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After a short introduction on the reef development during the Late Palaeozoic, the tectono-stratigraphic history of the Cantabrian Mountains (northern Spain) during the Carboniferous is discussed, with an emphasis on the tectonically active Pennsylvanian (i.e., Late Carboniferous). The reef-bearing Valdeteja, San Emiliano, and Cuera formations are briefly described, and their brachiopod faunas are discussed with special emphasis on adaptations to a reef environment. The brachiopod faunas are compared with similar faunas from carbonate-platform deposits with reef structures of Mississippian (i.e., Early Carboniferous) age from Northwest Europe (the British Isles in particular), with Pennsylvanian-Permian faunas from the Alps, Urals, Spitsbergen and Arctic Canada, and with Permian reef faunas from Texas (USA). The Bashkirian brachiopod faunas of the Valdeteja Formation resemble the similarly aged Hare Fiord fauna from Arctic Canada most. This makes one wonder whether the connection between the Palaeotethys and Arctic Canada was through the Urals sea and Arctic, as generally believed, or whether there was another connection from the Cantabrian Mountains to the north along eastern North America. [ABSTRACT FROM AUTHOR]

We studied morphological and molecular characters in Podarcis bocagei and P. hispanica lizards in the Ria de Arosa archipelago in coastal Galicia, Spain. Contrasting published information about insular distributions indicated that morphological species identification is problematic. Instead, we identified 145 lizards from 13 islands and several mainland populations by a panel of partially diagnostic nuclear protein loci and through the DNA sequencing of a stretch of 297 base pairs (bp) of the mitochondrial cytochrome-b gene. Correspondence between the molecular identifications was complete, with the exception of two lizards that carried P. hispanica mitochondrial DNA in a P. bocagei nuclear background. The combined results indicate past hybridization events and the oversea dispersal of a female lizard over a distance of about 500 m. Fourteen morphometric and 12 meristic characters were measured in 187 lizards from 15 islands and several mainland reference populations. Multivariate analysis revealed significant differences between sexes and between species. Two island populations for which no molecular data were available were identified as belonging to P. bocagei from morphology. Locally, P. bocagei and P. hispanica have an essentially parapatric distribution, with P. bocagei in the northeast and the islands of the inner Ria, and P. hispanica in the southwest and the islands of the outer Ria. Common patterns for island populations are an increase in absolute size, a decrease in three relative head width parameters, and a lower nuclear genetic heterozygosity than on the mainland. No correspondence was observed between morphological and molecular patterns of intra-specific differentiation. Also, linear distance between populations did not help to explain the results. Because the Ria de Arosa is a flooded river valley, the local bathymetry reflects the order in which the islands have become isolated from the mainland since the sea-level rise started c. 14,000 years ago. However, the temporal order of isolation was not associated with the pattern of population differentiation. The island populations of P. hispanica seem to have diverged over multiple genetic and morphological axes, with no obvious relationship to inter-population distance, coastline history, island ecology, or species habitat preferences. The results indicate that genetic drift is the main force driving in population divergence. Oversea dispersal, that is gene-flow, appears insufficient to counter the morphological differentiation between some island populations. Hypothesis on the biogeographical history of P. bocagei and P. hispanica in western Galicia are discussed. [ABSTRACT FROM AUTHOR]

The clearest examples of dwarfism and gigantism on islands are found in the fossil record. They form part of unbalanced faunas, which attest that only a few non-volant mammals were able to reach the island. Pygmy elephants and giant rats evolved in the isolation of these insular environments. Thus, the telltale signs of an insular fauna can be used to deduce the island's palaeogeography. The faunas from the Gargano (Italy), a region presently forming part of the mainland, contain various giant rodents and a giant insectivore indicating that the Gargano was an island during the Mio-Pliocene. On the other hand, the Miocene and Pliocene faunas from the present-day Greek islands are balanced, indicating that they were connected with the continent at that time. The Pleistocene faunas from the same islands, however, are unbalanced, showing they lived in an isolated insular environment, and thus the faunas bear witness of the timing of tectonic processes. The same patterns as in the Mediterranean can also be found on the Indonesian islands. The islands of the Sunda shelf, which during glacials are connected to the mainland, have balanced faunas. In Wallacea we find the familiar pattern of dwarfed large mammals and giant murids in unbalanced faunas. The island of Flores even yielded remains of Homo floresiensis, a small hominin that shows that Man as well could be subject to the pattern of insular evolution. [ABSTRACT FROM AUTHOR]

