Biogeographical Research Research Articles

The palaeozoogeography of Oligocene to Recent marine Ostracoda from the Neotropics (mid- and South America) and Antarctica

Classic biogeographical research has shown that the continent of South America supports a diverse and priceless biota, of which ostracods are an important component. The distribution patterns of Oligocene to Recent shelf ostracods, from the Neotropics to Antarctica, are explained in terms of dispersal and vicariant events. The quantitative examination of a newly constructed database, containing over 140 genera, has allowed the measurement of generic similarity and endemicity between biotas of different geographical regions. The measurement of these parameters has aided the construction of a series of palaeoendemicity and communality maps. These maps emphasise changes in the spatio-temporal distribution of mid to Late Tertiary ostracods, and can aid in the recognition of abiotic mechanisms that modify genera distribution. It has been demonstrated that changes in the oceanic currents and water-mass temperature are significant in the formation and maintenance of zoogeographical domains in the Oligocene–Recent of the Neotropics and Antarctica. South America was an important centre of origin for ostracods during the Oligocene, however, few genera appear able to disperse northwards towards the Caribbean. The migratory success or failure of benthonic ostracods is closely linked to oceanographical and climatic conditions, and their physiology. Within the Meso-American region, filter and corridor pathways have allowed rapid dispersal of shallow water ostracods which has lead to decreased endemism. Although a distinctive ostracod assemblage was established in the Oligocene of Antarctica, the expansion of the Drake Passage permitted a new suite of cryophilic genera to emerge on the continent during the ?Mio-Pliocene. Within the Meso-American region the alteration of oceanic circulation patterns, subsequent to the closure of the Panamanian portal, may have initiated the development of a `proto' Panamanian Province in the Early Pliocene.

Biodiversity: the scene in Australia and the role of the Australian Biological Resources Study

It is estimated that Australia is home to more than 1 million species, less than 15% of which have been described. No estimate is given for parasites, but brief speculation on the potential is presented. The Commonwealth Government has a clear role in funding biosystematic research in Australia in support of its Natural Heritage Trust programmes, the National Biodiversity Strategy and its responsibilities under the Biodiversity Convention, and in order to maintain adequate taxonomic capacity. As a Government programme of Environment Australia, the Australian Biological Resources Study has disbursed around A$12 million towards taxonomic and biogeographic research on animals and Protozoa. Approximately 10% of this amount has gone towards parasitology. With funding for the Study being in a somewhat parlous state, it is argued that priorities for research funding need to focus clearly on issues of national significance as expressed in Government policies, strategies and environment programmes. In addition to scientific merit, research questions and projected outputs in project applications for funding should be justified in terms of meeting the needs of end users in conservation management, primary industry, and the wider biological research community.

The epidemiological significance of islands

Islands have proved fruitful laboratories for biogeographical research from Darwin and Wallace onwards. We examine here the significance of Black's work ( Journal of Theoretical Biology, 11, pp. 207–211 (1966)) on island epidemics. His original data on measles outbreaks on 19 islands over the 15 year period from 1949 to 1964 are reanalysed, and the confounding effects of island accessibility and population density upon estimates of the population threshold for measles endemicity are illustrated. Using later data, we extend Black's analysis into the post-1965 measles vaccination era both for the islands he studied and for 22 others, and then explore the potential of intra-island comparisons. Although Black confined himself to measles, this paper suggests that his ideas are extendable to a wide range of other infectious diseases. Island epidemiology has implications both for practical questions of disease control and for academic questions of the persistence and origin of diseases.

Biogeographic patterns of tropical south American scorpions

Based on the personal biogeographic research of the author a review of the major patterns of distribution and differentiation of tropical South American scorpions is proposed in this paper. The principal corridors of distribution are defined and examples are given to illustrate the cases of monomorphic, polytypic, mosaic polymorphic, clinal polymorphic and ochlospecies polymorphic species for both savanna and rainforest. Some examples of disrupted distributions of genera and species in forest and savanna formation are added.

Some results of biogeographic research on meadows in the Dyje-Svratka basin in the Czech Republic

Some results of biogeographic research on meadows in the Dyje-Svratka basin in the Czech Republic. The paper shows one example of biogeographic “inventory” of natural ecosystems in an unflooded meadow in the Dyje-Svratka basin. It is part of the complex physio-geographic research of the Geographic Department of the Masaryk University in Brno aimed at gaining a basis for territorial interpretation of ecological regularities and territorial application of general ecological optimizing principles. A segment of biocenosis of Ulmi-fraxineta carpini has been analyzed (Zlatnik 1956).

