South American Mainland Research Articles

Preliminary analysis of phylogenetic relationships among Galapagos Island lizards of the genus Tropidurus

Abstract Albumin evolution in six species of Galapagos iguanid lizards of the genus Tropidurus was measured using the quantitative immunological technique of micro-complement fixation. We propose a phylogeny for these species based upon their albumin differentiation. Our data suggest several colonizations from the South American mainland are needed to account for current species diversity on the Galapagos Islands. The standard calibration for the albumin molecular clock yields divergence estimates for Galapagos Tropidurus that are similar to those previously reported for the iguanas in the Galapagos and are not in conflict with recent understanding of the geological history of these islands.

Genetic Variation and Pathotype Response in Globodera Pallida (Nematoda: Heteroderidae) From the Falkland Islands

The pathotype composition and genetic variation in potato cyst nematode populations from the Falkland Islands were examined using differential potato clones and isozyme analysis. Only Globodera pallida was identified and pathotype data indicated a previously undetected pathotype response in a number of populations. Patterns of genetic heterogeneity highlighted distinct population groupings which may result from at least two introductions from the South American mainland.

Island Carib Origins: Evidence and Nonevidence

Origin stories collected among the indigenous peoples in the Windward Islands during the early colonial period have been interpreted as indicating a mainland Carib affiliation for the islanders. This interpretation gave rise to efforts in the present century to identify the archaeological correlate of the presumed late prehistoric or protohistoric migration of Cariban speakers into the Lesser Antilles. Recent debate centers around two models. One of these associates the supposed migration of mainland Caribs into the Lesser Antilles with the advent of the Suazey ceramic complex in the twelfth century; the other implies either a protohistoric migration or an episode of rapid acculturation of island populations to South American mainland Carib culture in the fifteenth or sixteenth centuries. A review of relevant archaeological, historical, and linguistic evidence provides little support for either of these models. Instead, the so-called “Island Caribs” were Arawakan speakers, probably longtime residents of the Windward Islands whose cultural and linguistic connections with the mainland Caribs probably were the products of contacts related to trade and alliance.

Earthquakes, Rivers and Ice: Scientific Research at the Laguna San Rafael, Southern Chile, 1986

The Laguna San Rafael, Aisen Province, southern Chile, is a tidal lagoon which receives the San Rafael glacier?the nearest tidewater glacier to the equator. The glacier is sustained by very high precipitation and pronounced topographic relief on the tectonically active western Andean margin. This area formed the focus for three research projects undertaken as part of an expedition mounted by Operation Raleigh in early 1986: investigating and dating subsidence events in association with past great subduction zone earthquakes; analysing the sedimentation of braided streams emerging from the North Patagonian ice field; and studying the tidal and meltwater dynamics of the lagoon. glaciers, southern Chile. THE WESTERN MARGIN of South America is underlain by a subduction zone, where Pacific Ocean crust passes down towards the east beneath the Americas. At the southern end of this subduction zone, in southern Chile, a mid-ocean spreading ridge intercepts the zone just offshore from the Taitao Peninsula (at around 47?S). This triple junction, where the Nazca, Antarctica and South American plates meet, is an area of massive earthquakes and very rapid crustal deformation (Forsythe and Nelson, 1985). This great tectonic activity is reflected by a correspondingly fast-evolving landscape with the steep fault-controlled margin of the Andes in southern Chile rising from sea level to over 1400 metres in less than 5 kilometres (Plate I). Where the Taitao Peninsula connects with the South American mainland, lies the Laguna San Rafael (46?40'S, 74?00'W) (Fig. 1), a 130 square kilometre tidal lagoon into which the San Rafael Glacier calves (Plate II). The glacier, classified by Lliboutry (1956) as the fifth largest in Chile, flows down the steep margin of the Andes from the North Patagonian Icefield at rates of up to 17 metres per day (Nakajima, 1985). This rapid velocity for a non-surging glacier is a product of the steep western slope of the tectonically active mountains and high snowfall in the accumulation area with annual precipitation at the Laguna San Rafael totalling more than 4000 mm (Enomoto and Nakajima, 1985). Although the San Rafael Glacier is the only branch of the North Patagonian Icefield to reach the sea, the meltwaters from other glaciers source large braided streams with high sediment loads and rapidly changing channel patterns. Various components of this dynamic landscape around the Laguna San Rafael provided the focus for scientific research on the Chile 4B phase of Operation Raleigh in January 1986. The Laguna San Rafael connects with the open fiord, Golfo Elefantes, to the north via a 30-metre deep channel, the Rio Tempanos. At present this is the only exit from the Laguna although in 1940 an attempt was made to open up a second exit via a 2-kilometre long canal through the moraine to the south-west, interconnecting with the Rio Negro. The Rio Negro flows from the bogs of the Taitao Peninsula and joins a series of sediment-laden rivers from the St Quintin Glacier before flowing into the Golfo de Penas. Completion of this canal would provide a sheltered route for boats, avoiding the exposed outer coast of the Taitao Peninsula. The canal was partially completed and there is, at present, renewed interest in finishing the project. The future construction of roads into the region is also planned in order to open up this remote area of the southern Andes to both settlers and tourists. In order for all these schemes to be successfully planned and their environmental impact monitored more information is needed on the morphological evolution of the region and possible local hazards.

