Charles Darwin and the HMS Beagle

darwin.jpg (21170 bytes)Charles Darwin was a man who found himself at the right place at the right time or the wrong place at the wrong time, depending on how you look at it. While he suffered seasickness and intestinal parasites (Chagas' disease) that would weaken his health for the rest of his life, he certainly considered his voyage as the most important thing that ever happened to him.

The voyage of the HMS Beagle and Darwin's collections, observations and publications related to its five-year journey have perhaps affected human thinking in ways that no other scientific discoveries have. His Origin of Species and Descent of Man placed humans right smack in the middle of the animal world, at the top, perhaps, but there unmistakably. Not only did his ideas clash with theological and scientific thinking at the time, they made people uncomfortable. The thought that humans could be derived from primates didn't (and still doesn't) sit well with many people. (We can't be animals, can we?)

In the years since Darwin's seminal publications, scientists have mounted a considerable body of evidence to support the theory of evolution.  Nonetheless, if you have any doubts as to your thinking about the evidence for evolution, I would encourage you to examine some of the creationist/evolutionist web sites (on both sides of the issue) and determine for yourself.

What you should be able to distinguish within these debates is the difference between evolution itself (a gradual change in species with time) and the mechanisms of evolution (natural selection, kin selection, group selection, etc.). These are two different lines of scientific inquiry. That evolution has occurred on our planet would be very difficult to argue against, based on a considerable amount of fossil, zoological and molecular evidence. How evolution occurs (whether it occurs by some rational process or divine intervention) is where most of the debate is focused. Scientists believe that many different mechanisms of evolution occur rather than a single mechanism (i.e. survival of the fittest). And because people perceive this area of evolutionary research as the weakest (in terms of scientific evidence), that is where they usually attack.

I mention this controversy here to acknowledge its importance and to make you more comfortable thinking about evolution. We will study a little evolution when we examine marine organisms, including whales. However, this section here concerns itself with a man and a voyage and how the time he spent at sea fashioned his thinking.

Darwin, like many students, finished a BA at Cambridge at the age of 22, but really didn't know what to do with himself after that. Originally, he wanted to be a doctor like his father but the sight of blood made him squeamish so he abandoned that idea. It's interesting to note that even before Darwin left for sea there were signs that he had a weak stomach. He thought about becoming a country pastor because he would allow him to spend time outdoors studying natural history, something he loved to do. His favorite botany professor, John Henslow, was a pastor and so Darwin made plans to pursue a life in the clergy.

His heart really wasn't in it but he had a summer to think about it so he went on vacation. When he returned home, he found two letters waiting for him: one, an offer to work as a naturalist aboard the HMS Beagle, and the other, a letter from Professor Henslow encouraging him to do so. However, like many young men and women still living at home, Darwin had to consider what his father. Dr. Robert Darwin, might think about such an expedition. Darwin wrote back to Henslow:

As far as my own mind is concerned, I should, I think, certainly most gladly have accepted the opportunity, which you so kindly have offered me. But my Father, although he does not decidedly refuse me, gives such strong advice against going..that I should not be comfortable, if I did not follow it.

Darwin confessed his dilemma to Uncle Josiah, who recommended that he make a list of his father's objections and then answer them one by one. Darwin's list of his father's objections is classic:

  1. disreputable to my character as a Clergyman hereafter
  2. a wild scheme
  3. that they must have offered it to many others before me, the place of Naturalist
  4. from its not being accepted there must be some serious objection to the vessel or expedition
  5. that I should never settle down to a steady life hereafter
  6. that my accommodations would be most uncomfortable
  7. that you should consider it as again changing my profession
  8. that it would be a useless undertaking

Sound familiar? My dad once suggested that I pursue a career as a doctor or a lawyer rather than as an oceanographer so I can relate.

