Portal de Periódicos da CAPES

History of Ecological Sciences, Part 42: Victorian Naturalists Abroad— Hooker, Huxley, Wallace

2012; Ecological Society of America; Volume: 93; Issue: 2 Linguagem: Inglês

10.1890/0012-9623-93.2.125

2327-6096

Frank N. Egerton,

History of Science and Natural History

The Bulletin of the Ecological Society of AmericaVolume 93, Issue 2 p. 125-159 CONTRIBUTIONSFree Access History of Ecological Sciences, Part 42: Victorian Naturalists Abroad— Hooker, Huxley, Wallace Frank N. Egerton, Frank N. Egerton Department of History, University of Wisconsin-Parkside, Kenosha, Wisconsin 53141. E-mail: frank.egerton@uwp.eduSearch for more papers by this author Frank N. Egerton, Frank N. Egerton Department of History, University of Wisconsin-Parkside, Kenosha, Wisconsin 53141. E-mail: frank.egerton@uwp.eduSearch for more papers by this author First published: 01 April 2012 https://doi.org/10.1890/0012-9623-93.2.125Citations: 5AboutSectionsPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Click here for all previous articles in the History of the Ecological Sciences series by F. N. Egerton Hooker, Huxley, and Wallace were leading English naturalists during the Darwinian Revolution (McCalman 2009:83–362). They made substantial contributions to ecological thought in many of their publications. We have already reviewed Wallace's Amazonian experiences and observations (Egerton 2011). His Malay experiences, observations, conclusions are discussed here. However, Hooker is discussed first and then Huxley. Joseph Dalton Hooker (1817–1911) was the son of botanist William Jackson Hooker (1785–1865), who became Director of the Royal Botanic Gardens, Kew. The son would succeed his father in that position, and both were knighted for their services. In 1839, Joseph received an M.D. degree from Glasgow University, where William taught until 1841. Joseph's bibliography is included in his first biography (Huxley 1918, II:486–506). A later Kew botanist, W. B. Turrill, compiled an anthology of Joseph Hooker's phytogeographical writings (1953), which is a valuable resource of ecological interest. Some of Hooker's writings are also reprinted at the Joseph Dalton Hooker web site. Inspired by the travelogues of Humboldt and Darwin, Joseph had the connections to obtain a position of assistant surgeon and naturalist on a British naval expedition to the Antarctic in 1839 in Erebus, one of two ships under the command of an experienced polar explorer, Captain James Clark Ross (1800– 1862), who would seek to map Tasmania, New Zealand, other southern islands, and part of Antarctica in September 1839–September 1843 (Bravo 2004). Hooker was as well trained for this adventure as Darwin had been for his (Huxley 1918, I:1–36, Reed 1942:129–131, Turrill 1963:1–12, Allan 1967:84– 94, Desmond 1972, 1999:11–15, Bellon 2000, Endersby 2004a, b, 2008) (on Darwin's training, Egerton 2010:398–399). Hooker was appointed Assistant Surgeon and Botanist; and the Surgeon–Zoologist was Robert McCormick (1800–1890), who had been on a previous expedition. In 1839, before leaving, Hooker had walked through Trafalgar Square with a naval officer who had sailed with Darwin on the Beagle; they encountered Darwin, and the officer introduced them to each other (Huxley 1918, I:487). Just as Darwin took a copy of Humboldt's travels on his voyage, so Hooker took Darwin's Journal of Researches with him on the expedition (a gift from Charles Lyell), and read it often (Raby 1996:28). Hooker's task was simpler than Darwin's, because Darwin had collected animals, plants, and fossils, whereas Hooker mainly collected plants (his illustrations of a squid, Loligo gahi, and a fish, Pagothenia phocae, are reproduced by Desmond [1999:168–169]). He did trail plankton nets from his ship as it sailed along, and Christian Gottfried Ehrenberg (1795–1876), Humboldt's companion in Siberia, described his diatoms, but he never found anyone to study his other plankton and larger animals (Huxley 1918, I:56–60). However, Hooker was as diligent as Darwin, and after returning home, he published an account of all his plants, with collaborators only on brief articles on mosses and algae (Huxley 1918, II:487–490, Turrill 1963:24, Stafleu and Cowan 1976–1988, II:269–272, Desmond 1999:276, Short 2004:297–304). His Botany of the Antarctic Voyage was three works in six volumes: (1) Flora Antarctica (two parts, 1844–1847), (2) Flora Nouvae-Zelandiae (two parts, 1852–1855), (3) Flora Tasmaniae (two parts, 1855–1860). The titles of these works indicate the main parts of the voyage, and his main plant collections. Although Hooker did not publish a travelogue of his four-year expedition, his father published a long article based on his letters and notes (Hooker 1843), and Captain Ross did publish a narrative of the voyage (two volumes, 1847), which included six quotations from Hooker, each quotation 4–6 pages