scholarly journals Beetle Species–Area Relationships and Extinction Rates in Protected Areas

Insects ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 646
Author(s):  
Simone Fattorini
Keyword(s):  
Species Richness ◽  
Feeding Habits ◽  
Negative Influence ◽  
Extinction Rates ◽  
Ecological Patterns ◽  
Species Area ◽  
Local Extinctions ◽  
Species Area Relationship ◽  
Aquatic Predators ◽  
Using Data

The species–area relationship (SAR, i.e., the increase in species richness with area) is one of the most general ecological patterns. SARs can be used to calculate expected extinction rates following area (habitat) loss. Here, using data from Italian reserves, extinction rates were calculated for beetle groups with different feeding habits: Carabidae (terrestrial predators), Hydradephaga (aquatic predators), coprophagous Scarabaeoidea (dung feeders), phytophagous Scarabaeoidea (herbivores), and Tenebrionidae (detritivores). The importance of other factors besides area (namely latitude and elevation) was investigated. Reserve area was recovered as an important predictor of species richness in all cases. For Carabidae, Hydradephaga, and Tenebrionidae, elevation exerted a negative influence, whereas latitude had a negative influence on coprophagous Scarabaeoidea and Tenebrionidae, as a consequence of current and historical biogeographical factors. Extinction rates were higher for dung beetles, due to their dependence on large grazing areas, and Tenebrionidae, due to their low dispersal capabilities. The lower extinction rates predicted for Carabidae, phytophagous Scarabaeoidea, and Hydradephaga can be explained by their higher dispersal power. If other variables besides area are considered, extinction rates became more similar among groups. Extinction rates by area loss are always relatively low. Thus, in reserves with few species, many local extinctions might be unnoticed.

scholarly journals Conservation Biogeography of Tenebrionid Beetles: Insights from Italian Reserves

Diversity ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 348 ◽  
Author(s):  
Simone Fattorini
Keyword(s):  
Species Richness ◽  
Latitudinal Gradient ◽  
Important Determinant ◽  
Elevational Gradient ◽  
Negative Influence ◽  
Species Dispersal ◽  
Conservation Biogeography ◽  
Extinction Rates ◽  
Species Area ◽  
Using Data

The species-area relationship (SAR), the latitudinal gradient, the peninsula effect, and the elevational gradient are widespread biogeographical patterns. Using data from Italian reserves, these patterns were tested for tenebrionids and used as a framework to calculate expected extinction rates following area loss. Area was an important determinant of overall tenebrionid species richness, but not for xylophilous and endemic species. Thus, focusing on reserve areas is not the best approach for conserving insects with specialised ecology and restricted distribution. In general, species richness declined northwards, which contrasts with the peninsula effect, but conforms to the European latitudinal pattern observed in most taxa because of current and past biogeographical factors. Minimum elevation had an overall negative influence, as most tenebrionids are thermophilic. However, xylophilous tenebrionids, which are mainly associated with mesophilic forests, did not decline northwards, and were positively influenced by higher elevational ranges that allow more forms of vegetation. SAR-based extinction rates reflect species dispersal capabilities, being highest for geophilous species (which are mainly flightless), and lower for the xylophilous species. Extinction rates based on multiple models indicate that the use of area alone may overestimate extinction rates, when other factors exert an important role in determining species richness.

Hot-Spot Facts and Artifacts-Questioning Israel's Great Biodiversity

2009 ◽  
Vol 55 (3) ◽  
pp. 263-279 ◽  
Author(s):  
Uri Roll ◽  
Lewi Stone ◽  
Shai Meiri
Keyword(s):  
Species Richness ◽  
Biological Diversity ◽  
Hot Spot ◽  
Flowering Plants ◽  
Prediction Intervals ◽  
Predicting Factors ◽  
Mediterranean Countries ◽  
Species Area ◽  
Expected Values ◽  
Species Area Relationship

Israel's biological diversity has been praised as being particularly rich in relation to its size; however this assumption was never tested when taking into account the empirical form of the species-area relationship. Here we compared the species richness of different countries to see if the Israeli diversity is exceptionally rich when area is accurately accounted for. We compared richness of amphibians, birds, mammals, reptiles, flowering plants, conifers and cycads, and ferns in all the world's countries. We further tested the effects of mean latitude, altitude span, and insularity on species richness both for all world countries and just for Mediterranean countries. For all taxa and in all tests, Israel lies within the prediction intervals of the models. Out of 42 tests, Israel's residuals lie in the upper decile of positive residuals once: for reptiles, when compared to all world countries, taking all predicting factors into account. Using only countries larger than 1000 km2, Israel was placed as top residual when compared to other Mediterranean countries for mammals and reptiles. We therefore conclude that Israel's species richness does not significantly exceed the expected values for a country its size. This is true when comparing it to either world or just Mediterranean countries. Adding more predicting factors does not change this fact.