Islands are broadly defined as inhabitable areas surrounded by a hostile environment, which makes island a relational term. The various kinds of islands from a snail's perspective are listed, with examples of species occurring in those places. Isolation may be brought about by surrounding water, ice, or a variety of other ecological factors. Palaeoislands have existed in the geological past but ended their existence afterwards, for example by a lowering of sea level. Since there are by definition no contact zones between islands, a species or subspecies concept based on reproductive isolation under natural circumstances cannot be applied there. It is concluded still that archipelagos constitute the most important reservoir of gastropod diversity, with a high degree of endemism. Some predictions of evolutionary theory about speciation and adaptation are tested in an island setting, with also palaeoislands taken into account. Allopatry may result in differentiation and speciation, but whether, when, and how this happens differs considerably among the taxa. The adaptation to a particular island habitat, for example a cave, may follow quite different routes, probably because of the random mutations that enable the process. [ABSTRACT FROM AUTHOR]

The Eocene-Oligocene transition was an important period of global extinction. Jamaica is used as an example of how local influences in both the terrestrial and shallow marine realms contributed to the global pattern. In the early Middle Eocene, Jamaica had a coastal terrestrial fauna that included a rhinoceros, amphibious prorastomid sirenians, an archontan, eusuchian crocodiles, and an anolid? lizard. Before the late Middle Eocene, the island was completely submerged, drowning non-amphibious members of this fauna. This extinction was apparently driven by local changes of relative sea level. [ABSTRACT FROM AUTHOR]

The evolutionary biology of long-lived lake bivalves, a group that has received comparatively little attention compared to, for example, gastropods and ostracods, is reviewed. Bivalve faunas of different (fossil and extant) long-lived lakes are characterised, and evolutionary aspects, such as the paucity of radiations of common cosmopolitan freshwater groups like sphaeriid and corbiculid clams are addressed. Special attention is given to the corbulid radiations in Miocene Lake Pebas of Western Amazonia. The ability to evolve morphological and ecological characteristics in long-lived lake biota that exceed the range of variation of their relatives in "ordinary" (non-long-lived lake) environments is discussed and termed "supralimital evolution". Several examples are discussed that show that such evolution is facilitated by the availability of empty biotopes after ecological crises in ecosystems at the onset of long-lived lake stages that are stable on ecological time scales. Implications for uniformitarian applications of long-lived lake biota are discussed. [ABSTRACT FROM AUTHOR]

The central part of the Indo-West Pacific (IWP) harbours the highest marine biodiversity, but only few data of its origin are available. In this paper the Cenozoic records of large benthic foraminifera are reviewed. Since many groups need species level revision, the occurrences of genera were reviewed based on records from literature. It is acknowledged that using genus level data is susceptible to differences in interpretation between authors, but the observed patterns are tested against morphological disparity and the number of taxa observed in a single locality. The analyses show a longitudinal shift in diversity from the western Tethys in the Eocene to the central IWP in the Miocene and younger. Oligocene faunas were relatively homogenous between these two regions. During the Eocene radiation occurred in the western Tethys, and abundant and often stratigraphically long-ranging species migrated east and reached Indonesia. This pattern reversed from the Late Eocene onwards, continuing in the Oligocene, and especially the Miocene. However, although the same genera were observed in Oligocene deposits from the western and eastern Tethys lineages showing similar morphological trends evolved independently and at different rates in the two regions. The observed patterns compare very well with the availability of suitable habitat in shallow tropical seas, and are fine-tuned by environmental parameters such as temperature and nutrient availability. [ABSTRACT FROM AUTHOR]

The ranges of many tropical marine species overlap in a centre of maximum marine biodiversity, which is located in the Indo-Malayan region. Because this centre includes Malaysia, the Philippines, Indonesia, and Papua New Guinea, it has been named the East Indies Triangle. Due to its dependence on the presence of coral reefs, it has recently been referred to as the Coral Triangle. Because these reefs are severely threatened by human activities, large-scale nature conservation efforts involve the establishment of a network of Marine Protected Areas (MPAs), for which it is important to know the position of this diversity hotspot. Although it is recognized where this centre is located approximately, it is unclear where its exact boundaries are. Only in a limited number of biogeographical studies, ranges and diversity centres of Indo-West Pacific (IWP) taxa have been presented. In this regard, tropical corals, marine fishes, and molluscs have received most attention. However, just for reef corals alone several different diversity centres have been proposed. The boundaries of the centre are important for reconstructing the processes that were responsible for its present shape. They may relate to the area's climatic and geological past or to the dispersal of larvae by currents in combination with ecological constraints that may prevent their settlement. Especially, in brooding organisms, without larvae or other propagules performing long-distance dispersal, isolation mechanisms may have been important for speciation and species diversity. Information on sea-level fluctuation and the past position of coastlines and data on molecular variation between and within species may help to support models that explain the present position of the centre of marine biodiversity. A detailed biogeographical study of the Fungiidae, a family of corals that disperse through larvae, is used to present a model for a diversity centre and the processes that may have caused its present position. For each species, presence-absence data were obtained from many areas in order to plot their distribution patterns. Since several species do not occur on Sunda shelf reefs, the western part of this diversity centre may have been moulded along the Sunda shelf margin since the end of the LGM (17.000-18.000 BP). Species diversity appears to be distributed unevenly among areas within this centre, which depends on habitat heterogeneity, such as cross-shelf gradients in salinity and turbidity. Eventually, the distributions of several model taxa need to be compared in a sufficiently high number of areas in order to find a more common delineation of the Coral Triangle. Many corals are widespread and have a long fossil record. Moreover, coral reefs have not always been located in their present positions. This makes it complex to find which processes have caused a present diversity maximum. Since most species are concentrated in the eastern part of the Indo-Malayan archipelago and part of the West Pacific, this may be the area where most of the youngest species have originated, but sea-level fluctuations probably have been responsible for excluding large continental shelf seas from the Coral Triangle. [ABSTRACT FROM AUTHOR]