long. Hooker's first biographer, Leonard Huxley (1918, I:37–167), reconstructed a narration of the voyage from letters and other documents. H.M.S. Erebus and Terror embarked on their four-year voyage on 30 September 1839, and reached Cape Verde islands on 13 November. Hooker was a talented artist, whose sketches of landscapes and plants were later transformed into publishable plates by Walter Hood Fitch (1817–1892), a botanical artist at Kew (Desmond 1977:224, 1999:90–91). The ships entered Porto Praya, San Jago Island, where Hooker collected 110 plant species and sketched the arid landscape. He was unable to travel 12 miles inland to the more fertile highlands (Hooker 1843:250), but he did measure a solitary baobab tree Adansonia digitata that was 38 feet in circumference and more than 60 feet high. These ships next stopped at St. Paul's Rocks in the middle Atlantic, where Hooker confirmed Darwin's observation that they contained no plants, though he found seaweed offshore. As they approached South Africa, he had a chance to examine a seaweed community (letter of 17 March 1841, Huxley 1918, I:72–73) Till within a few days no floating seaweeds have been seen, when they suddenly appeared whilst cruising off St. Helen's Bay about sixty miles north of the Cape, whilst we were beating to the Southward; they certainly (though only of one kind) gave a most exulted notion of a submarine forest, with its accompaniment of a parasitic vegetation; with fish for birds, corals for Lichens, and shells for insects. Whilst going six or seven knots through the water, we, stationed in the quarter boats, harpooned these weeds as we passed, and very good fun for botanizing it was; the largest brought on board had a short thick branching root from which sprang four great stems, the longest 24 feet…. It belongs to the genus Laminaria; the old stems are brown, with flat white corals on them, and some parasitic seaweeds; the matted roots contain numerous other seaweeds, shells, Crustacea, corals, Molluscae, Actineae and red-blooded worms. The leaves are infested with Patellas, Sertularias, and Flustrae. From one specimen I took four seaweeds and upwards of thirty animals, by carefully pulling the root to pieces. Nor were these large seaweeds; many were seen twice as large if not larger. What extraordinary power can have torn them up by the roots I cannot conceive, for, from their length, they must grow far below low water mark. On 3 May 1842, he wrote to his father from the Falklands that officers he had met from H.M.S. Arrow told him that "as the Macrocystis grows large, it finally weighs up the stone, which was its moorings, and then the whole plant goes off to sea, which fully explains the reason for our finding so much of it alive at sea." Since the Antarctic Voyage circumnavigated the Antarctic, Hooker could compare the floras of widely separated Kerguelen, Auckland, and Falkland islands and found they had some plants in common (Huxley 1918, I:75). The expedition spent over two months (12 May–20 July 1840), at the Kerguelens (Îsles de Désolation), about latitude 49°S, making magnetic measurements, and Hooker increased its known species from 18 to 150 (Turrill 1963:27–28). His discoveries there included an aquatic species that bloomed under two inches of ice (Huxley 1918, I:76). His analysis of the Kerguelen flora, in Flora Antarctica, indicated that its strongest similarities were to the Fuegian flora of Cape Horn (quoted in Turrill 1953:190). The previously known Kerguelen cabbage (Pringlea antiscorbutica), as its scientific name indicates, was publicized by Captain James Cook as an antidote to scurvy. Hooker first adequately described and illustrated it, grew 50 plants from its seeds, and planted them at various places for later explorers. His expedition also left sheep at Kerguelen for the future benefit of whalers (with no thought of their impact on the island's environment). In November 1840, the expedition reached Campbell Island, south of New Zealand. Hooker's botanical observations there were quoted in Ross' A Voyage of Discovery and Research in the Southern and Antarctic Regions (1847, I:158–163 and reprinted by W. B. Turrill; this is the introductory paragraph [Turrill 1953:134–135]) Although Campbell's Island is situated 120 miles to the southward of Lord Auckland's group, and is of much smaller extent, it probably contains fully as many native plants. This arises from its more varied outline, and from its steep precipices and contracted ravines, affording situations more congenial to the growth of grasses, mosses, and lichens. Its iron-bound coast and rocky mountains, whose summits appear to the eye bare of vegetation, give it the aspect of a very desolate and unproductive rock, and it is not until the quiet harbours are opened, that any green hue save a few grassy spots is seen. In these narrow bays the scene suddenly changes; a