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Cattleya Orchid and Three Brazilian Hummingbirds

Thus, from this war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely the production of the higher animals directly follows. There is grandeur in this view of life . . . from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.—Darwin, On the Origin of Species1(p490)

She held herself upright, and often threw her head a little backwards, as if she defied the world with her joyousness.—Darwin, memorial for Annie2(p359)

This year we commemorate the 200th anniversary of the birth of Charles Darwin (1809-1882). His foundational On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life was published in London, England, on Thursday, November 24, 1859; the first edition of 1250 copies sold out within 24 hours. A second edition of 3000 copies with corrections appeared soon afterward on January 7, 1860. There were 6 editions, each with alterations and corrections. The phrase "survival of the fittest" first appeared in the fifth edition in 1869. The sixth and final edition, issued in 1872, is titled The Origin of Species. During Darwin's lifetime, translations appeared in 11 languages.3



Martin Johnson Heade (1819-1904), American. Cattleya Orchid and Three Brazilian Hummingbirds, 1871. Oil on wood, 34.8x 45.6 cm. Courtesy of the National Gallery of Art (http://www.nga.gov), Washington, DC; gift of The Morris and Gwendolyn Cafritz Foundation. Image ©2009 Board of Trustees, National Gallery of Art.




It was in 1836 during the last months of his 5-year voyage on the Beagle that Darwin began to consolidate his thinking about the specimens he had collected on his travels. His thoughts about evolution first were set out in the following year in his "Transmutation Notebook B." The text in Figure 1 reads as follows:



Figure 1. The "I think . . . ‘tree of life’ page" from Charles Darwin's notebook B. Cambridge University Library MS.DAR.121:p36. By permission of the Syndics of Cambridge University Library, Cambridge, United Kingdom.




I think . . . Case must be made that one generation then should be as many living as now. To do this & to have many species in the same genus (as is). REQUIRES extinction. . . . Thus between A&B immense gap of relation. C&B the finest gradation, B&D rather greater distinction. Thus genera would be formed.—bearing relation [not shown in Figure] to ancient types . . . death of species . . . is consequence of non adaptation of circumstances.

He amplified this formulation in his 35-page "Pencil Sketch" of 1842 and in his 230-page essay of 1844.4 But the stimulus to publish came sooner than he planned when he received Alfred Russel Wallace's (1823-1913) essay on natural selection in 1858. Their work was read to the Linnean Society of London by its secretary on July 1, 1858, "On the Tendency of Varieties to Depart Indefinitely From the Original Type" by Wallace and an "Extract From an Unpublished Work on Species" from Darwin's essay of 1844, "On Variation of Organic Beings in a State of Nature; on the Natural Means of Selection; on the Comparison of Domestic Races and True Species," together with "Abstract of a Letter" from Darwin to Asa Gray. This was the first announcement of the Darwin-Wallace theory of evolution by natural selection. The papers appeared in print on August 20, 1858. The presentation of the papers led Darwin to write a condensed abstract of his planned "big book" on natural selection. That big book abstract was On the Origin of Species. There is only 1 figure in it, a more extensive tree of life. Neither Darwin nor Wallace was present at the Linnean Society that day. Darwin attended the funeral of his tenth child, an 18-month-old boy with an intellectual disability who died of scarlet fever.2 Wallace was in Borneo.

Darwin often was ill himself and suffered for more than 40 years from long bouts of vomiting, abdominal pain, headaches, fatigue, skin problems (eczema), and anxiety. He underwent many rest cures and took the baths at hydropathic centers.4 Many of his friends thought he had hypochondria or an anxiety disorder, as have many of his biographers. His correspondence includes 416 health-related letters, and he writes of his illness in his autobiography. One of his physicians, Edward Lane, diagnosed severe dyspepsia, a diagnosis that is consistent with inflammatory bowel disease. Crohn disease has been recently proposed as his primary diagnosis5; the typical age at its onset is 20 to 40 years. Darwin's onset was at age 30 years and followed a chronic course with worsening of his symptoms at around age 35 years. It occurred in bouts with short partial remissions. His symptoms suggest the involvement of his upper small intestine (gastroduodenal Crohn disease, a rare form) and are consistent with his upper abdominal pain, flatulence, and vomiting. Although his articular and neurological symptoms (numbness of his fingers, neuropathy) and his "extreme fatigue," low fever, and chronicity are consistent with this diagnosis, it remains speculative. Perhaps someday genetic confirmation of his illness will be possible. Crohn disease does not explain his cutaneous symptoms, lifelong emotional sensitivity, and symptoms of anxiety.

