Host specificity in the parasitic plant Cytinus hypocistis was quantified at four sites in the Algarve region of Portugal from 2002 to 2007. The parasite was found to be locally host specific, and only two hosts were consistently infected: Halimium halimifolium and Cistus monspeliensis. C. hypocistis did not infect hosts in proportion to their abundance; at three sites, 100% of parasites occurred on H. halimifolium which represented just 42.4%, 3% and 19.7% of potential hosts available, respectively. At the remaining site, where H. halimifolium was absent, 100% of parasites occurred on C. monspeliensis which represented 81.1% of potential hosts available. Other species of potential host were consistently uninfected irrespective of their abundance. Ecological niche divergence of host plants H. halimifolium and C. monspeliensis may isolate host-specific races of C. hypocistis, thereby potentially driving allopatric divergence in this parasitic plant.

C. J. Thorogood

S. J. Hiscock

Host Specificity in the Parasitic Plant Cytinus hypocistis

Aiming to provide a unified theory of ionic liquids ecotoxicity, the recent spectral structure activity relationship (S-SAR) algorithm is employed for testing the two additive models of anionic-cationic interaction containing ionic liquid activity: the causal and the endpoint, <mml:math id="E1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mrow><mml:mo>|</mml:mo><mml:mrow><mml:mn>0</mml:mn><mml:mo>+</mml:mo><mml:mo>〉</mml:mo></mml:mrow></mml:mrow></mml:mrow></mml:math> and <mml:math id="E2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mrow><mml:mo>|</mml:mo><mml:mrow><mml:mn>1</mml:mn><mml:mo>+</mml:mo><mml:mo>〉</mml:mo></mml:mrow></mml:mrow></mml:mrow></mml:math> models, respectively. As a working system, the Daphnia magna ecotoxicity was characterized through the formulated and applied spectral chemical-ecobiological interaction principles. Specific anionic-cationic-ionic-liquid rules of interaction along the developed mechanistic hypersurface map of the main ecotoxicity paths together with the so-called resonance limitation of the standard statistical correlation analysis were revealed.

Mihai V. Putz

Ana-Maria Lacrama

Vasile Ostafe

Spectral SAR Ecotoxicology of Ionic Liquids: The Daphnia magna Case

Unlike most terrestrial mammals, female bats must supply their offspring with all required nutrients until pups achieve virtually adult size, at which time they are able to fly and become independent. Access to nutrients may be especially challenging for reproductively active females in mineral-poor landscapes such as tropical rainforests. We hypothesized that pregnant and lactating females from tropical landscapes acquire essential nutrients from locally-available mineral licks. We captured ten times as many bats at mineral licks than at control sites in a lowland rainforest in eastern Ecuador. Among bats captured at mineral licks, the sex ratio was heavily biased toward females, and a significantly higher portion of females captured at these sites, compared to control sites, were reproductively active (pregnant and lactating). Enrichment of <mml:math id="E1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mtext>N</mml:mtext><mml:mrow><mml:mn>15</mml:mn></mml:mrow></mml:mrow></mml:math> in relation to <mml:math id="E2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mtext>N</mml:mtext><mml:mrow><mml:mn>14</mml:mn></mml:mrow></mml:mrow></mml:math> in wing tissue indicated that bats captured at mineral licks were mostly fruit-eating species. Given the high visitation rates of reproductive active females at mineral licks, it is likely that mineral licks are important for fruit-eating female bats as a mineral source during late pregnancy and lactation. By sustaining high population densities of fruit-eating bats that disperse seeds, mineral licks may have an indirect influence on local plant species richness.