belt of brushwood, composed of some of the trees mentioned as inhabitants of the last-visited island, but in a very stunted state, form a verdant line close to the beach. This is succeeded by bright green slopes, so studded with the Chrysobactron as to give them a yellow tinge, visible a full mile from the shore. Most of the beautiful plants of Lord Auckland's group, including the elegant caulescent ferns, are equally abundant here, and from many of them growing in this higher latitude at a proportionally lower elevation, their beauty strikes every one on first landing. In two days he collected over 200 species and thought he could have found more if he had had more time. On the other side of the world, on 5 January 1843, the expedition reached Cockburn Island, south of the Falkland Islands at latitude 64°12′ S (not named on the map, Fig. 1, but the expedition's route from the Falklands is indicated). The Arctic Circle is at latitude 66°30′ S, so not that far south, but some 15° in latitude south of the Kerguelens. He found on Cockburn only 19 species, all mosses, algae, and lichens. He explained their habitats and ranges (Ross 1847, II:335, quoted in Turrill 1953:137) Figure 1Open in figure viewerPowerPoint Map of the Antarctic voyage of Erebus, 1839–1843, from Cape Town, South Africa, and back (Turrill 1963:19). A larger-scale map is in Desmond 1999: inside front cover. Figure 2Open in figure viewerPowerPoint Porto Praya, San Jago Island, Cape Verde, showing Erebus and Terror in the harbor. By Walter Fitch, based on Hooker's sketch. Desmond 1999: title page and 27. Twelve are terrestrial; three inhabit either fresh water or very moist ground; and four are confined to the surrounding Ocean. Of these nineteen plants, seven are restricted to the island in question, having been hitherto found nowhere else (besides an eighth, which is a variety of a well known species); the others grow in various parts of the globe, some being widely diffused. Details on individual species follow, and then this overview (Ross 1847, II:341, quoted in Turrill 1953:138–139) Vegetation could not be traced above the conspicuous ledge of rocks, with which the whole island is girt, at fourteen hundred feet elevation. The lichens ascend the highest. The singular nature of this flora must be viewed in connection with the soil and climate; than which perhaps none can be more unfriendly to vegetable life. The form of the island admits of no shelter: its rocks are volcanic, and very hard, sometimes compact, but more frequently vesicular. A steep stony bank descends from the above-mentioned ledge to the beach; and to it the plants are almost limited. The slope itself is covered with loose fragments of rock, the débris of the cliff above, further broken up by frost, and ice-bound to a depth which there was no opportunity of ascertaining; for on the day the island was visited, the superficial masses alone were slightly loosened by the sun's rays. Thus the plants are confined to an almost incessantly frozen locality, and a particularly barren soil, liable to shift at every partial thaw. During nearly the entire year, even during the summer weeks which the Expedition spent in sight of Cockburn Island, it was constantly covered with snow….The vegetation of so low a degree of latitude might be supposed to remain torpid, except for a few days in the year; when if the warmth were genial, and a short period of growing weather took place, the plants would receive an extraordinary stimulus. But far from such being the case, the effect of the sun's rays, when they momentarily appear, is only prejudicial to vegetation. The black and porous stones quickly part with their moisture; and the Lecanora and Ulva consequently become so crisp and parched, that they crumble into fragments when an attempt is made to remove them. Turrill (1953:140–196) provides many quotable extracts from Flora Antarctica, but those above show well enough Hooker's sharp eye and ecological reasoning. What he learned during the four-year expedition became a valuable part of his cumulative knowledge of plants worldwide and their distributions. "He became the outstanding English geo-botanist of the century, and his distinction was founded upon an unrivalled basis of experience on the ground" (Raby 1996:127). A modern biogeographer, Philip Darlington, summarized Hooker's conclusions (1965:4) He thought that "land communications" between the areas in question were required for the higher orders of plants, but that spore-bearing forms might have been carried long distances by the "violent and prevailing westerly winds." And he thought that cold-adapted subantarctic plants isolated on mountains on New Zealand must have dispersed while the climate was colder than now and must have been stranded on mountain tops by a change (warming) of climate. Darlington commented: "The land communications are very doubtful; the