Charles Robert Darwin ( 1809 - 1882 )

Not until the later half of the eighteenth century and the structural peculiarities of orchid flowers attract the serious attention of naturalists. Lee (1765) became interested in these curious structures , followed by Kurt Sprengel (1793), who observed the role of insects in the pollination of orchids . Weachter (1801) observed that native terrestrial orchids failed to set seed unless visited by insects , and Robert Brown's paper on the reproductive structures of orchid , read before the Linean Society in 1831,established the presence of the nucleus ,the " heart " of the living cell. A few weeks later a young naturalist set sail on H.M.S. Beagle,an epoch-making voyage that resulted in biological discoveries that were to shake the foundations of scientific and religious opinion and change the philosophical attitudes of mankind . This young man was Charles Darwin , the learned and versatile " evolutionist" whose observations of the orchid's reproductive parts led to the confirmation of his theory of evolution through natural selection and competition . Much of what orchidology now knows of the relationships of orchids and insects is based on Darwin's discoveries over 100 years ago.

Charles Robert Darwin was born at The Mount ,Shrewbury ,England , on 12 February 1809. He was the son of Dr. Charles Waring Darwin and the grandson of Dr. Erasmus Darwin, a naturalist whose speculations were to have a profound influence on the younger family scion.

Young Charles was educated at the grammer school at Shrewsbury , thence he went to Edinburgh (1825) and afterward to Cambridge .He din not excel in school., however. He was, in fact, considered rather below the common standard in intellect.He became a pupil of Professors Henslow and Sedgewicke at Cambridge,and under their guidance his consuming interest in botany began to bear fruit. He received his degree at Cambridge in 1831 and shortly thereafter , at the age of twentytwo , joined a hydrographical survey as an unpaid naturalist on H. M.S Beagle. For five years he served aboard the Beagle , studying the flora, fauna , and geology of numerous temperate, subtropical , and tropical districts sorrounding South America. This historic round-the -world voyage which Darwin later referred to as " by far the most important event in my life," laid the foundations for the remainder of his life's work, placing him among the foremost of rising natuaralists . The results of his services were given in his Journal of Researches into the geology and natural history of the countries visite.

Darwin was not a robust man even in his young manhood but he was a zealous naturalist who refused to be shackled by illness; on his return to England he began to write and experiment extensively ,despite poor health, exploring all the sciences of earth, life, and man. Thus he rose to renown.Few were privileged to know him on a close personal level, however, for owing to his always feeble health and retiring nature, he seldom entered into social functions or close personal relationships . Instead he labored diligently and introspectively in the pursuit of scientific study. By his work at the Geological Society ,and by his numerous papers on coral reefs , the natural history of the cirrhipeds,and many other biological researches he gained fame as an authority.

In 1838 he accepted the appointment as secretary of the Geological Society and was elected to the Royal Society the following year. Meanwhile ,he had married his cousin , Emma wedgwood , and settled in Down,kent , shortly thereafter . Years of study and writing followed .

Darwin held that no higher plant could fertilize itself for a perpetuity of generations without the intercession of being cross-fertilized with some other individual . This theory he published in 1859 in his work entitled On the Origin of Species by Means of Natural Selection . This work brought him controversial fame as it called down upon him a shower of blame and abuse for propounding such a theory without providing absolute proof.

Native terrestrial orchids grew in abundance near Darwin's home and , because they were the " most singular and modified forms in the vegetable kingdom, " he began an extensive study of their reproduction in order to prove his theory of cross-fertilization aganist that of self-fertilization . With his son and his friends often assisting him in his observations , he spent unnumbered hours in the garden and fields making notes on the number of flowers that set seed; setting up controls by the use of nets and bell jars; catching bees and moths and examining the showy markings and structures of species which were consistent in attracting natural pollinators . Early in his reserches he noted the pollination of Orchis pyramidalis by a particular moth, and studied such unusual adaptations as the " flinging " of pollen onto the pollinator in the genus Catasetum and the pollination of Ophrys by pseudo-copulation.