Seed banks as a neglected area of biogeographic research: a review of literature and sampling techniques

The article highlights a comparatively neglected area of biogeographical research - seed banks and the distribution of seeds in the soil. The article reviews some of the relevant literature on seed banks and the methods for their study. Attention is focused on aspects of seed banks of particular relevance to biogeographers, with detailed examples drawn from seed bank studies in both temperate and tropical environments. In the review of the seed bank literature, the topics covered include the seed banks of successional communities and the size of seed banks in different vegetation types. The species composition of seed banks in different plant communities is discussed, particularly the degree of correlation between the species composition of seed banks and associated ground flora. The relationships between seed persistence, depth of burial in the soil and soil properties, such as moisture and pH, are explored. Seed bank heterogeneity is examined and a number of studies which have attempted to describe and measure the spatial variability of seed banks are summarized. Ways of classifying seed banks in terms of seed bank strategies are explained. The role of seed banks in conservation is discussed, for example in restoration projects, where preferred species have been lost from the vegetation but survive in the seed bank. The relevance of seed banks for the conservation of rare species and in landscape management is considered. Lastly, the contribution of seed banks to the recovery of vegetation following disturbance in various plant communities is discussed. In the review of seed bank sampling techniques, the subjects considered include methods of sample collection, the sampling intensity required for reliable estimates of seed density, a consideration of the relative merits of random and systematic sample distribution, as well as the importance of the timing of sampling. Various methods for the estimation of seed numbers in samples are appraised; these either involve extraction of seeds from the soil, followed by seed identification or enumeration by germination and seedling identification. Problems of analysing seed bank data are considered and several useful techniques for data analysis are suggested. Finally, the article draws attention to areas of future seed bank research for biogeographers and plant ecologists.

Ecological Disturbance and Nature Tourism

Recent research in biogeography presents a convincing case that natural disturbance is not an aberrant influence but is common to many biological systems. Human changes in the environment can have surprising and profound effects on the impacts of natural disturbances. If recent efforts to use nature tourism to conserve natural resources are to succeed, such development must incorporate ecological insights into the interaction of natural disturbance with social and biotic systems. Relevance of a nonequilibrium ecological model for environmental planning is illustrated for two barrier beaches on the Yucatan peninsula. THE purpose of this article is to consider the role of disturbance as a crucial ecological consideration in landuse planning for nature tourism. Incor- poration of ecological insights into the environmental-planning process offers hope for rational and sustainable development. Nature tourism has been proposed in recent years as a solution to the dilemma that developing countries face in conserving their biological heritage and concurrently im- proving the economies of local human settlements. In Mexico, nature tourism has become a favored mechanism for devel- opment, especially on the Yucatan peninsula. Recognizing the immense value of its coastal natural communities, Mexico has recently established several large biosphere reserves to preserve natural resources and to accom- modate and support human settlements. The experience of sprawling, high- impact Cancun, with more than one million visitors annually, has encour- aged the government to reassess its development goals. One example of Mexican openness to sustainable conservation-development projects is the innovative, cooperative effort of Mexico, Belize, Guatemala, El Salvador, and Honduras to establish Ruta Maya, a low-impact design to promote tourism based on natural and archaeological treasures (Garrett 1989). In the Yucatan, two long, relatively pristine barrier peninsulas, Rio La- gartos and Celestun, are being identified as opportune sites for nature tour- ism. Both have high conservation value and were designated special bio- sphere reserves by the government in 1979 because of their floral and faunal diversity. Both have small human settlements based on fishing and salt extraction. The protection concept known as the Mexican modality, in which local villages can coexist with both conservation and tourism, is an ambitious development plan.

Zooarchaeology and the biogeographical history of the mammals of Corsica and Sardinia since the last ice age

AbstractThis paper presents the main results of a 10‐year zooarchaeological study on the origin of the present‐day terrestrial mammals of Corsica. Thousands of teeth and bones from Corsican archaeological sites comprise an almost complete succession from the end of the Pleistocene (c. 10,000 years BP) to the present. Human activities brought about the extinction of the entire autochthonous mammalian fauna and the gradual introduction of more than 25 taxa which constitute the present wild and domestic fauna. Such a complete turnover has also been recorded on other large Mediterranean islands and on some of the smaller ones. Preliminary data indicate how these events may have occurred in Corsica. This article emphasizes the important role which zooarchaeology can play in biogeographical research.