change of climate is certainly correct in general." Darwin had presented his plants from his own voyage to Henslow, but as we saw (Egerton 2010:417), Henslow had only described two Opuntia from Galápagos and the plants from South Keeling Island. He suggested turning over the others to Hooker (who married Henslow's eldest daughter). Hooker was very busy describing his own specimens, but he found the time to describe Darwin's Galapagos species (Egerton 2010:417). They became best friends. For four years Hooker worked on publishing his Antarctic Flora, and then, before finishing, obtained commissions to collect fossils for the Geological Survey and plants for the Royal Botanic Gardens. (Fossils he had collected on the Antarctic voyage got mislaid and were relocated in 2011.) He left on 11 November 1847 for a three-year expedition to India. He reached Calcutta on 12 January 1848 (Huxley 1918, I:223, 233, Desmond 1999:96–98). This was a land expedition (Coats 1969:157–168, Desmond 1999:99–177, Short 2004:57–69), prompted to some extent by discussions with Darwin over the relationship between elevation and vegetation (Reidy 2010:28–29). Although Hooker published early impressions (1848), it was his superb Himalayan Journals 1854 that provided valuable information, more readily available than for his Antarctic expedition. One historian thinks this book is "one of the few and certainly one of the most accomplished examples for India of a scientific travel narrative comparable to those of Humboldt, Darwin, and Wallace" (Arnold 2005a:185, b). Hooker remained in India long enough "to profit handsomely from accumulated colonial (and even, to a degree, indigenous) knowledge." Observations of the correlation between climate and vegetation, which he began during the Antarctic voyage continued in India (Hooker 1891:30, Turrill 1953:30) Though the botany of Paras-nath proved interesting, its elevation was not accompanied by such a change from the flora of its base as I had expected. This is no doubt due to its dry climate and sterile soil; characters which it shares with the extensive elevated area of which it forms a part, and upon which I could not detect above 300 species of plants during my journey. Yet, that the atmosphere at the summit is more damp as well as cooler than at the base, is proved as well by the observations as by the vegetation; and in some respects, as the increased proportion of ferns, additional epiphytal orchidous plants, Begonias, and other species showed, its top supported a more tropical flora than its base. He occasionally suffered from Humboldtian impulses, as in the Soane Valley (Hooker 1891:26, Turrill 1953:31) Finding the fresh milky juice of Calotropis to be only 72°, I was curious to ascertain at what depth this temperature was to be obtained in the sand of the river-bed, where the plant grew.Surface . . . . . 1041/2°1 inch. . . . . 1022 inches. . . 9421/2 inches . . 9031/2 inches. . 85 Compact.8 inches . . . . 73 Wet.15 inches . . . 72 Ditto.The power this plant exercises of maintaining a low temperature of 72°, though the main portion which is subterraneous is surrounded by a soiled heat to between 90° and 104°, is very remarkable, and no doubt proximately due to the rapidity of evaporation from the foliage, and consequent activity in the circulation. Its exposed leaves maintained a temperature of 80°, nearly 25° cooler than the similarly exposed sand and alluvium. On the same night the leaves were cooled down to 54°, when the sand had cooled to 51°. Before daylight the following morning the sand had cooled to 43°, and the leaves of the Calotropis to 451/2°. I omitted to observe the temperature of the sap at the latter time; but the sand at the same depth (15 inches) as that at which its temperature and that of the plant agreed at mid-day was 68°. And assuming this to be the heat of the plant, we find that the leaves are heated by solar radiation during the day 8°, and cooled by nocturnal radiation 221/2°. In October 1848, Hooker began a three-month expedition into the Nepal Himalayas and on into Sikkim. He wanted to enter country unknown to Europeans, which required carrying food for most of the journey, and through country that pack animals might not be able to travel. His party of 56 people included 30 porters (Hooker 1969, I:168–169). As he ascended, he drew a correlation between the plant species found and their elevation (Hooker 1891:75, Turrill 1953:31–32). Species observed at 6000 feet included both vines and trees that embraced other trees and eventually killed the host, just as explorers had found in the Amazon basin. Continuing on to 12,000 feet elevation, he found (Hooker 1891:152–153, Turrill 1953:34) …sloping mountains clothed for 1,000 feet with dark-green rhododendron bushes; and detached masses of rock were scattered about, and to the right and left snowy peaks towered over the surrounding