At age 30 years, Darwin married his first cousin Emma Wedgwood; there was a long history of intermarriage between the 2 families. Of 26 children born to these cousin marriages, 19 did not reproduce: 5 died prematurely, 5 remained unmarried, and 9 married but had no children.6 Knowing the risks of inbreeding, Darwin carefully observed his children; there were 10 births, the last when Emma was 48 years old, and 7 surviving children. Three children died, but the death of his 10-year-old daughter Annie had the greatest emotional impact on him and most challenged his Christian beliefs. He worried too that she had inherited her illness from him. He wrote a memorial to her [epigraph]. (It is now believed that she died of tuberculosis.) He expressed his dread about hereditary ill health in his other children.6

Largely because of Darwin's ill health, after the publication of On the Origin of Species, four friends in science spread its message3: Charles Lyell, Joseph Hooker, Gray, and Thomas Henry Huxley (Darwin's "bulldog," so adamant was he in its defense). So often ill, Darwin remained home, working in his country home in Kent, corresponding widely.

After the publication of Origin, Darwin continued his investigations throughout his lifetime; his last book, one of his most popular, was on earthworms and was published shortly before he died. After Origin, he turned next to botany to clarify evolutionary mechanisms. The book that followed Origin, On the Various Contrivances by Which British and Foreign Orchids Are Fertilized by Insects, and on the Good Effects of Intercrossing, was published May 15, 1862, the product of 10 months of intense work. It served as the first of the volumes of supporting evidence for Origin and was his first fully developed application of the theory of natural selection. Darwin wrote that during the summers of 1838 and 1839, he became interested in the cross-fertilization of flowers by insects and noted the importance of crossing in keeping forms constant. He found that cross-pollinated plants produced more fit offspring than self-pollinators and conducted thousands of crossings to prove his point. The orchid's beauty, he proposed, was not "designed by God" for human pleasure but was honed over time by natural selection to attract insect cross-pollinators. Darwin's friend Gray commented that had the Orchids book appeared first, there might have been less controversy over Origin.7(pp271-275) But he disagreed with Gould and maintained that beauty too was a result of natural selection.

Species of birds cross-pollinate flowers too. Hummingbirds in South America (they are extinct in Europe) have a particular predilection for orchids. John Gould (1804-1881), the leading 19th-century authority on hummingbirds, believed that their beauty was a sign of divine craftsmanship and a gift from God to man. He quoted John Audubon's inspiring description of the hummingbird as a "gentle fragment of a rainbow."8(p96) Gould believed that a species has distinctive and constant characters, stating that he had never observed variation and had no trouble distinguishing many species of hummingbirds. His beautiful hummingbird images soon were appropriated in public rebuttals of Darwin's theory, based on Gould's view that hummingbirds' coloring was purely ornamentation and had played no role in adaptation; beauty was for beauty's sake and its origin divine. Darwin appreciated beauty in nature and wrote that while standing in a Brazilian forest "it is not possible to give an adequate idea of the higher feelings of wonder, admiration, which fill and elevate the mind."4 But he disagreed with Gould and maintained that beauty too was a result of natural selection.

