Bates, Henry Walter

views updated May 23 2018

Bates, Henry Walter

(b. Leicester, England, 8 February 1825; d. London, England, 16 February 1892)

natural history.

The eldest son of Henry Bates, a hosiery manufacturer at Leicester, Henry received his elementary education in the schools there before attending Mr. H. Screaton’s boarding school at Billesden, a village about nine miles from Leicester. Although Bates was an excellent student, his formal education was terminated in midsummer 1838, and he was apprenticed to a local hosiery manufacturer, for whom he labored thirteen hours a day. His capacity for work was prodigious, however, and he also took night classes at the local Mechanic’s Institute, where he excelled in Greek, Latin, French, drawing, and composition. (Later, while in South America, he taught himself German and Portuguese.) Throughout his life Bates read very widely and was particularly fond of reading Homer in the original and Gibbon’s monumental Decline and Fall of the Roman Empire. Music also engaged some of his time: he sang in the local glee club, played the guitar, and maintained a strong interest in classical music throughout his life.

In addition to these numerous activities, Bates was an avid entomologist and, with his brother Frederick, scoured the woods of nearby Charnwood Forest for specimens during his holidays. His earliest scientific work, a short paper on beetles (1843), was published in the first issue of The Zoologist when he was eighteen years old.

His supervisor died several years before Bates’s apprenticeship was completed, and Bates assumed management of the firm for the son before becoming a clerk in nearby Burton-on-Trent. He strongly disliked his work, however; entomology was a much more congenial occupation, and he habitually spent much of his time writing detailed accounts of his expeditions and captured treasures. In 1844 (or 1845) Bates befriended Alfred Russel Wallace, a mutually beneficial act that profoundly influenced both their lives. Wallace was then a master at the Collegiate School at Leicester and in his spare time enthusiastically pursued his own amateurish interests in botany. Bates introduced him to entomology, and the two friends continued to correspond and exchange specimens after Wallace moved from Leicester early in 1845.

While exchanging specimens in 1847, Wallace audaciously suggested to Bates that they should travel to the tropical jungles to collect specimens, ship them home for sale, and gather facts “towards solving the problem of the origin of species”—a frequent topic of their conversations and correspondence. Wallace’s attention had been directed to South America by the vivid prose of William H. Edward’ Voyage up the River Amazon, Including a Residence at Pará (1847); conversations with the author increased their interest, as did Edward Doubleday of the British Museum, who showed them some exquisite new species of butterflies collected near Pará (Belém), Brazil, and offered other encouragement. Arrangements were soon made, and after a swift voyage of thirty-one days, the two amateur naturalists disembarked on 28 May 1848 at Pará, near the mouth of the Amazon River. Althoug Wallace returned to England in July 1852, Bates remained for a total of eleven years, exploring and collecting within four degrees of the equator. Frequently discouraged by his chronically destitute condition and his isolation, he was nevertheless held there by an intense passion for collecting: the “exquisite pleasure of finding another new species of these creatures supports one against everything.” Bates conservatively estimated that he had collected 14,712 animal species (primarily insects) while in South America; more than 8,000 of these were new to science. Despite the richness of his collections, he received a profit of only about £800 for his efforts—or about £73 a year.

From Pará Bates traveled almost 2,000 miles deep into the wilderness. He resided in Pará for a total of nearly eighteen months, returning there periodically for a few months after each of his shorter excursions to the interior. On 26 August 1848 Bates and Wallace embarked on a journey up the Tocantins River; they arrived in October 1849 at what was to be Bates’s headquarters for three years—Santarém, a small town of 2,500 inhabitants some 475 miles from the sea at the mouth of the Tapajós River. By mutual agreement Bates and Wallace parted company on 26 March 1850 at Manaus, the latter departing for the Rio Negro and the Uaupés. Manaus, at the confluence of the Rio Negro and the upper Amazon (Solimões), was a classic hunting ground for naturalists, having been a favorite spot for the celebrated travelers J. B. von Spix and K. F. P. von Martius, who had stayed there in 1820. On 6 November 1851 Bates set out to explore the Tapajós and Solimões river basins, spending a total of seven and one-half years there. His headquarters during his four and one-half years in the Solimões area was at Ega (Tefé), at the foot of the Andes. In September 1857 he plunged deep into the wilderness to São Paulo, some 1,800 miles from Pará. Finally, on 11 February 1859, Bates left Ega for Pará and England, his chronically poor health at its nadir.