Waved Albatross Egg Neglect and Associated Mosquito Ectoparasitism

Seabirds that nest on small, remote oceanic islands escape reproductive losses to predators that affect the breeding ofcontinental birds (Lack 1954, Ricklefs 1969), and food availability is generally thought to limit reproductive success (Ashmole 197 1. Harris 1977. Nelson 1977). In several cases, however, ectoparasites have played a significant role in determining reproductive success of oceanic seabirds (Dutl? 1983 and references therein). Ectoparasites, or the diseases that they may transmit (e.g., van Riper et al. 1986) can cause nestling mortality directly during attacks (Fitch et al. 1946, Curry and Anderson 1987, McKilligan 1987) or indirectly by driving parents from colonies, sometimes en masse (Dully 1983). We add to this small but growing list of ectoparasite-mediated seabird reproductive failures by reporting group desertion of eggs by Waved Albatrosses (Diomedea irrorata), apparently in response to the bites of swarms of mosquitoes. Waved Albatrosses nest at only two sites, both in the eastern eauatorial Pacific: most breed on the southem coast and-inland high points of Isla Espaiiola (Hood Island) (o”N 9O”w) in the Galauaeos Islands. and an additional small colony has existid on Isla La Plata (1% 81”W) (Owre 1976) just west of the South American mainland. We studied the main Espaiiola population in April and May 1986 in conjunction with longterm studies of booby breeding ecology. The island, nesting habitat, and albatross breeding biology are described by Harris (1973). Laying of the one-egg clutch typically extends from mid-April until early June and most fledglings have left the colony by the end of the following December. Adults spend the nonbreeding season away from the breeding colony and, indeed, vacate the entire archipelago (Harris 1973). In 1986 albatrosses were first seen at sea near Espafiola on 8 March and on the island on 17 March, and the first egg was noted on 15 April. Laying proceeded rapidly for the rest of the month, and by the end of April at least 200 eggs had been laid within 3 km of our camp at the eastern end of the island. Eggs hatch 60 days after laying (Harris 1973), so the first hatching was expected in mid-June. April was a month of heavy rain on Espafiola (142 mm), as was the previous February (73 mm). During

Fruit and Consumer Differences in Three Species of Trees Shared by Trinidad and Tobago

Fruit and Consumer Differences in Three Species of Trees Shared by Trinidad and Tobago

A NEW BLIND CAVERNICOLOUS LYGROMMA (ARANEAE, GNAPHOSIDAE) FROM THE GALÁPAGOS ISLANDS

AbstractLygromma anops sp. nov. (Gnaphosidae, Araneae) is described from lava tubes on Isla Santa Cruz, Galápagos, Ecuador. The species appears to have no known close relatives in the Galápagos Islands or on the South American mainland.