The influence of land barriers on the evolution of 50 species of pontoniine shrimps, living in association with molluscs and solitary ascidians, is studied. The interplay between the biological characteristics of the shrimps in the Atlantic/East Pacifi c area resulted in a biogeographical pattern best explained by a series of vicariance events. Distributional pattern in the Indo-West Pacifi c shows a centre of maximum diversity in eastern Indonesia, the Philippines, and New Guinea. This can be explained by the overlap of Asian, Pacifi c, and Australian distribuion ranges and/or the accumulation of inwardly directed, convergent dispersal, of peripheral originated species. [ABSTRACT FROM AUTHOR]

Megapodes (Megapodiidae), the most peculiar of all Galliformes, are of Gondwana origin. On the Australian plate they shifted from normal avian incubation to their aberrant strategy of incubating eggs in mounds of sand and leaf litter where heat is generated by microbial decomposition. From here, they spread through the Indonesian archipelago and eastwards into Polynesia, resulting in rapid speciation and the use of alternative heat sources for the incubation of their eggs. [ABSTRACT FROM AUTHOR]

The present knowledge of the historical biogeography of aquatic invertebrate groups is reviewed. Most orders of aquatic insects have a fossil record starting in the Early Permian, or Middle Carboniferous (Odonata), making even the break-up of Gondwana (Late Jurassic) relevant to understanding present distributional patterns. The complex geological history of Southeast Asia is summarized, and geological area cladograms presented. Biogeographical studies are seriously hampered by the limited information on subaerial history of the various islands and terranes. The historical biogeography of the Platycnemididae (Odonata), with special reference to the subfamily Calicnemiinae, is presented as one of the first examples of such a study of a widespread group. The species of southeast Asia derived from African Platycnemididae. Malesian Calicnemiinae derived from ancestors on the mainland of Asia, and may have dispersed along the Izu-Bonin Arc (40-50 Ma), or along the Late Cretaceous "Inner Melanesian Arc" sensus Polhemus. A clade of the genera Lieftinckia and Risiocnemis (Solomon Islands and the Philippines) represents a more recent westward dispersal of the Calicnemiinae, via the Caroline and Philippine Arcs during the Oligocene. Various other more limited phylogenetic reconstructions and biogeographical analyses of other freshwater invertebrates, particularly Odonata and Hemiptera, are discussed. Areas of endemism on New Guinea are generally congruent with geological entities recognized, e.g., the microterranes along the northern margin of New Guinea. Special attention is paid to the fauna of Sulawesi. Area cladistic reconstructions based on distribution patterns and phylogenetic reconstructions of, e.g., Protosticta Selys (Odonata, Platystictidae) and genera and species of Chlorocyphidae (Odonata), show a pattern of (northern arm (southwest arm - central and southeastern arm)), which is a reflection of the geological history of the island. Biogeographical patterns recognized in freshwater invertebrates of Malesia do not principally differ from those found in strictly terrestrial taxa. The distribution of land and water seems to be the driving force in speciation during the Cenozoicum. It is unresolved whether rafting of biotas on the various island arcs, or congruent patterns in dispersal, are to be considered the underlying principle. The extreme habitat requirements and poor dispersal power of many species involved seem to make a dispersal scenario unlikely. However, recent studies show that such habitat specialization may develop rapidly. [ABSTRACT FROM AUTHOR]

Total evidence scenarios for the origin of wide and disjunct distributions in two groups of flying insects, butterflies and parasitic wasps, are discussed, with emphasis on the possible role of the break-up of Gondwana. All six families of butterflies (Hesperiidae, Papilionidae, Pieridae, Lycaenidae, Riodinidae, and Nymphalidae) and two families of wasps (Stephanidae and Braconidae) have been examined for obvious disjunct distributions. The evidence for the impact of the fragmentation of Pangea and Gondwana on the global distribution of butterflies and both wasp families is considered to be weak. For the basal lineages of Braconidae, occupation of the niche of galls and "pseudogalls" (e.g., aphids) has been a more important driving force than vicariance. Obviously, dispersal and extinction played an important role before and after the break-up of the continents. They are integral parts of the evolution of life, ongoing processes, now and then punctuated by vicariance events, of which the traces will become obliterated with time. Dominance of vicariance events for the evolution of the families studied in this paper is considered unlikely. [ABSTRACT FROM AUTHOR]