However the debate between Darwin and his father transpired, it's pretty clear who eventually won. Darwin was soon signed on as ship's naturalist. What's interesting is that two other naturalists had declined the position before it was offered to Darwin and the position was unpaid. In addition, Dr. Darwin had to put up 30 pounds a year for Charles' food and pay to equip him for the voyage, which probably didn't make the doctor any happier. But dad came through in the end.

beaglesm.jpg (6895 bytes)The primary mission of the Beagle was to map the coastline of southern South America and take oceanographic measurements (currents, bathymetry, etc) as well. Darwin's job as ship's naturalist was to observe everything, write it all down and collect as many specimens as possible. It was his job to record the weather, geological features, plants, animals, fossils, rocks, minerals, indigenous people and anything else that he saw. Specimens had to be packed and labeled very carefully. In preparing for the voyage, Darwin made a list of things that he would need, including 12 new shirts and other clothing; slippers; light walking shoes; a folding, portable dissecting microscope; a geological compass; a case of pistols and a rifle; a Spanish-English dictionary; a book on taxidermy; reading material (Humboldt and Milton); his favorite geology text, Lyell's Principles of Geology; a Bible; a pair of binoculars; a magnifying glass; and jars of "Spirit" (probably alcohol) for preserving specimens. (I wonder what his dad thought of that list...Thanks, Dad!)

Like any expedition, there were space limitations. The Beagle was not an exceptionally large vessel by any means. Measuring only ninety feet in length, she carried a crew of 74 people, "including the Captain, three officers, the crew, a doctor, an artist, and the naturalist. Darwin shared the poop cabin (at the back of the ship) with two officers. Their space was so cramped that Darwin had to remove a drawer each night so that he would have room for his feet."

David Likely tells the story of how the ship's Captain Robert Fitzroy almost refused to let Darwin sail because his nose did not appear to be that of a man with character. Darwin had to get testimonials that he was suitable for dining at the Captain's dinner table. Apparently, Darwin and the Captain, a fundamentalist Christian, didn't always see eye to eye (Darwin was once banned from the dinner table for several days), which has led some to speculate that this relationship even further hardened Darwin against religion.

After more than two months delay (the ship was to leave October 24, 1831), the ship attempted a departure on December 10 but ran into bad weather. Finally, on December 27 at 2:00 pm, Darwin and the Beagle left Plymouth harbor on what was to become most revolutionary oceanographic expedition of our time.

Immediately upon sailing, Darwin's enthusiasm for the voyage was severely dampened by sea-sickness. He writes:

"...the misery I endured from sea sickness is far beyond what I ever guessed at. The real misery only begins when you are so exhausted that a little exertion makes a feeling faintness come on -- I found that nothing but lying in my hammock did any good.

Three and a half weeks later, on January 16 1832, they reached the Cape Verde Islands off the coast of south Africa. It was here that Darwin's innate ability to observe in great detail and think "large" began to assert itself. In St. Jago, he correctly surmised the African origins of dust that created the hazy atmosphere of the islands, he wrote about "reckless destruction" of the forests and offered the following observations on octopus:

I was much interested by watching the habits of an Octopus, or cuttle-fish. By means of their long arms and suckers, they could drag their bodies into very narrow crevices; and, when thus fixed, it required great force to remove them. These animals escape detection by a very extraordinary, chameleon-like power of changing their color. They appear to vary their tints according to the nature of the ground over which they pass. These changes were affected in such a manner that clouds, varying in tint were continually passing over the body. Any part, being subjected to a slight shock, became almost black.

While not the first to observe cephalopod chromatophores, the detail with which he describes them belies his fascination with nature. Indeed, the enthusiasm with which he carried out his observations and collections can be found in his diary entries upon exploring South America:

I have been wandering by myself in the Brazilian forest: amongst the multitude it is hard to say what set of objects is most striking; the general luxuriance of the vegetation bears the victory, the elegance of the grasses, the novelty of the parasitical plants, the beauty of the flowers, the glossy green of the foliage, all tend to this end...To a person fond of Natural History such a day brings with it pleasure more acute than he ever may again experience" [Barlow 1933: 39-40]. And the next day, "I can only add rapture s to the former raptures" [Barlow 1933: 40].[Journal of Syms Covington, Darwin's assistant]

Overtaken with such "treasures", Darwin felt that he needed an assistant. He got permission to hire Syms Covington, the ship's "fiddler and boy to the poop cabin" [where the officers lived], who helped with the time-consuming task of cataloguing and shipping Darwin's specimens. Covington kept his own journal [Journal of Syms Covington] which offers interesting reading about Darwin and his relationship with others on board.