mountains, while amongst the latter narrow gulleys led up to blue patches of glacial ice, with trickling streams and shoots of stones. Dwarf rhododendrons with strongly-scented leaves (R. anthopogon and setosum), and abundance of a little Andromeda, exactly like ling, with woody stems and tufted branches, gave a heathery appearance to the hill-sides. The prevalence of lichens, common to this country and to Scotland (especially L. geographicus), which coloured the rocks, added an additional feature to the resemblance to Scotch Highland scenery. Hooker began publishing a book in London on the rhododendrons of the Sikkim Himalayas in 1849, while he was still in India, edited by his father, with lithographs by Walter Fitch, based on Hooker's sketches (Allan 1967:182). He also introduced many rhododendron species into British gardens. "On the climate and vegetation of the temperate and cold regions of East Nepal and the Sikkim Himalaya Mountains" (1852) was one of Hooker's most ecologically interesting writings. Although its purpose was to facilitate cultivating rhodendrons in Britain, and it appeared in a horticultural journal, it provided information on topography, climate, and which of 28 species are found at three elevations: 6000–10,000 feet, 10,000–14,000 feet, and 14,000–18,000 feet (1852:91–103). Three species were epiphytes, because in a moist climate, they found it easier to sprout on mossy limbs than in impenetrable undergrowth (Hooker 1852:72). On 9 September 1849, Hooker reached Donkia Pass, 18,466 feet elevation, eclipsing his hero Humboldt's ascent of Chimborazo (18,096 feet). On 13 September he scaled the flanks of Donkia to 19,300 feet. However, he was not climbing mountains just because they were there (Huxley 1918, I:304–305). I have a set of most curious new plants from between 17 and 19,000 feet—Woolly Lactuceae and Senecioneae like Culcitium, Gentians, Chrysanthemums, Saxifrages of course, Cyananthi, and some very odd things. They are extremely scarce and require close hunting. Sometimes I get but one or two specimens of a kind, and poking with a headache is very disagreeable.…I was greatly pleased with finding my most Antarctic plant, Lecanora miniata, at the top of the Pass, and to-day I saw stony hills at 19,000 feet stained wholly orangered with it, exactly as the rocks of Cockburn Island were in 64° South; is not this most curious and interesting? To find the identical plant forming the only vegetation at the two extreme limits of vegetable life is always interesting; but to find it absolutely in both instances painting a landscape, so as to render its colour conspicuous in each case five miles off, is wonderful. Occasionally, Hooker's encyclopedic knowledge intrudes, as in this passage (1891:313–314, Turrill 1953:39). The vegetation in the neighbourhood of Lamteng is European and North American; that is to say, it unites the boreal and temperate floras of the east and west hemispheres; presenting also a few features peculiar to Asia. This is a subject of very great importance in physical geography; as a country combining the botanical characters of several others, affords materials for tracing the direction in which genera and species have migrated, the causes that favour their migrations, and the laws that determine the types or forms of one region, which represent those of another. A glance at the map will show that Sikkim is, geographically, peculiarly well situated for investigations of this kind, being centrally placed, whether as regards south-eastern Asia or the Himalayan chain. Again, the Lachen valley at this spot is nearly equi-distant from the tropical forests of the Terai and the sterile mountains of Tibet, for which reason representatives both of the dry central Asiatic and Siberian, and the humid Malayan floras meet there.The mean temperature of Lamteng (about 50°) is that of the isothermal which passes through Britain in lat. 52°, and east Europe in lat. 48°, cutting the parallel of 45° in Siberia (due north of Lamteng itself), descending to lat. 42° on the east coast of Asia, ascending to lat. 48° on the west of America, and descending to that of New York in the United States. This mean temperature is considerably increased by descending to the bed of the Lachen at 8,000 feet, and diminished by ascending Tukcham to 14,000 feet, which gives a range of 6,000 feet of elevation, and 20° of mean temperature….the climate and vegetation becomes Arctic at 12,000 feet… (Lamteng is not named on the map (Fig. 3) but it is in the Lachen Valley, which is named.) Hooker then illustrated the points just made with examples of genera. Figure 3Open in figure viewerPowerPoint Seaweed Macrocystis luxurians (top) and land plants. Hooker 1844–1847, II: Plate 171. Figure 4Open in figure viewerPowerPoint Kerguelen cabbage Pringlea antiscorbutica. Hooker 1844–1847, II: Plates 90–91. Figure 5Open in figure viewerPowerPoint