After arriving in England in the summer of 1859, Bates began work on his enormous collections under the influence of a specific biological concept. In the previous year the now famous papers of Charles Darwin had been presented to the Linnean Society of London, and in November 1859 Darwin published On the Origin of Species by Means of Natural Selection. Bates was an immediate convert, and had some substantial and impressive evidence of his own to contribute to Darwin’s arguments. (Bates’s Unitarian religious views did not hinder his acceptance of natural selection.) On 21 November 1861 Bates first expounded his ideas on mimicry in his famous paper “Contributions to an Insect Fauna of the Amazon Valley. Lepidoptera: Heliconidae,” which he read before the Linnean Society. With typical enthusiasm for works by his followers, Charles Darwin commented that Bates’s article was “one of the most remarkable and admirable papers I have ever read in my life.”

Responding to Darwin’s exhortations, Bates published early in 1863 a two-volume narrative of his travels in South America. The Naturalist on the River Amazon. This splendid work was one of the finest scientific travel books of the nineteenth century. The Naturalist went through many editions and was translated into several languages; nevertheless, popular and remunerative as it was, Bates remarked that he would rather spend another eleven years on the Amazon than write another book.

In 1862 Bates failed to secure a position in the zoology department at the British Museum—a post that went instead to A. W. E. O’Shaughnessy, a poet who, Bates said, was probably sponsored by Richard Owen. In 1864, however, Bates was appointed assistant secretary of the Royal Geographical Society of London, serving with distinction for twenty-eight years. Besides editing the Journal and Proceedings of the Society, as well as carrying on an immense correspondence with travelers and others throughout the world, Bates actually managed the Society and made arrangements for various meetings, including those held by the Geographical Section of the British Association.

During his tenure as assistant secretary, Bates’s published works were devoted almost exclusively to entomology, primarily systematics, and numerous editions of travel works, such as Peter E. Warburton’s Journey Across the Western Interior of Australia (1875), Thomas Belt’s The Naturalist in Nicaragua (1873), and six volumes of Cassell’s Illustrated Travels: A Record of Discovery, Geography and Adventure (1869–1875). His greatest contribution to systematic entomology appeared in various volumes of the Biologia Centrali-Americana, edited by F. D. Godman and O. Salvin (see his works on Coleoptera: Adephaga, {Pectinicornia [Passalidae and Lucanidae], Lamellicornia [Scarabaeidae], and Longicornia [Cerambycidae]), and his fame as a preeminent authority on Coleoptera was worldwide. He contributed more than one hundred scientific papers to scholarly journals, including the journals, corresponded with many entomologists, and served as consultant or assistant to various scientific journals, including the The Entomologist. (He also published anonymously purely literary works, and was at one time on the staff of the Atheneum.)

Many honors were bestowed on Bates, although he was strongly disinclined to discuss them. In 1861 he was elected to the Entomological Society of London and served as president in 1868, 1869, and 1878. He was elected fellow of the Linnean Society in 1871, fellow of the Zoological Society in 1863, and fellow of the Royal Society in 1881. Although he was secretary of the Geographical Section of the British Association, he declined the office of president. For his work in Brazil, the emperor of that country bestowed on Bates the Order of the Rose, a distinction rarely conferred upon foreigners. In 1863 he married Sara Ann Mason of Leicester, who bore him one daughter and three sons, two of whom emigrated to New Zealand.

That Bates was an immediate, early convert to Darwinian natural selection is understandable, for he had long been an evolutionist, as had his friend and traveling companion Alfred Russel Wallace. However, Bates appears not be have been converted as quickly as Wallace was by the evolutionary explanations adduced by Robert Chambers in his heretical, but quite popular, Vestiges of the Natural History of Creation (1844 et seq.). In a letter to Wallace in 1845, Bates apparently had described Chambers’ ideas as hasty generalizations, a charge that Wallace felt compelled to answer at some length. By March 1850, when the two parted company to explore by themselves, they had often discussed the species question and had reached some tentative conclusions. Nevertheless, Bates expressed surprise at Wallace’s paper “On the Law Which Has Regulated the Introduction of New Species.”1 In this important work Wallace argued that every species has arisen “coincident in both space and time with a pre-existing closely allied species,” thus supporting species creation through natural laws—as opposed, by implication, to numerous special creations by God.