What can vicariance biogeographic models tell us about the distributional history of subterranean amphipods?

Because of taxonomic diversity, geographic isolation, and other considerations, subterranean ground-water amphipods would appear to make excellent candidates for biogeographic studies. Limted dispersal ability in combination with local endemism makes it likely that vicariance models will generally offer better explanations for present distribution patterns of subterranean amphipods than scenarios based on centers of origin and dispersal. Vicariance biogeography demands a knowledge of both phylogeny and area relationships, which are typically shown on biological area cladograms. To date most biogeographic studies on subterranean amphipods have been limited to cladograms of single taxonomic groups. Although useful in showing possible relationships between areas and nested subsets of taxa, these single taxon studies do not consider covariant patterns among different groups. However, in order to be fully effective, future biogeographic research will have to focus on analyses of congruence between biological area cladograms of amphipod taxa and other subterranean crustacean groups, such as isopods. To date many covariant distributions among groups of subterranean crustaceans have been recognized but not yet analyzed for congruence.

Earthworm Population Dynamics and Contribution to Nutrient Cycling During Cropping and Fallow Phases of Shifting Agriculture (Jhum) in North-East India

The impact of climate change on species distribution is a hot issue in biogeography research. This study utilized the constructive species Stipa purpurea as the research object, which was widely distributed in alpine meadow of the Tibetan Plateau, investigated its distribution in the Tibetan Plateau through the field survey and herbarium search, and used MaxEnt model to simulate its historical, current and future distribution trends to analyze its distribution pattern in each historical period and explore the cause of species distribution changes. Research results showed that diversity of Stipa species in alpine grassland of the Tibetan Plateau was high, its main distribution area was the hinterland of the Tibetan Plateau and areas along the Himalaya, and its distribution was strongly affected by precipitation of warmest quarter, precipitation of wettest quarter and annual precipitation. According to the distribution pattern of S. purpurea in the Last Glacial Maximum, and geographical and geological features of the Tibetan Plateau, this paper proposed that: North Tibet core area of South Qiangtang and Ali region of west Himalaya mountainous area were the core area of the potential distribution for S. purpurea, since these regions could provide more suitable habitats for S. purpurea than other regions and be the refugia where the current S. purpurea was migrated and differentiated from. The presence of refugia may contribute to the understanding of related issues of the alpine plants' origin and differentiation in the Tibetan Plateau.

Simulation of regional soil moisture deficits on a European scale

A simple deterministic simulation model for landscape-scale soil water deficits has been developed. Standard weather station data are used to estimate ‘daily’ precipitation and actual (regional) evapotranspiration (AET). The balance is added to soil moisture, which is accounted by a simple bucket model. AET is the daily integral of the lesser of supply and demand: supply is governed by current soil moisture, demand by estimated net radiation and temperature. The model estimates geographical patterns of soil water deficit at a scale suitable for comparison with the distributions of plant species and vegetation types. The model provides a way of quantifying soil moisture stress in biogeographical research.

Unexpected microfaunal communities within the Triassic Tethys

Abstract Modern research has demonstrated a remarkable uniformity in Triassic faunas throughout the Tethyan region. This is true not only for planktonic and pelagic elements but also for vagile and sessile benthic organisms, and involves a surprisingly large number of species of macro- and microfauna, including numerous zone fossils. In this work, further striking microfossil examples are selected from potentially important groups that have been little utilized previously for biogeographical research.

Information available within the PRECIS data bank of the National Herbarium, Pretoria, with examples of uses to which it may be put

The contents of the computerized information storage and retrieval system (PRECIS) of the National Herbarium, Pretoria (PRE) are described at length mainly by means of frequency histograms of descriptor codes. The frequency distributions found are discussed in the light of the history of the herbarium, the geography of the area and the habits of plant collectors. Two uses of PRECIS are illustrated by example. Firstly, the flowering phenology of Eragrostis capensis, Themeda triandra and Heteropogon contortus is plotted and, secondly, the route followed by Dinter in South West Africa/Namibia from December 1933 until March 1935 is described. It is concluded that the system should be o f particular use in revisionary studies, regional floras and biogeographic research.