Many excellent accounts of Darwin's work and his own publications (Origin of Species, The Voyage of the Beagle, Descent of Man) can be found on the WWW and elsewhere and it's not my intention to summarize them here. Rather, I would like to mention a couple of his major contributions to oceanography and use it as an example of the brilliant means by which Darwin synthesized his observations.

Among Darwin's many marine biological observations, Darwin had an opportunity to study coral fringing reefs, barrier reefs and atolls in 1836 while in the Indian Ocean. Fringing reefs are coral reefs that encircle an island and atolls are "rings" of coral with a lagoon in the middle. Darwin was intrigued by the formation of atolls and their resemblance to fringing reefs surrounding volcanic islands. An avid student of geology (he was engrossed by Lyell's Princinple of Geology), Darwin postulated that atolls represent a latter stage of volcanic island development where the island sinks into the ocean over time. As the island sinks, the corals continue to grow around the fringe of the island until the island disappears leaving only the corals, a "perfect atoll", as he calls it. In his treatise on the theory of atoll formation published in Voyage of the Beagle, Darwin writes:

atollformation.gif (5524 bytes)Now as the island sinks down, either a few feet at a time or quite insensibly, we may safely infer from what is known of the conditions favorable to the growth of coral, that the living masses, bathed by the surf on the margin of the reef, will soon regain the surface. The water however, will encroach little by little on the shore, the island becoming lower and smaller, and the space between the inner edge of the reef and the beach proportionally broader...We can now at once see why encircling barrier-reefs stand so far from the shores which they front. We can also perceive, that a line drawn perpendicularly down from the outer edge of the new reef, to the foundation of solid rock beneath the old fringing-reef, will exceed by as many feet as there have been feet of subsidence, that small limit of depth at which the effective corals can live: -- the little architects having built up their great wall-like mass, as the whole sank down, upon a basis formed of other corals and their consolidated fragments...As the barrier-reef slowly sinks down, the corals will go on vigorously growing upwards; but as the islands sinks, the water will gain inch by inch on the shore -- the separate mountains first forming separate islands within one great reef -- and finally, the last and highest pinnacle disappearing. The instant this takes place, a perfect atoll is formed...

Many decades later (I'm looking for the original reference), geologists took cores of an atoll and confirmed their volcanic origins, just as Darwin described. In addition, Darwin's classification scheme of tropical corals reefs--fringing reefs, barrier reefs and atolls--is still used today.

One additional and little known synthesis provided by Darwin concerns the theory of plate tectonics. While in South America, Darwin had a chance to explore the Andes and hike in the mountains. His observations of sea shells at some elevation in the Andes intrigued him and he postulated vast tectonic movements that would remain in obscurity for at least a century. In The Voyage of the Beagle, he writes: 

The Beagle anchored late at night in the bay of Valparaiso, the chief seaport of Chile. When morning came, everything appeared delightful. After Tierra del Fuego, the climate felt quite delicious -- the atmosphere so dry, and the heavens so clear and blue with the sun shining brightly, that all nature seemed sparkling with life.

My object in coming here was to see the great beds of shells, which stand some yards above the level of the sea, and are burnt for lime. The proofs of the elevation of this whole line of coast are unequivocal: at the height of a few hundred feet old-looking shells are numerous, and I found some at 1300 feet. These shells either lie loose on the surface, or are embedded in a reddish-black vegetable mould. I was much surprised to find under the microscope that this vegetable mould is really marine mud, full of minute particles of organic bodies.

We spent the day on the summit, and I never enjoyed one more thoroughly. Chile, bounded by the Andes and the Pacific, was seen as in a map. The pleasure from the scenery, in itself beautiful, was heightened by the many reflections which arose from the mere view of the Campana range with its lesser parallel ones, and of the broad valley of Quillota directly intersecting them. Who can avoid wondering at the force which has upheaved these mountains, and even more so at the countless ages which it must have required to have broken through, removed, and levelled whole masses of them? It is well in this case to call to mind the vast shingle and sedimentary beds of Patagonia, which, if heaped on the Cordillera, would increase its height by so many thousand feet. When in that country, I wondered how any mountain-chain could have supplied such masses, and not have been utterly obliterated. We must not now reverse the wonder, and doubt whether all-powerful time can grind down mountains -- even the gigantic Cordillera -- into-gravel and mud. [Chapter 12, Central Chile, Voyage of the Beagle Online]