American artist Martin Johnson Heade (1819-1904) illustrated that beauty.9 From his early childhood, Heade had an "all absorbing craze" for hummingbirds and studied them with the eye of a naturalist, taming them to drink sugar water from his hand. He sought to paint every known variety of Brazilian hummingbird and sailed for Rio de Janeiro in 1863 to do so. In 1870 he began combining their portraits with tropical flowers, especially orchids, painting the birds to scale as he did the flowers. Cattleya Orchid and Three Brazilian Hummingbirds (cover) was completed in 1871 on his third trip to South America. A single cattleya is placed at center left, its furrowed pseudo bulbs that store water and minerals and its leaves shown below; it is depicted with 3 hummingbirds. The 2 birds circling above the nest are male and female amethyst woodstars (Calliphlox amethystina), native to Brazil. The brightly colored bird in the lower right, however, is a male red-tailed comet (Sappho sparganura), found only in Ecuador and Colombia. Perhaps the Colombian interloper was added so its pale green upper torso could complement the pink orchid and its red tail amplify the deep pink of the orchid. Heade creates the atmospheric effects of a primeval forest, showing the viewer that in the midst of decaying and dead matter new life is abundantly present.

This species of orchid is named after William Cattley, who experimented with orchid cultivation in 1818. His work led to their availability on a grand scale in England. Although this species grows wild in Brazil, Heade probably used a cultivated orchid for his model. Heade's paintings did not receive much notice in his lifetime but have been rediscovered. Orchids were associated with sexuality. This and the sensual quality of Heade's paintings may have contributed to Victorian lack of interest in them. The word orchid is derived from orchis, testicle (eg, cryptorchid), after the shape of the tuber at the base of the flower; some species were once considered aphrodisiacs.

For Darwin sexual attraction was an essential element in evolution. He proposed that brilliant plumage in birds served a utilitarian function by making males attractive to females. Secondary sexual characteristics throughout the animal kingdom evolved in the battle to facilitate mate selection. The theory of sexual selection occupies only a few pages in On the Origin of Species but is central to his subsequent book, The Descent of Man, where hummingbirds have a more prominent place. Darwin proposed that the human breeding of fancy pigeons is similar to what occurs with hummingbirds. Pigeons' breeding results from artificial (ie, man’s) selection while hummingbirds evolve through natural selection as females choose the more beautiful males. Wallace disagreed, focusing instead on why female plumage was dull, suggesting it is a form of camouflage to protect the female from predation. Art critic John Ruskin criticized Darwin on aesthetic grounds. He expressed concern about separating natural science from moral philosophy, believing that "the morality of aesthetics was to be found in nature, not in natural selection."8(p283) Darwin's descent with modification focused on what can be seen while Ruskin's aesthetics focused on what is unseen, the origins of the wonder that Darwin experienced in the Brazilian tropical forest.

Darwin's third major book, The Expression of Emotions in Man and Animals, is of particular interest to psychiatry.10 In it he relied heavily on photographs of mental patients to illustrate emotional expression in man. On the recommendation of Henry Maudsley he actively collaborated with James Crichton-Browne (1840-1938), who later became one of the most distinguished psychiatrists in England. Dr Crichton-Browne, the medical director of West Riding Asylum in Wakefield, supplied Darwin with detailed materials and photographs of "insane" residents. So great was his contribution that Darwin discussed coauthorship, but Browne declined.

Darwin's own emotional expression as he grew older is best illustrated by the portrait of him by John Collier (1850-1934) (Figure 2). Collier was the son-in-law of his close friend Thomas Henry Huxley. The portrait is a replica of his earlier one for the Linnean Society. Darwin's son William Erasmus believed it to be an improvement over the original. Darwin is shown in 1881, the year before he died. He faces the viewer with his customary cloak draped over his shoulders and holding in his left hand his slouch hat that he wore to keep out the cold. Darwin approved, saying it was the best of his portraits. His eyes engage the viewer and convey a kindly sense of weariness and concern.



Figure 2. John Collier (1850-1934), English. Portrait of Charles Darwin, 1883 (1881). Oil on canvas, 49 x 38 in (1257 x 965 mm). National Portrait Gallery (http://www.npg.org.uk/), London, United Kingdom/The Bridgeman Art Library. Thanks to Richard Macksey for consultation and review.