Organisation de la richesse et de la composition floristiques d'îles de la Méditerranée occidentale (sud-est de la France)

1998 ◽  
Vol 76 (2) ◽  
pp. 321-331 ◽  
Author(s):  
Frédéric Médail ◽  
Éric Vidal
Keyword(s):  
Species Richness ◽  
Species Composition ◽  
Plant Species ◽  
Habitat Diversity ◽  
Mediterranean Islands ◽  
Plant Dispersal ◽  
Number Of Species ◽  
Continental Islands ◽  
Species Area ◽  
Species Area Relationship

The effects of physiographic variables (area, isolation, elevation, and substrate) and habitat diversity on plant species richness and composition have been investigated on some Mediterranean islands (southeastern France). The number of species - area relationship is significant but there are more diverse vegetation patterns on smallest islands (area smaller than 3.5 ha and, ultimately, 0.2 ha). Although the species composition is positively correlated to the distance from the continent, the effect of isolation is not so obvious because of the small distance of these continental islands from the continent. Some islands nearest to shore show very different plant species composition, suggesting a nonselective plant dispersal through some narrow stretches of sea. Habitat diversity represents one of the major explanatory factors of the species richness; nevertheless, it is not possible to settle between the two hypotheses effect of habitat diversity versus effect of area per se because of the correlation between the two factors. Key words: Mediterranean islands, insular biogeography, number of species - area relationship, isolation, habitat diversity, islets.

scholarly journals Wood ant assemblages of Formica rufa group on lake islands and in mainland woodland in Central Finland

2018 ◽  
Vol 29 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Jouni Sorvari
Keyword(s):  
Species Richness ◽  
Occurrence Probability ◽  
Island Size ◽  
Formica Rufa ◽  
Wood Ants ◽  
Formica Rufa Group ◽  
Species Area ◽  
Island Community ◽  
Species Area Relationship ◽  
Formica Lugubris

Associations of island size and isolation on the occurrence and species richness of five wood ant species of the Formica rufa group (F. rufa, F. aquilonia, F. lugubris, F. polyctena and F. pratensis) was tested in the Lake Konnevesi archipelago in Central Finland. In addition, the species composition was compared to that of mainland forests of the same region. Island isolation had no associations with the wood ant occurrence in this archipelago, but for most species, increasing island size was positively associated with the occurrence probability. According to the findings among the five species, Formica lugubris is the best adapted for insular living. There was a positive species–area relationship as the species richness of wood ants increased with an increasing island size. The island community of wood ants was dominated by colonies of the monogynous (single queen) species whereas the mainland community was dominated by those of polygynous (multiple queen) species.

scholarly journals The mathematics of extinction across scales: from populations to the biosphere

2017 ◽  
Author(s):  
Colin Carlson ◽  
Kevin Burgio ◽  
Tad Dallas ◽  
Wayne Getz
Keyword(s):  
Extinction Risk ◽  
Population Viability Analysis ◽  
Population Viability ◽  
Occupancy Models ◽  
Viability Analysis ◽  
Extinction Rates ◽  
Sixth Mass Extinction ◽  
Evolutionary Rescue ◽  
Species Area ◽  
Using Data

The sixth mass extinction poses an unparalleled quantitative challenge to conservation biologists. Mathematicians and ecologists alike face the problem of developing models that can scale predictions of extinction rates from populations to the level of a species, or even to an entire ecosystem. We review some of the most basic stochastic and analytical methods of calculating extinction risk at different scales, including population viability analysis, stochastic metapopulation occupancy models, and the species area relationship. We also consider two major extensions of theory: the possibility of evolutionary rescue from extinction in a changing environment, and the posthumous assignment of an extinction date from sighting records. In the case of the latter, we provide a new example using data on Spix's macaw (Cyanopsitta spixii), the "rarest bird in the world," to demonstrate the challenges associated with extinction date research.

scholarly journals Correlation/causation in ecology: towards mechanistic explanations for the Species-Area Relationship

2016 ◽  
Author(s):  
Andersonn Prestes
Keyword(s):  
Species Richness ◽  
Positive Relationship ◽  
Abiotic Factors ◽  
Causal Explanations ◽  
Biotic And Abiotic Factors ◽  
Mechanistic Explanations ◽  
Species Area ◽  
Species Area Relationship ◽  
Per Se ◽  
Recurrent Patterns

There is a common intuition in biology that strict laws are very difficult to be found. Still, there are recurrent patterns in nature, suggesting broad generalizations and understanding of phenomena. The problem is that many generalizations in biology, especially in the form of correlations, might be decoupled from causality, weakening their power of explanation. Here, I bring an example on the Species-Area Relationship (SAR). The SAR is a well-known generalization in biology. The recurrent pattern states a positive relationship between area size and species richness. Understanding the mechanisms why there is a correlation between area and diversity remains a major challenge. I suggest an explicitly focus on mechanistic explanations for the SAR. I propose to use the integration, comparison and interpretation of other (associated or secondary) natural patterns in the searching for causal explanations. Area per se might not account for causality in species diversification or absolute species richness in larger regions. Biotic and abiotic factors of a given area might be studied in order to discover the causal underpinnings of the SAR.