The J. H. B. Bookshelf

Because the subject of biogeography cuts across so many scientific disciplines, one might wonder whether it would be possible to offer a unified account of its history. But Janet Browne has done exactly this, and her coherent portrayal of biogeographical thought from Linnaeus to Darwin adds a new dimension to preand early evolutionary history of biology and geology. She begins with the seventeenthand eighteenth-century conception of the distribution of animals over the earth from Noah's Ark, and with Linnaeus' and Buffon's differing views on single versus multiple points of creation. With the work of Alexander yon Humboldt and Alphonse de Candolle in the early nineteenth century and their new statistical methods of "botanical arithmetic," the study of plant distribution became a science. At the same time geologists like Georges Cuvier and Adolphe Brongniart were turning to fossil distribution studies, and de Candolle pioneered the field of paleobotany. Browne explains how among geologists biogeographical data were interpreted as processes, whereas taxonomists looked instead for patterns of distribution. As the question of the origin of species assumed increasing importance in the nineteenth century, it became a central issue in biogeography. Nontransmutationists such as Edward Forbes, Louis Agassiz, and Joseph Hooker (in his early work) attempted to account for representative species through nonevolutionary means. But for Alfred Russel Wallace and Charles Darwin the notion of organic change played a key role in their perceptions of geographical distribution. In the last two chapters of her book Browne discusses Wallace and Darwin in detail, adding a new perspective to the development of their evolutionary theories. With their work the separate strands of biogeographical research in botany/zoology and in geology/paleontology were interwoven within a new specialized field of natural history. Browne's study is extremely readable, and its major themes are well

Equilibrium Theory of Island Biogeography and Ecology

Department of Biological Science, Florida State University, Tallahassee, Florida 32306THE BIOLOGICAL IMPORTANCE OF ISLANDSOceanic islands and archipelagoes are intrinsically important to biologists; 5% ofthe land surface of the earth is insular, and if South America, which has been anisland throughout most of its existence, is included the figure rises to 19%. Signifi-cant portions of the evolutionary histories of many economically and biologicallyimportant species occurred on oceanic islands, and if the earth were not liberallysprinkled with isolated bits of land in addition to the world continent, its biotawould be much poorer.But the intrinsic importance of islands, scientific or economic, has not inspiredthe intense research in island biogeography which justifies this review of recentadvances. Rather it is the realization that oceanic islands are paradigms for geo-graphic entities ranging in size from tiny habitat patches (52, 53) to continents (86,92, 112) or even the entire earth (74). It is almost a platitude that Darwin’s observa-tions in the Galapagos Archipelago and Wallace’s in the Malay Archipelago crystal-lized the then nascent concept of organic evolution by natural selection (13, 110),and many other classical evolutionary advances rest originally on insular observa-tions. Because islands are so clearly isolated from other land masses, island popula-tion data contributed heavily to the realization that most speciation is allopatric(54). Wallace’s Malaysian observations allowed strong inferences about changingsea levels, past land connections, and the position of a line separating two greatbiogeographic provinces (110). Insular isolation is important ecologically becauseit allows us to be virtually certain that an organism encountered on an island is atrue nesiote. Consequently, problems in Community structure and function, such asthe distribution of individuals into species or the trophic relationships among popu-lations, are more readily attacked in an island setting; any organism found there isassuredly a member of the biotic community.161

Some Problems in the Biogeography of Land Areas

Neglected research areas in biogeography are suggested. Biocenoses, or biotic communities, are the basic units with which the biogeographer should be concerned. Biogeographic research should now pass on from the study of species to integrated work on entire biocenoses, the interdependence between biocenoses and their biotopes, and the study of biocenoses in their comparative geographical context. Biogeography should be concerned with the structural features of biocenoses and their changes through time and through space. Of particular importance at the present time is the geographical aspect of man's influence on biocenoses. The discussion is limited to terrestrial biocenoses because, in the author's judgment, this aspect of biogeography has been lagging behind research on aquatic biocenoses.

COEVOLUTION OF MUTUALISM BETWEEN ANTS AND ACACIAS IN CENTRAL AMERICA.