Affinities and Recent History of the Avifauna of Trinidad and Tobago

Trinidad was last connected to the South American mainland about 1 1 ,000 years ago. Tobago has been separated for much longer (probably at least 2 million years), but during periods of lowered sea level, the water gap between Tobago and Trinidad may have been reduced to as little as 5 km. The avifauna of the two islands, excluding species that are widely distributed on the South American main- land, can be divided into four distributional categories, Andean, Northern Venezue- lan, Caribbean, and Amazonian-Guianan. The Andean element is very closely related to the montane avifauna of the Cordillera de Caripe and Paria peninsula of north- eastern Venezuela, more so than the latter is to the avifauna of the mountains farther west in Venezuela. The northern Venezuelan and Caribbean elements are small and undifferentiated, and their presence in the islands would be expected on the basis of their present distributions in adjacent areas. The Amazonian-Guianan element is more puzzling, as several of its members are geographically very isolated from the mainland populations; the degree of subspecific differentiation in this group is higher than that in the Andean element. The presence of the Amazonian-Guianan element in Trinidad and Tobago indicates a former extension of the Amazonian-Guianan avifauna up the east coast of Venezuela at a time when the sea level was low. In spite of the fact that Tobago has been an island for about 200 times as long as Trinidad, its avifauna is only slightly more differentiated from that of the mainland. The most likely explanation of this apparent anomaly is that Tobago was so close to the mainland during periods of lowered sea level that it was effectively in biotic contact.

Kiepja and Truganini: The last voices

"Where are the women who sang like cana? ries? There were so many women. Where are they?" asked Kiepja, one of the last surviving Ona Indians, shortly before her death in Tierra del Fuego in 1966 [ 1 ]. Ninety years earlier, Truganini, the last Tasmanian aborigine, had died. She might have asked a question similar to Kiepja's, but in 1876 there were no docu? mentary filmmakers, and Truganini's voice has been lost to us. Nonetheless, the lives and deaths of these survivors from opposite ends of the globe have become the themes of two recent ethnographic films. The story of Kiepja's people is told in The Ona People: Life and Death in Tierra del Fuego, a film by French ethnologist Anne Chapman and Argentinian filmmakers Ana Montes de Gonzales and Jorge Preloran. In 1964, Chapman first visited the islands of Tierra del Fuego off the southern tip of the South American mainland and there began to record the chants of Kiepja, a ninety-year old Ona shaman. In the years that followed she worked with the few other remaining Ona, drawing upon their memories of the past and their reflections on the present. Ona society and culture, however, had long since been destroyed, and the film relies on early 20th century archival photographs to reconstruct pre-contact life and its tragic demise. Kiepja herself had died before the shooting, and by the time of the film's release in 1977, all the other Ona in the film had also died. Before the decimation of the Fuegian Indians began in the 1880s, there were about 4,000 Ona (or Selk'nam), living in small bands and hunting guanaco (a species of American camel), fishing, and gathering. From the 16th until the late 19th century, shipwrecked sailors and occasional ex? plorers and scientists were the only Europeans with whom the Indians had to deal. These early encounters were generally peaceful. Cap? tain Cook visited the islands in 1769, as did Charles Darwin, voyaging on the Beagle in 1832. Darwin was quite stunned by what he saw: "These were the most abject and miserable creatures I anywhere beheld," he wrote of the native population, "one can hardly make one? self believe that they are fellow creatures, in? habitants of the same world." These "degraded savages," he noted, speak a language that "scarcely deserves to be called articulate" [2]. Gold was discovered in the late 1870s in Tierra del Fuego, and a further search was fol? lowed by an invasion of prospective settlers and sheep-farmers from Europe. Pushed from their hunting grounds by white men with re? peating rifles and increasing numbers of sheep, the Ona were hunted down and massacred. Their refuges were the Christian missions and Toby Alice Volkman is Staff Anthropologist with Docu? mentary Educational Resources in Watertown, Massa? chusetts, U.S.A.