Species and Generic Gamma-Scale Diversity in Shallow-Water Marine Amphipoda with Particular Reference to the Mediterranean

1996 ◽  
Vol 76 (1) ◽  
pp. 195-202 ◽  
Author(s):  
A.A. Myers
Keyword(s):  
Species Richness ◽  
Mediterranean Sea ◽  
Late Miocene ◽  
Evolutionary History ◽  
Amphipod Species ◽  
Species Area ◽  
Species Area Relationship ◽  
The Mediterranean ◽  
Shallow Seas

Major hotspots of amphipod species richness and of species and generic endemicity can be recognized in shallow seas. Recognition of ‘hotspots’ for amphipods must take account of the species-area relationship but not of latitude. The richness and endemicity of amphipods in the Mediterranean Sea is shown to be high when compared with other shallow seas This indicates a long in situ evolutionary history and is therefore not compatible with the hypothesis that the Mediterranean fauna was extirpated in the late Miocene.

scholarly journals The mathematics of extinction across scales: from populations to the biosphere

2018 ◽  
Author(s):  
Colin Carlson ◽  
Kevin Burgio ◽  
Tad Dallas ◽  
Wayne Getz
Keyword(s):  
Extinction Risk ◽  
Population Viability Analysis ◽  
Population Viability ◽  
Occupancy Models ◽  
Viability Analysis ◽  
Extinction Rates ◽  
Sixth Mass Extinction ◽  
Evolutionary Rescue ◽  
Species Area ◽  
Using Data

The sixth mass extinction poses an unparalleled quantitative challenge to conservation biologists. Mathematicians and ecologists alike face the problem of developing models that can scale predictions of extinction rates from populations to the level of a species, or even to an entire ecosystem. We review some of the most basic stochastic and analytical methods of calculating extinction risk at different scales, including population viability analysis, stochastic metapopulation occupancy models, and the species area relationship. We also consider two major extensions of theory: the possibility of evolutionary rescue from extinction in a changing environment, and the posthumous assignment of an extinction date from sighting records. In the case of the latter, we provide an example using data on Spix's macaw (Cyanopsitta spixii), the "rarest bird in the world," to demonstrate the challenges associated with extinction date research.

Boreal ground-beetle (Coleoptera: Carabidae) assemblages of the mainland and islands in Lac la Ronge, Saskatchewan, Canada

2017 ◽  
Vol 149 (4) ◽  
pp. 491-503 ◽  
Author(s):  
Aaron J. Bell ◽  
Iain D. Phillips ◽  
Scott E. Nielsen ◽  
John R. Spence
Keyword(s):  
Species Richness ◽  
Island Biogeography ◽  
Passive Sampling ◽  
Unit Area ◽  
Ground Beetle ◽  
Small Islands ◽  
Island Size ◽  
Extinction Rates ◽  
Theory Of Island Biogeography ◽  
Species Area

AbstractWe tested the applicability of the “passive sampling” hypothesis and theory of island biogeography (TIB) for explaining the diversity of forest-dwelling carabid assemblages (Carabidae: Coleoptera) on 30 forested islands (0.2–980.7 ha) in Lac la Ronge and the adjacent mainland in Saskatchewan, Canada. Species richness per unit area increased with distance to mainland with diversity being highest on the most isolated islands. We detected neither a positive species-area relationship, nor significant differences in species richness among island size classes, or between islands and the mainland. Nonetheless, carabid assemblages distinctly differed on islands <1 ha in area and gradually approached the structure of mainland assemblages as island area increased. Small islands were characterised by abundant populations of small-bodied, winged species and few if any large-bodied, flightless species like Carabus taedatus Fabricius. Our findings suggest that neither the “passive sampling” hypothesis nor the theory of island biogeography adequately explain carabid beetle diversity patterns observed among islands in Lac la Ronge. Instead, we hypothesise that population processes such as higher extinction rates of large-bodied, flightless species and the associated release of smaller-bodied, flying species from intra-guild predation on small islands contribute to observed differences in the structure of carabid assemblages between islands.

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