Bates wrote Wallace from the Amazon that he was at first startled to see that he was “already ripe for the enunciation of the theory,” commenting, however, “the theory I quite assent to, and, you know, was conceived by me also, but I profess that I could not have propounded it with so much force and completeness.” Wallace replied from the Malay Archipelago that his paper naturally would appear more clear to Bates than “to persons who have not thought much on the subject,” adding that the “paper is, of course, only the announcement of the theory, not its development....”2 Precisely what Bates meant by “the theory... was conceived by me alos” is a matter for conjecture, for Wallace apparently was the earlier convert to the evolutionary hypothesis and. i n fact. pleaded the evolutionist’s case quite forcefully to Bates. Furthermore, Wallace certainly had a far more pregnant imagination than Bates. and it was he who perceived in 1858 the solution to the problem. Bates’s original contribution to evolutionary biology appeared shortly after the Origin was published and fully corroborated Darwin’s theory of natural selection.

Before 1861, naturalists had observed that certain butterflies belonging to distinct groups inhabiting the same geographical area bear remarkable superficial resemblances in appearance, shape, and color. In 1836 J. A. Boisduval had described the African swallowtailed butterfly, which was copied by quite distinct butterflies. The distinguished English entomologists William Kirby and William Spence had observed in 1817 that the flies of the genus Volucella enter bees’ nests to deposit their eggs so that their larvae may feed on the bee larvae and that the flies curiously resemble the bees on which they are parasitic. They concluded that the resemblance exists to protect the flies from possible attacks by the bees. In an article published in 1861, the German entomologist A. Rössler enumerated many examples of mimicry, which he explained as a device to protect insects from their enemies. In general, however, belief in the handiwork of God sufficed to explain the phenomenon, although some thought that there might be an innate tendency in insects to vary in a particular direction.

Bates was the first naturalist to venture a comprehensive scientific explanation for the phenomenon that he labeled “mimicry” (Batesian mimicry). Batesian mimicry should here be differentiated from Müllerian mimicry, According to Cott:

In Batesian mimicry a relatively scarce, palatable, and unprotected species resembles an abundant, relatively unpalatable or well-protected species and so becomes disguised, In Müllerian mimicry, on the other hand, a number of different species all possessing aposematic attributes and appearance resemble one another, and so become easily recognized [Adaptive Coloration in Animals, p. 398].

One therefore leads to deception of enemies and the other to the education of enemies by warning colors. Bates, and others, at first confused the two kinds of mimicry.

Bates’s discussion of mimicry was unobtrusively buried in his classic article on the heliconid butterflies of the Amazon, which were frequently mimicked by counterfeits so perfect that even Bates was unable to distinguish them in flight. The Leptalides (Dismorphia butterflies, although quite different structurally from the Heliconidae, are especially proficient mimics. Other examples abound. In various parts of the world beetles, spiders, flies, and grasshoppers mimic ants. While spiders may have a body configuration resembling that of ants, other mimics may use optical illusions to produce the appearance of a narrow antlike waist. Certain bees on the banks of the Amazon, as Bates observed, are also mimicked; indeed, many moths and longicorn beetles in the tropics mimic bees, wasps, and other hymenopterous insects. (Bates also adduced numerous examples of insects imitating objects.) In every case the mimic benefited to some extent from protection afforded by the original. The Heliconidae, which fly slowly and in plain sight of many potential enemies, are rendered foul-smelling and unpalatable by a glandular secretion. Birds and reptiles, to a lesser extent than insects, also mimic protected species. Bates observed an extra-ordinary example of a very large caterpillar that imitated a small, venomous snake. The first three segments behind the head could be dilated at will by the insect, and on each side of its head was a large pupillated spot resembling the eye of the poisonous snake. The general consternation produced among the natives when Bates displayed his specimen attests to the excellence of the imitation.

Granted that mimics are adaptations to their environment, the important question was why such remarkably close analogies exist, Bates ruled out direct action of physical conditions because in limited districts where these conditions were the same, the most widely contrasting varieties may be found co-existing. Likewise, sports (mutations) did not explain mimicry. To Bates in was quite clear that natural selection had produced these phenomena, “the selecting agents being insectivorous animals which gradually destroy those sports or varieties which are not sufficiently like [the protected species] to deceive them.” The closer the resemblance of the mimic to the original, the greater will be its protection. Imperfect copies will be eliminated slowly, unless they have some supplementary protection of their own. (In fact as V. Grant observed, “most animals in general have several alternative means of defense against their enemies” [The Origin of Adaptations, p. 112].) By observing the different forms of the mimic as it approximated (or diverged from) the original, species change itself could be carefully observed: “Thus, although we are unable to watch the process of formation of a new race as it occurs in time, we can see it, as it were, at one glance, by tracing the changes a species is simultaneously undergoing in different parts of the areas of distribution,”; 3 As Bates so aptly observed, it was “a most beautiful proof of natural selection.”