Aspects of the Pollination Biology of Three Erythrina Species on Trinidad and Tobago

Aspects of the Pollination Biology of Three Erythrina Species on Trinidad and Tobago

Guyana: Socialist Reconstruction or Political Opportunism?

Guyana has become the second “socialist” republic in the Western Hemisphere after Cuba. The history of how this occurred is an almost classic example of the futility of inept intervention by outside great powers. Prime Minister Forbes Burnham, brought to office in 1965 by Anglo-American intervention that ousted Marxist Cheddi Jagan from power, has turned Guyana from a safe U.S. client committed to a capitalistic economic model into a strident anti-American bastion on the South American mainland, with a politicoeconomic system in theory and increasingly in practice inspired by Marxism-Leninism. The Burnham regime has nationalized all significant foreign firms, declared itself a cooperative socialist republic, and has forged close collaborative links with Cuba, the People's Republic of China, and such left-oriented African countries as Tanzania, Guinea, Angola, and Mozambique.

Anolis Lizards of the Eastern Caribbean: A Case Study in Evolution. I. Genetic Relationships, Phylogeny, and Colonization Sequence of the Roquet Group

Yang, S. Y., M. Soule (Biol. Dept., UCSD, La Jolla, California, 92037), and G. C. Gorman (Biol. Dept., UCLA, Los Angeles, California, 90024) 1974. Anolis lizards of the eastern Caribbean: a case study in evolution. I. Genetic relationships, phylogeny, and colonization sequence of the roquet group. Syst. Zool. 23:387-399.-A phylogeny based upon genetic similarity coupled with information from cytogenetics, behavior, ecological distribution, and geography is developed for the roquet group of Anolis lizards in the southeastern Caribbean region. We postulate that the primary events were stepwise colonization of the three island banks closest to the South American mainland (Grenada, St. Vincent, and St. Lucia). The secondary events were colonization from St. Lucia to the more westerly islands of Blanquilla, and from there to Bonaire; the acquisition of a second on St. Vincent by in situ speciation or by secondary colonization; the colonization of Martinique, Barbados, and the Grenada Bank (the latter for the second time). [Anolis; genetic relationships; phylogeny; colonization.] This paper is an attempt to reconstruct the phylogeny and colonization sequence of a group of insular lizards. The data are genetic similarity estimates for more than 20 loci detected by electrophoresis of water soluble proteins. The results are integrated with information obtained by a variety of approaches during the past decade. Later papers in this series will use the phylogeny herein propounded to help test and develop a general theory of island evolution. Our study is of the Anolis roquet group (Sauria, Iguanidae). The genus is very large (over 200 species); the group under study is well defined osteologically, cytologically, behaviorally, and ecologically. Furthermore, it occupies a discrete set of islands in the southeastern Caribbean region (Fig. 1), a region where no other group of Anolis is represented. The arc of islands that sweeps north and westerly from the continental shelf of South America to the large Antillean island of Puerto Rico is known as the Lesser Antilles. 'Present address: Museum of Vertebrate Zoology, University of California, Berkeley, California. Our area of concern is the southern Lesser Antilles and the islands of Bonaire and Blanquilla, far to the west of the main chain. There are nine species1 in the roquet group distributed on the seven island banks shown in Fig. 1. Each of these banks has endemic forms exclusively. The evolutionary history that we are analyzing is clearly one of sequential colonization between these islands, with presumably little or no input from the mainland following the original colonization, and little or no speciation within an island bank (Gorman and Atkins, 1969). Thorough understanding of the physical geography and geological history of the study area would certainly aid in understanding the evolution of the organisms. We would like to know the maximum ages 1 To avoid semantic problems we are arbitrarily permitting the island bank to define the taxa at the level of species. This seems preferable to the alternative of agonizing over such non-operational criteria as potential fertility of animals on different islands. Admittedly, some of the species are so closely related that they would be referred to as races or subspecies if connecting populations existed.