In On the Origin of Species, Darwin wrote that he used

the term Struggle for Existence in a large and metaphorical sense, including the dependence of one being on another, and including (which is more important) not only the life of the individual but success in leaving progeny.1(p62)

The Russian evolutionists placed the greater emphasis on the dependence of one being on another, emphasizing mutual aid.11 They proposed from their studies in the vastness of scarcely populated Siberia, where whole species could be eliminated in a single storm, that mutual aid was the driving force in evolution. Today we speak of the role of cooperation in evolution.12 Unlike the tropics, on sparsely populated Siberian plains populations were threatened by physical circumstances so severe that slight competitive advantage over another could easily seem insignificant.11 Thus evolution must be considered in the midst of plenty and in the midst of scarcity. Charles Sanders Peirce, father of pragmatism, suggested 3 aspects of evolution: by chance, through necessity, and through creative love among members of a species; all he believed were forces in evolution.13(pp267-300)

There was creative love in Darwin's marriage. In his autobiography, Darwin wrote lovingly about his wife, Emma, and marveled "at my good fortune that she, so infinitely my superior in every single moral quality, consented to be my wife," writing, "She has been my wise advisor and cheerful comforter throughout life."4(p80) She nursed him through his lifelong illnesses and comforted him in his bereavement, providing the support that made his creative work possible. Yet it was Emma's lifelong concern about his salvation that was most emotionally troubling. Early in their marriage, while pregnant, Emma wrote to Charles, when he was finalizing the voyage of the Beagle.4 She worried that if she died in childbirth, as had his mother when he was 8 years old, and he lacked Christian belief, he would not be saved; most importantly, they would not be reunited in the afterlife. He kept her letter with him throughout his lifetime, writing a message on the letter's edge for her to find after his death, "When I am dead, know I have kissed and cried over this many times."4(p199),14(p80)

James C. Harris, MD



REFERENCES

1. Darwin C, Costa JT. The Annotated Origin: A Facsimile of the First Edition of On the Origin of Species. Boston, MA: Belknap Press/Harvard University Press; 2009.
2. Keynes R. Darwin, His Daughter, and Human Evolution. New York, NY: Riverhead Books; 2001.
3. Browne J. Darwin's Origin of Species: A Biography. London, UK: Atlantic Books/Grove Atlantic; 2006.
4. Darwin C. The Autobiography of Charles Darwin. New York, NY: WW Norton & Co; 1969.
5. Orrego F, Quintana C. Darwin's illness. Notes Rec R Soc Lond. 2007;61(1):23-29. FREE FULL TEXT
6. Moore J. Good breeding: Darwin doubted his own family's "fitness." Nat Hist. 2005;(Nov):45-46.
7. Darwin F, ed. The Life and Letters of Charles Darwin, Vol 3. Cambridge, UK: Cambridge University Press; 2009.
8. Smith J. Charles Darwin and Victorian Visual Culture. Cambridge, UK: Cambridge University Press; 2009.
9. Stebbins TE Jr. The Life and Work of Martin Johnson Heade. New Haven, CT: Yale University Press; 2000.
10. Gilman SL. Darwin sees the insane. J Hist Behav Sci. 1979;15:253-262. FULL TEXT | ISI | PUBMED
11. Todes DP. Darwin Without Malthus: The Struggle for Existence in Russian Evolutionary Thought. New York, NY: Oxford University Press; 1989.
12. Nowak MA. Five rules for the evolution of cooperation. Science. 2006;314:1560-1563. FREE FULL TEXT
13. Peirce CS. Chance, Love, and Logic. Lincoln: University of Nebraska Press; 1998.
14. Padel R. Darwin: A Life in Poems. New York, NY: Alfred A. Knopf; 2009.


SECTION EDITOR: JAMES C. HARRIS, MD


Arch Gen Psychiatry. 2009;66(11):1159-1161.

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