other natural phenomenon you may be sure that Darwin thought about and even studied it at some point in his lifetime. His last paper was published in the same edition of Nature as his obituary and described how he had discovered that the primroses around his garden were pecked at by birds in search of nectar. My respect for him as one of the greatest polymaths in natural history grows with more acquaintance.

Eileen Lawley

References

- Janet Browne, Voyaging (1995) and The Power of Place (2002) pub Pimlico
- Charles Darwin: Too many to list but all his writings are now available online at darwin-online.org.uk Cambridge University Library contains many of his handwritten notebooks as well as correspondence.
- David Dobbs Reef Madness: Charles Darwin, Alexander Agassiz and the Meaning of Coral (2005) pub Pantheon Books
-Rebecca Stott Darwin and the Barnacle (2003) pub Faber and Faber

To top