Darwin was thoroughly delighted with Bates’s paper, for it fully corroborated his theory and presented him with an excellent opportunity to rebut his critics in a short, unsigned review in the Natural History Review for 1863. He confronted the creationists with the embarrassing case of the mimicking forms of Leptalides (Dismorphia) butterflies, which could be shown through a graduated series to be varieties of one species; other mimickers clearly were distinct varieties, species, or genera. To be logically consistent—and they were not always—the creationists had to admit that some mimickers had been formed by commonly observed variations, while others were specially created. They would further be required to admit that some of these forms were created in imitation of forms known to arise through the ordinary processes of variation. The difficulties of such a position were insurmountable, and the arguments for Batesian mimicry were widely accepted. Moreover, A. R. Wallace soon extended these arguments in two excellent articles: “On the Phenomena of Variation and Geographical Distribution as Illustrated by the Papilionidae of the Malayan Region” (1865) and “Mimicry and Other Protective Resemblances Among Animals” (1867). Thereafter, the literature was rich with references to mimicry, reaching a high point toward the end of the century with extensive discussions by Wallace, Poulton, and Beddard.

On the other hand, Bates the author of the theory of mimicry, never published an extensive review of the subject, nor did he ever again write a philosophical or interpretative paper comparable to his article on mimicry. Unable to spin hypotheses as easily as did Darwin and Wallace, he devoted himself instead to numerous works on systematic entomology, such as his catalog of the Erycinidae (Riodinidae) butterflies, the foundation upon which subsequent authors worked. After selling his collections of Lepidoptera, Bates concentrated on Coleoptera, especially Adephaga, Lamellicornia and Longicornia.

That Bates failed to produce further works comparable to those on mimicry and his Travels has generally been attributed to the press of his many duties at the Royol Geographical Society. However, the character of his later work on entomological systematics may have been strongly influenced by other factors as well. In his presidential address to the Entomological Society in 1878, Bates discussed the “prevailing exclusively descriptive character of the entomological literature of the day,” which he thought resulted primarily from the difficulty of describing the prodigious influx of newly discovered species. Nature was proving to be far more prolific, and her products more varied, than had previously been thought. “Thus our best working Entomologists are led to abandon general views from lack of time to work them out, and the consciousness that general views on the relations of forms and faunas are liable to become soon obsolete by rapid growth of knowledge.” This, he felt, did not totally excuse the systematists’ excessive narrowness, for it led them to neglect natural affinities that greatly illuminated evolution, which in his opinion was the greatest problem in biology. While Bates himself searched for natural affinities and focused attention on the important problems of the geographical distribution of animals, his general observation about systematists may also have applied to him, as his friend D. Sharp observed. Nevertheless, his erudite papers formed the substance for those who were able to develop theories, while his paper on mimicry and his Travels stand as classics in their own right.


1.Annals and Magazine of Natural History, 2nd ser., 16 (1855), 184–196.

2. Bates to Wallace, 19 November 1856, and Wallace to Bates, 4 January1858, in Marchant, Alfred Russel Wallace: Letters and Reminiscences, pp. 52–55.

3. “Contributions to an Insect Fauna...,” in Transactions of the Linnean Society of London. 23 (1862), 512–513.


I. Original Works. Bates’s best-known works are “Contributions to an Insect Fauna of the Amazon Valley. Lepidoptera: Heliconidae,” in Transactions of the Linnean Society of London, 23 (1862), 495–566, in which he announced his theory of mimicry, and The Naturalist on the River Amazon, 2 vols. (London, 1863; repr. London, 1892). Many other contributions to the insect fauna of the Amazon appeared in entomological journals. His presidential addresses to the Entomological Society of London, in its Proceedings for 1868, 1869, and 1878, are valuable for understanding his general opinions on entomology and biology.

II. Secondary Literature. There are a number of informative obituaries on Bates; his neighbor and friend Edward Clodd had direct access to his papers (which have disappeared), which makes his account particularly valuable. See his memoir of Bates prefaced to the 1892 reprint of the first edition of Bates’s Travels. Other obituaries are R. McLachlan, “Obituary of Henry Walter Bates, F. R. S.,” in The Entomologist’s Monthly Magazine, 2nd ser., 3 (1892), 83–85; Proceedings of the Royal Geographical Society, 14 (1892), 245–257; D. Sharp, “Henry Walter Bates.” in The Entomologist, 25 (1892), 77–80; and Alfred Russel Wallace, “H. W. Bates, the Naturalist of the Amazons,” in Nature, 45 (1892), 398–399.