atollst.gif (11331 bytes)The theory of plate tectonic of which Darwin had the first inklings and the theory of atoll formation, which stands bascially in the same form today as that which Darwin proposed, illustrates Darwin's ability to take bits and pieces of information and put them together in some sort of rational explanation. His vast knowledge of the science of the times, including the work of Lyell, Lamarck, Malthus, Humboldt and other scientists likely represents a deep desire to understand the world around him. His interests in theology may have come from such an interest, to understand the nature of the Universe and all that was in it. Using the tools of science and a talent for observation, Darwin provided a vast storehouse of natural history observations, which alone would have been worthy of fame. But not content with mere observations, Darwin spent the next twenty years pondering and discussing what he had found. And the result of those ponderments and discussions were three publications that provide the cornerstone for evolutionary theory today.

Professor George P. Landow in the Department of English and Art History at Brown University summarizes what he considers to be the major impacts of Darwin's work on nineteenth-century thinking:

  1. That biological types or species do not have a fixed, static existence but exist in permanent states of change and flux;
  2. that all life, biologically considered, takes the form of a struggle to exist -- more exactly, to exist and produce the greatest number of offspring;
  3. that this struggle for existence culls out those organisms less well adapted to any particular ecology and allows those better adapted to flourish -- a process called Natural Selection;
  4. that natural selection, development, and evolution requires enormously long periods of time, so long, in fact, that the everyday experience of human beings provides them with no ability to interpret such histories;
  5. that the genetic variations ultimately producing increased survivability are random and not caused (as religious thinkers would have it) by God or (as Lammarck would have it) by the organism's own striving for perfection.[]

As Landow puts it: "The effect of all these points was to move man away from the center of creation and imply that he could hardly be its crowning glory."

While Darwin probably would not consider himself an oceanographer, it was, after all, the sea that allowed him to carry out his set of observations that would revolutionize nineteenth-century thinking. And it was a most interesting and fortuitous set of islands, the Galapagos Islands, that provided an ideal natural laboratory in which theories of natural selection could be tested. He circumnavigated the globe, seasick most of the way, and brought home a treasure chest on natural observations. On that basis, I submit to you that Darwin was an oceanographer!

On October 2, 1836, Darwin left the Beagle after a voyage of five years, thankful to be home and yet to reap the rewards of his labors. In 1859, he published Origin of Species and the rest is history, as they say.

Note on HMS Beagle figure: The illustration above is a detail from a watercolor of H.M.S. Beagle in the Murray Narrows, a passage in the straits around Tierra del Fuego. In fact, it's in Darwin Channel, named by Captain FitzRoy in honor of Charles Darwin. The painting is by Conrad Martens, ship's artist.

Note on atoll image: This chain of coral-fringed islands forms the Leeward Island chain within the French Society Islands. At bottom right are the islands of Tahaa and Raiatea. They are old, eroded volcanoes, fringed by a coral reef. Northward along the chain, the original central volcanoes are older and more heavily eroded. On Bora Bora (center), the reef is prominently developed and the island significantly eroded. The northernmost island, Tupai, is merely an atoll, having lost any relic of the volcano around which the reef originally grew, except for the shallow floor of the lagoon, showing up in turquoise.

Cool links

Charles Darwin and the Beagle: Selected Essays
Great overview of Darwin's voyage by David Likely

Darwin and Evolution Overview, Brown University

Charles Darwin's texts online: Voyage of the Beagle, Origin of Species, the Descent of Man

Origin of Species Online

Voyage of the Beagle Online

Voyage of the Beagle

Journal of Syms Covington, Darwin's assistant

From Primordial Soup to the Prebiotic Beach, an interview with Stanley Miller, UC San Diego

Tutorial on the Voyage of the Beagle

The BioZone: Evolution

The Creation/Evolution Controversy
A sane and salient treatment that should reconcile both sides

Sea Vents: Where Life Began

Charles Darwin Research Station in the Galapagos Islands

Bikini Atoll: site of nuclear testing in the 40s and 50s and the home of the bikini