The Spanish Discovery of the South American Mainland

T HE Spanish Main, that haunt of explorers, exploiters, colonists, and pirates for some three centuries, is commonly supposed to have been discovered by Columbus in I498. On his first two voyages he found only islands; but on his third voyage he visited the mainland of South America, exploring the Gulf of Paria and following the coast of Venezuela westward for more than a hundred miles. In a manuscript now belonging to the Library of Congress there is a narrative that has apparently lain unnoticed for half a century, telling how Columbus sent five caravels south and southeast from Hispaniola and Cuba in search of a certain pearl-fishery. Information about the place evidently came from the natives of Hispaniola, some of whom went along as guides. The course of the expedition is indicated rather sketchily, especially toward the end, where there is some reason to suspect an intentional ambiguity. Only Hispaniola and Cuba are mentioned by name; but the pearl-fishery was clearly on the coast of Venezuela, and the five caravels, before they returned, seem to have made an almost complete circuit of the Caribbean Sea. The time was between September 28 and November I4, and the year is indicated, though by a somewhat roundabout and not absolutely certain method, as I494. This, if authentic, is manifestly important. It dates the Spanish discovery of the mainland of America four years earlier than has commonly been supposed. It goes far toward explaining the famous world map drawn by Juan de la Cosa in I500, which has long been under suspicion of being later in date because it includes the western shore of the Caribbean and depicts Cuba as an island. It throws light also on the alleged effort of Columbus in I498 to conceal his own discovery of pearls, an effort that is held by some to have been the turning point in his whole career and to have caused his downfall from royal favor. The history of the study of Columbus and his period is strewn with the wrecks of forged or fanciful theories regarding one matter or another; and a narrative like this one, offering several unexpected possibilities of historical importance, requires to be scrutinized with the utmost care. I have made elsewhere some initial efforts to examine the credentials of the manuscript in which it is found, and also to estimate its relation to the official report of Columbus concerning his

THE BIRD FAUNA OF THE GALAPAGOS ISLANDS IN RELATION TO SPECIES FORMATION

Summary.The Galapagos Islands possess a peculiar and highly characteristic fauna and flora. The abundant bird and reptile populations are nearly all of endemic species; of the land birds only two species occur elsewhere than in these islands. Studies bearing upon the origin of the Galapagos fauna have led to diverse conclusions; scrutiny of modes of variation has revealed some curious situations. The Galapagos have been variously regarded as the surviving remnants of a land‐mass, now sunken, that was formerly connected with the American mainland, and as oceanic islands that have appeared above the ocean as the result of volcanic upheaval. Study of the birds is confirmatory of the latter view. The avifauna is clearly not derived from the South American mainland directly to the eastward. Of the marine species there are one or two of southern origin, borne northward on the cold Humboldt current, and there are others which constitute local forms of species that are of world‐wide distribution. There is an important element definitely recognisable as of West Indian derivation, and others may have originated from the same source. There are a few species that clearly are not of West Indian ancestry, and there are a number that are too widely differentiated for recognition of their immediate affinities. The hypothesis is advanced that the inception of the Galapagos avifauna took place in a period when North and South America were separated by the sea; the relationship of the faunas of the West Indies and the Galapagos is to be regarded in the same light as relationships from one to another of the West Indian islands. The bird population of the Galapagos, abundant as regards individuals, is, as regards representation of different groups, of the sparse and miscellaneous character to be expected of chance‐controlled wanderers to distant islands.Conditions are uniform enough throughout the archipelago, so that, with much local variation, each island contains a fair representation of the same general assemblage of species. Trends of variation are seen in arrested stages of plumage in certain species, in a possible tendency to melanism in others. There are many variants of these situations. The outstanding group of birds is the endemic family, the Geospizidae, including 37 species and sub‐species out of the entire list of 89 breeding birds. Extensive variation and complicated relationships within this family are such as can probably not be duplicated in any mainland stock of birds. The observed variation presents difficulties to classification, and certain trends of development seem to act independently of natural selection. The Geospizidae afford a fine example of diversification unhindered by competition.