The studies were of such interest to Darwin that he shortly initiated a copious correspondence with Sir Joseph Hooker (then assistant director at Kew), and a letter to Hooker in October 1861 he stated ," I never was more interested in any subject in my life than this of Orchids."

As his interest in the order became intensified , he began to study the pollinating devices of tropical orchids: the shooting mechanism of Catasetum species , the " bucket" lip of Coryanthes , and many others. Observing the remarkably lengthy nectary of Angraecum sesquipedale, he predicted that it must be necessary for some certain moth with a footlong tongue to be the pollinating agent for this remarkable species .

Finally gathering sufficient evidence to uphold his theories , in 1862 Darwin published his classic work, on the Fertilisation of Orchids by insects. This work put forth the results of his reservations and not only removed all doubt regarding the function of the pollinia , but drew the attention of naturalists to the complex symbiosis existing between flowering plants and food-seeking insects. The introduction of this book states his purpose :

.......... In my volume " On the Origin of Species " I gave only general reasons for the belief that it is an almost universal law of nature that the higher organic being require an occasional cross with another individual ; or ,which is the same thing ,that no hermaphrodite fertilises itself for a perpetuity of generations . Having been blamed for propounding this doctrine without giving ample facts , for which I had not sufficient space in that work , I wish here to show that I have not spoken without having gone into details.

I have been led to publish this little treatise separately, as it is too large to be incorporated with any other subject . As Orchids are universally acknoledge to rank amongst the most singular and most modified forms in the vegetable kingdom , I have thought that the facts to be given might lead some observers to look more curiously into the habits of our several native species....... This treatise affords me also an opportunity of attempting to show that the study of organic beings may be as interesting to an observer who is fully convinced that the structure of each is due to secondary laws ,as to one who views every trifflinf detail of structure as the result of the direct interposition of the Creator .

As the facts were brought together to bear on Darwin's theory ,the tide of feeling among naturalists turned in his favor . Known for his honesty ,his persistent study habits, and his unprejudiced devotion to truth , he gained immediate support from such men as Sir Joseph Hooker , Professor Huxley ,Mr. George Bentham , and others. Their " conversions" to a belief in evolution were remarkably rapid, and even the educated minority of the population at large soon grasped evolutionary concepts.

For the remainder of his life Darwin studied ,reserched , and made many important contributions to geology, zoological geography , taxonomy ,ecology , and animal breeding . He died on 19 April 1882, at the age of seventy-three.

Other of his important works in the various fields of science include The Structure and Distribution of Coral Reefs ,The Descent of Man , Geological Observations in South America, Insectivorous Plants , Cross and Self-Fertilisation in the Vegetable Kingdom, Formation of Vegetable Mold ,Emotions im Man and Animals , Principles of Variation Under Domestication, adn The Power of Movement in Plants .

Darwin's orchid studies become the basis of a number of later works by succeeding naturalists and botanists , but while his contributions to orchidology were therefore unprecedented in pollination studies , their importance is equally shared in science as a breakthrough which resulted in theories that changed the whole foundation of scientific knowledge .

References

American Orchid Society Bulletin . 1940 .Vol. 9, no.6,p. 151.

Ames . Oakes . 1937. Pollination of orchids through pseudocopulation. Botanical Museum Leaflets 5 , no. 1 .Cambridge , Massachusetts : Harvard University Press.

Ames , Oakes . 1941.Pollination in Coryanthes . Amer . Orch. Soc. Bull. 10, no.6.

Ames ,Oakes . 1944. The pollinia of orchids . Amer . Orch.Soc. Bull. 13 , no.6.

Darwin , Charles . 1903.Various Contrivances by which Orchids are Fertilised by Insects . 2 ed ., rev. New York.

Gardeners' Chronicle . 1882. Death of Charles Darwin .Vol. 17, no . 434.

Gibson William Hamilton , and Jelliffe , Helena Leeming . 1905 . Our Native Orchids. NewYork : Doubleday , Page & Co.

Orchidata . 1966. 5, no.6.

Worldscope Encyclopedia . 1953.Vol.4. The Universal Guild , Inc.