Christian C. Voigt

Dina K. N. Dechmann

Jamie Bender

Benjamin J. Rinehart

Robert H. Michener

Thomas H. Kunz

Mineral Licks Attract Neotropical Seed-Dispersing Bats

The constancy of biomass density was considered in an entire plant population <mml:math id="E1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>p</mml:mi></mml:math> by combining two adjacent populations <mml:math id="E2" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>1</mml:mn></mml:msub></mml:mrow></mml:math> and <mml:math id="E3" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math> for which the self-thinning rule is assumed to be satisfied independently and each biomass density is also assumed to be the same constant value. Under these assumptions, the biomass density <mml:math id="E4" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>d</mml:mi></mml:math> in a population <mml:math id="E5" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>p</mml:mi></mml:math> was formulated as <mml:math id="E6" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>d</mml:mi><mml:mo>=</mml:mo><mml:mi>c</mml:mi><mml:mrow><mml:mrow><mml:mrow><mml:mo>(</mml:mo><mml:mo>(</mml:mo><mml:mrow><mml:mi>k</mml:mi><mml:msup><mml:mi>m</mml:mi><mml:mrow><mml:mo>−</mml:mo><mml:mi>α</mml:mi></mml:mrow></mml:msup><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow><mml:mo>)</mml:mo></mml:mrow><mml:mrow><mml:mo>(</mml:mo><mml:mrow><mml:mi>k</mml:mi><mml:mi>m</mml:mi><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow><mml:mo>)</mml:mo></mml:mrow></mml:mrow><mml:mo>/</mml:mo><mml:mrow><mml:mrow><mml:mo>(</mml:mo><mml:mrow><mml:mi>k</mml:mi><mml:msup><mml:mi>m</mml:mi><mml:mrow><mml:mn>1</mml:mn><mml:mo>−</mml:mo><mml:mi>α</mml:mi></mml:mrow></mml:msup><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow><mml:mo>)</mml:mo></mml:mrow></mml:mrow></mml:mrow><mml:mrow><mml:mo>(</mml:mo><mml:mrow><mml:mi>k</mml:mi><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow><mml:mo>)</mml:mo><mml:mo>)</mml:mo></mml:mrow></mml:mrow></mml:math>, where <mml:math id="E7" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>c</mml:mi></mml:math> is biomass density of <mml:math id="E8" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>1</mml:mn></mml:msub></mml:mrow></mml:math> and <mml:math id="E9" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>, and <mml:math id="E10" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>k</mml:mi></mml:math> and <mml:math id="E11" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>m</mml:mi></mml:math> are stand area and density ratio of <mml:math id="E12" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>1</mml:mn></mml:msub></mml:mrow></mml:math> to <mml:math id="E13" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>, respectively, and <mml:math id="E14" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>α</mml:mi></mml:math> is the self-thinning slope. In the case of <mml:math id="E15" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>m</mml:mi><mml:mo>≠</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:math>, the value of <mml:math id="E16" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>d</mml:mi></mml:math> in the above equation is always larger than unity. This fact indicates that the biomass density in a combined population <mml:math id="E17" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>p</mml:mi></mml:math> is not equal to the biomass density <mml:math id="E18" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>c</mml:mi></mml:math> in each population <mml:math id="E19" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>1</mml:mn></mml:msub></mml:mrow></mml:math> or <mml:math id="E20" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>p</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math> because of systematic error.

Kazuharu Ogawa

A Consideration of the Constancy of Biomass Density in Plant Populations Undergoing Self-Thinning

The role that plant-derived smoke plays in promoting seed germination is well documented, but little is known about its ability to inhibit seed germination. To better understand this phenomenon, we tested the effects of eight aerosol smoke treatments on the Columbia-3 ecotype of nondormant Arabidopsis thaliana (L.) Heynh. seeds. Our results revealed that aerosol smoke significantly inhibits germination when seeds were exposed to prolonged periods of aerosol smoke. Short durations of smoke treatments significantly promoted the rate of germination of A. thaliana seed. We briefly discuss this dual regulation of smoke and its possible impact on conservation and restoration practices. We also propose that plant-derived smoke may be another vehicle by which allelochemicals can be introduced into the environment.

Marcello Pennacchio

Lara V. Jefferson

Kayri Havens

Allelopathic Effects of Plant-Derived Aerosol Smoke on Seed Germination of Arabidopsis thaliana (L.) Heynh.

Cooperation, both intraspecific and interspecific, is a well-documented phenomenon in nature that is not well understood. Evolutionary game theory is a powerful tool to approach this problem. However, it has important limitations. First, very often it is not obvious which game is more appropriate to use. Second, in general, identical payoff matrices are assumed for all players, a situation that is highly unlikely in nature. Third, slight changes in these payoff values can dramatically alter
the outcomes. Here, I use an evolutionary spatial model in which players do not have a universal payoff matrix, so no payoff parameters are required. Instead, each is equipped with random values for the payoffs, fulfilling the constraints that define the game(s). These payoff matrices evolve by natural selection. Two versions of this model are studied. First is a simpler one, with just one evolving payoff. Second is the “full” version, with all the four payoffs evolving. The fraction of cooperator agents converges in both versions to nonzero values. In the case of the full version, the initial heterogeneity disappears and the selected game is the “Stag Hunt.”

H. Fort

Evolving Ecological Social Dilemmas: A Spatial Individual-Based Model for the
Evolution of Cooperation with a Minimal Number of Parameters

The Cope’s rule predicts a tendency for species to evolve towards an increase in size. Recently, it has been suggested that such a tendency is due to the fact that large body sizes provide a general increase in individual fitness. Here we highlight evidence that predator species do not always fit the large-size = high-fitness mechanism for Cope’s rule. Given the specific requirements of predators and the complexity of prey-predator relationships, any analysis that does not take into account all animal groups may overlook a significant portion of evolutive trends. Generalisations may not be possible regardless of taxa.

Vincenzo Penteriani

Robert Kenward

Does a Simple Cope's Rule Mechanism Overlook Predators?

The objective of this study was to determine whether endozoochory contributes to the dispersal and colonization of plant species in recently formed coastal dunes. At least 5.7% of species present in the study area are being dispersed by wild rabbits (Oryctolagus cuniculus L.). Most dispersed species are perennial herbs with small seeds size. The continuous input of seeds through rabbit feces into newly created areas would ensure the constant arrival of seeds and would facilitate colonization. Therefore, endozoochorous dispersal may play a relevant role for the structure and composition of dune plant communities.

C. M. Dellafiore

J. B. Gallego-Fernández

S. Muñoz Vallés

The Contribution of Endozoochory to the Colonization and Vegetation Composition of Recently Formed Sand Coastal Dunes

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International Journal of Ecology publishes articles in all areas of ecological sciences, The journal encourages the submission of big data studies, either presenting novel findings from large datasets or demonstrating new analytical techniques.

International Journal of Ecology