Except for letters to Darwin at Cambridge, scarcely any of Bates’s correspondence remains. Fortunately, however, some of his important letters have been published in the following works: Francis Darwin, ed., The Life and Letters of Charles Darwin, II (London, 1887), 378–381, 391–393; Francis Darwin and A. C. Seward, eds., More Letters of Charles Darwin, Vol. I (New York, 1903), passim; James Marchant, ed., Alfred Russel Wallace; Letters and Reminiscences (New York, 1916), pp. 52–59; and A. R. Wallace, My Life: A Record of Events and Opinions, I (London, 1905), 350–379.

On mimicry see Frank E. Beddard. Animal Coloration (London, 1892); Hugh B. Cott, Adaptive Coloration in Animals (London, 1940, 1957); Verne Grant, The Origin of Adaptations (New York-London, 1963); E. B. Poulton, The Colours of Animals, Their Meaning and Use (London, 1890); Charles L. Remington, “Mimicry, a Test of Evolutionary Theory,” in Yale Scientific Magazine, 22 , no. 1 (October 1957), 10–11, 13–14, 16–17, 19, 21, written with Jeanne E. Remington; and “Historical Backgrounds of Mimicry,” in Proceedings of the XVI International Congress of Zoology, IV (Washington, D. C., 1963), 145–149; and A. R. Wallace, Darwinism (London, 1889), pp. 232–267.

H. Lewsi McKinney

Bates, Henry Walter

views updated Jun 08 2018

Bates, Henry Walter

British Naturalist

Henry Walter Bates was born in Leicester, England. Bates was a naturalist who specialized in the study of insects.

Bates left school at the age of thirteen and worked in his father's stocking factory. He was an amateur botanist and entomologist. In 1844 Bates met Alfred Russel Wallace, who along with Charles Darwin originated the theory of evolution by natural selection. In 1847 Wallace suggested Bates accompany him on a trip to tropical jungles to study natural history. They would pay for their trip by collecting animal specimens and selling them in Europe. In 1848 Bates and Wallace arrived in Brazil at the mouth of the Amazon River. Wallace stayed for four years, and Bates for eleven years. During this time, Bates explored the entire valley of the Amazon and collected nearly 15,000 species, mostly insects. Of these species, 8,000 were previously unknown. Many of the specimens were sent back to museums and collectors in Europe to raise funds to pay for the trip.

After returning to England in 1859, Bates worked on his huge collections, classifying and describing the various species. He wrote a famous paper entitled "Contributions to an Insect Fauna of the Amazon Valley" and presented it to the scientific community in 1861. Bates also proposed a hypothesis about a certain type of mimicry which is now called Batesian mimicry . While in the Amazon valley, Bates observed that certain harmless butterflies looked very similar to other butterflies that were poisonous or distasteful to predators. Bates theorized that the harmless butterflies had evolved to look like the toxic butterflies. In this way, he believed that the harmless butterflies increased their chances of survival by taking advantage of the defenses of the toxic butterfly. A classic example of Batesian mimicry is the viceroy butterfly which looks very similar to the foul-tasting monarch butterfly. Bates was a strong supporter of evolution by natural selection, and his findings about mimicry supported this theory.

In 1864 Bates was appointed as the assistant secretary of the Royal Geographical Society in London. He held this position for twenty-eight years until his death. Bates is recognized among scientists for his contribution to the classification of scarabs, a type of beetle. He described over 700 new species of scarabs. Bates wrote The Naturalist on the River Amazons (1863) and many scientific papers on insects.

Denise Prendergast


Williams, Trevor I., ed. A Biographical Dictionary of Scientists, 3rd ed. New York: John Wiley & Sons, 1982.

Internet Resources

University of Nebraska State Museum. <>.

Bates, HenryWalter

views updated May 23 2018

Bates, HenryWalter (1825–92)An English naturalist who, in 1848, accompanied A. R.Wallace on an exploration of the Amazon, where he collected nearly 15 000 species of insects, 8000 of which were new to science. His studies of them led him to propose the way in which the mimicry named after him can arise among unrelated species. He received enthusiastic support from Darwin and Sir Joseph Hooker, and Darwin wrote an introduction to his only book, The Naturalist on the Amazons, published by John Murray in 1863.

Bates, Henry Walter

views updated May 11 2018

Bates, Henry Walter (1825–92) An English naturalist who, in 1848, accompanied A. R. Wallace on an exploration of the Amazon, where he collected nearly 15 000 species of insects, 8000 of which were new to science. His studies of them led him to propose the way in which the mimicry named after him can arise among unrelated species. He received enthusiastic support from Darwin and from Sir Joseph Hooker and Darwin wrote an introduction to his only book, The Naturalist on the River Amazon, published by John Murray in 1863.