Joseph Dalton Hooker, age 32, by William Tayler (1808–1892) in 1849. Huxley 1918, I: facing page 340. Tayler was Postmaster General of Bengal. Figure 6Open in figure viewerPowerPoint Map of northeastern India and the Kangchenjunga area (inset), where Hooker mainly collected. Turrill 1963:57. Figure 7Open in figure viewerPowerPoint Tambur River at the lower limit of firs. By Walter Fitch based on Hooker's sketch, November 1848. Hooker 1969, I:198. Figure 8Open in figure viewerPowerPoint Rhododendron thomsonii, named by Hooker for his friend Thomas Thomson. By Walter Fitch, based on Hooker's sketch. Hooker 1849–1851. Figure 9Open in figure viewerPowerPoint "The botanist in Sikkim," by William Tayler, 1849, perhaps modified by Fitch. Desmond 1999:138. Figure 10Open in figure viewerPowerPoint Daguerreotype of Thomas Henry Huxley, 1857. Huxley 1900, I: facing 149. Figure 11Open in figure viewerPowerPoint Huxley's drawing of himself (center) on a brief expedition on the York Peninsula, Australia. Desmond 1997. On 1 May 1850, Hooker was joined by his friend from university, Thomas Thomson (1817–1878), a surgeon in the East India Company (Coats 1969:164, Desmond 1977:609–610, Endersby 2008:50–51). They explored the Khasia Mountains of Assam (Fig. 3). Hooker concluded that the Khasia flora was the richest in India, with 250 orchid species, growing on trees, rocks, in woods, and on grassy slopes. There were 150 kinds of ferns, and they collected a total of over 2500 species. But Khasia also had heavy rainfall—500 inches during their seven-month stay (Turrill 1963:71–72). Hooker left Calcutta on 28 January 1851 and reached England on 25 March. He was not yet ready to focus entirely on India, because he had only published Flora Antarctica before going to India; he still had to publish Flora Novae-Zelandiae (1852–1855) and Flora Tasmaniae (1855–1859). He published the "Introductory Essay" on 6 December 1853 (pages i–xxxix; excerpts in Turrill 1953:144–156, Lomolino, Sax and Brown 2004:109–117), in which he discussed the nature of species and their distributions. He had read Darwin's 1844 essay on the origin of species, but had not been persuaded. He wanted to determine what could be clearly known. Besides his Himalayan Journals, he coauthored Flora Indica 1855 with Thomas Thomson (1817–1878), a planned multivolume work of which only the first volume appeared (Endersby 2004c, Woodward and Grout 2004). Hooker wrote a 280-page "Introductory Essay" to it, excerpts being reprinted by Turrill (1953:48–57). In addition to being a masterful summary of Indian botany, it is a further example of Hooker's thinking on the nature of species, with Darwin in the back of his mind. Hooker also wrote the text for Illustrations of Himalayan Plants 1855. In 1872, he began, with various collaborators, to publish The Flora of British India (seven volumes, 1872–1897). In 1904, he had a final opportunity to summarize his accumulated knowledge of Indian plants; he divided them into nine provinces and discussed each province separately, with a map (excerpted in Turrill 1953:xii [map] + 57–68). In 1856, Darwin asked him to critique part of his own big book on species, attempting to explain the distribution of Arctic species on mountain tops (Browne 1983:131–134). Darwin hypothesized icebergs as means to transport seeds of plants from Arctic regions floating south. Hooker had first-hand experience with icebergs and had never seen one carry seeds. Furthermore, if icebergs were the means of dispersal, then the floras of mountaintops should show a random distribution similar to island floras, which was not the case. Hooker enjoyed expeditions, but for Huxley, as for Darwin, it was a once-in-a-lifetime adventure. Thomas Henry Huxley (1825–1895) was from Ealing, a village near London (Huxley 1900, Williams 1972, Di Gregorio 1984, Desmond 1997, White 2000, 2003, 2004). He was soon apprenticed to medical practitioners, and ambition motivated him to read extensively and join the navy as assistant surgeon. Captain Owen Stanley (1811–1850) of H.M.S. Rattlesnake (West 1967), a surveying ship similar to those on which Darwin and Hooker had sailed, obtained Huxley's services after consulting Sir John Richardson (Desmond 1997:40; on Richardson, see Egerton 2011). The Rattlesnake surveyed the waters and coast of New Guinea and eastern Australia, 1846–1850. Stanley was son of Bishop Edward Stanley (1779–1849), president of the Linnean Society of London (Prothero and Matthew 2004), and Huxley would send scientific papers to the bishop during the voyage. Before departing, Edward Forbes advised Huxley on the collecting and study of marine life. Huxley's Rattlesnake diary (Huxley 1935) tells what he did and with whom he interacted (he met his future wife in Sydney), but did not contain his zoological observations, as did Darwin's Beagle Diary (then unpublished). He kept a parallel