Fluorescein dyes as bacterial stains

The Lesser Antillean island arc holds a favorable position on the route from the South American mainland to the Greater Antilles, stimulating colonization processes, linking two major centers of cultural development and encouraging the establishment of interconnecting interaction networks.Both the South American mainland and the Greater Antilles have been of great importance for the socio-cultural development of the smaller islands of the Lesser Antilles during the entire pre-Columbian era.The discontinuous distribution of natural resources and a great variability in the availability of raw materials is regarded as one of the driving forces behind the highly mobile nature and diversified procurement strategies of the Archaic Age fisher-collector communities and the establishment and maintenance of intensive contact networks of the Ceramic Age horticulturalists. Mobility patterns and material distributions evidence that these networks changed through time probably as a result of the shifting and expansion of group territories, fission and fusion of local groups and changing socio-political organization.During the Archaic Age the region was sparsely inhabited by people adopting an annual mobility cycle encompassing multiple islands, each representing a unique resource patch within the environmentally heterogeneous region.During the Ceramic Age more permanent settlements were located on the coast as well as in the interior of islands in diverse ecological settings, people taking on a broad-spectrum subsistence economy and living in villages.The inhabitants of the Windward Islands or southern Lesser Antilles maintained intensive contacts with the South American mainland evidenced by highly symbolic representations on ceramic and lithic artifacts recalling their origin and the enduring exchange of exotic objects. Ties with the mainland are secured until colonial times with the intrusion of the so-called ‘Island Caribs’ who hold the assertion to have conquered the islands out of the Guianas.The Leeward and Virgin Islands, i.e., the northern Lesser Antilles, on the other hand, show an increase in the number and size of ideology-linked Taino artifacts over time demonstrating that their inhabitants interacted predominantly with people on the islands of the Greater Antilles emphasizing their incorporation into the realm of the Taino cacicazgos during the last centuries prior to colonization. Despite partaking in these regional interaction spheres, both the northern and southern Lesser Antilles are characterized by local cultural developments and obviously participated in more localized networks as well, that expanded and contracted through time.After European colonization the native population of the Lesser Antilles was decimated by diseases and slavery. Nonetheless, missionary accounts from the mid-seventeenth century still attest to a sizeable indigenous population and Amerindians survive to this day on Dominica and several other southern Lesser Antillean islands.

Notes on blood-sucking flies in Grenada

Grenada is the southernmost of the string of Islands composing the Lesser Antilles, if we except Trinidad and Tobago, some ninety odd miles further south, which lie close to the South American mainland of Venezuela. Geologically the Island is volcanic; basalts, lavas, cinder beds, gravel beds, agglomerates, various earths or clays forming the soil and subsoil of valleys, slopes, ridges, cones and craters, from sea-level to some 3,000 feet of elevation.

On Some Interesting Cases of Migrations of Marine Fishes on the Coast of Venezuela at Carupano

CARÚPANO is a thriving seaport on the northern coast of Venezuela, midway between the peninsulas of Araya and Paria, in lat. 10° 14′ 15″N., and long. 63° 18′ W. from Greenwich, and therefore in close vicinity to the channel which leads from the Atlantic into the Caribbean Sea between Tobago and Grenada on the one side, and Trinidad and the South American mainland on the other side. Through this channel enters the great western current of the Caribbean Sea, running at the rate of about one mile and a half an hour, though not with much regularity. The coast-line forms the western prolongation of the northern shore of Trinidad, trending almost due west. The water is rather shallow to a considerable distance from the land, the 100-fathom line due north of Carúpano being about 60 miles off the shore,1 which gives for the sea-bottom a gradient of but 1.67 per 1000.2