The purpose of this paper is to discuss the coevolution of one of the more thoroughly studied mutualistic systems in the New World tropics: the interdependency between the and their ant inhabitants. This system has recently been described in detail in respect to one species of plant, Acacia cornigera L. (Mimosoideae; Leguminosae), and one species of ant, Pseudomyrmex ferruginea F. Smith (Pseudomyrmecinae; Formicidae), and shown experimentally to be a case of mutualism (Janzen, 1966a). In this species pair, the ant is dependent upon the acacia for food and domicile, and the acacia is dependent upon the ant for protection from phytophagous insects and neighboring plants. The literature dealing only with the New World tropical (Acacia spp.) and their ants (Pseudomyrmex spp.) has been re-evaluated by Janzen (1966a) and will not be discussed further in a review sense. The higher plants that commonly have ant colonies living in them have long been termed myrmecophytes. Ants living in plants range in habit from fortuitous usage of a plant cavity to highly complex interaction systems between the ant and the higher plant. The ant-acacia system represents this latter extreme, and the acacia is by any definition a myrmecophyte. A review paper on the subject of myrmecophytes is in preparation. In the present paper, plants with ants living in them will be called ant-plants; the ants will be called plant-ants. The swollen-thorn acacias are those with 1) enlarged stipular thorns normally tenanted by ants, 2) enlarged foliar nectaries, 3) modified leaflet tips called Beltian bodies (eaten by the ants), and 4) nearly year-round leaf production and maintenance even in areas with a distinct dry season (Fig. 1). Swollen-thorn have been shown experimentally to have a virtually obligate dependency on 1 Contribution No. 1308 from the Department of Entomology, The University of Kansas, Lawrence. This study was supported by National Science Foundation Grant GB-1428 to the University of California, Berkeley (Dr. R. F. Smith), University of California Associates in Tropical Biogeography Research Grants 66 and 81, and The University of Kansas General Research Grant 3173-5038, and also is a by-product of National Science Foundation Grant GB-91 (Dr. C. D. Michener).

CHARLES C. ADAMS, 1873–1955

1HARLES C. ADAMS was born in Clinton, . Illinois, on July 23, 1873, and died at Albany, New York, May 22, 1955. He obtained a bachelor's degree at Illinois Wesleyan College in 1895, and the degree of Master of Science at Harvard in 1899. He then studied at the University of Chicago from 1900 to 1903, where he took his doctorate. At Chicago he was at the center in which American ecology and ecological biogeography were being developed under the leadership of Henry Chandler Cowles and his students. There also he came under the influence of Rollin D. Salisbury, an extraordinarily inspiring teacher in the earth sciences. For a period of years following his graduate work he held varied research and curatorial positions in universities and other institutions in the Middle West, and in 1914 he took a position as Forest Zoologist at the New York State College of Forestry at Syracuse. Adams remained in the New York State service until his retirement in 1943. He directed the Roosevelt Wildlife Experiment Station from 1919 to 1926, and in the latter year became Director of the New York State Museum at Albany. Soon after leaving Chicago he had become interested in museum work, and this was a primary interest throughout the remainder of his life. He saw in the field of ecology what he considered to be an outstanding medium for teaching and museum demonstration in the natural sciences. Many of his later publications were in support of this idea. A bibliography of his publications totals 154 titles. Their subject matter is extremely varied, from research papers on fresh water mollusks to such things as the Application of Biologic Research Methods to Urban Areal Problems. He was active in several scientific societies, and was one of the early members of the Association of American Geographers. He served as second vice-president of the Association in 1913, and as vice-president in 1927. In 1916 he was one of the founders of the Ecological Society of America, and was its president in 1923. He had a large correspondence, and accumulated an extensive personal library of books and reprints. All of this material has been given by his daughter to Western Michigan College at Kalamazoo, where it forms the nucleus of what has become known as the Charles C. Adams Center for Ecological Studies, located in the Department of Biology at that school. There were in his files at the time of his death sizeable residues of reprints of his own published papers, even of the earlier ones. The recently established Center, through its director, Dr. Daniel F. Jackson, has made these reprints freely available to institutions and individuals. It is probable that Dr. Adams was most widely known for his publications in the field of animal ecology, for his attempts to apply ecological research methods to the problems of human communities, and for his continual emphasis upon ecology as a teaching mechanism. The conceptual difficulties involved in the construction of rationales in all these areas were, and are, formidable; and he met them with integrity and humor. Appreciations of his efforts with them, published since his death, are evidence of the high esteem accorded him by ecologists.' On the other hand, some of his earlier research in biogeography may, in larger perspective, prove to be of equal significance. One of his major research papers, published as a Memoir in the National Academy of Sciences in 1915, is on the Variations and Ecological Distribution of the Snails of the Genus lo. This genus of snails inhabits only the upper reaches of the Tennessee River in southwestern Virginia, eastern Tennessee, and northern Alabama. Adams did a great deal of field work on them himself, and had access to a large quantity of earlier collections. He made careful studies of variations within species, and related these variations to distribution patterns. From his studies he was able to define certain dines of variation within and among the species occurring at various levels in the valleys of the rivers inhabited by the