Total Non-Consumptive Effects of Fish on Pelobates fuscus and Hyla orientalis Tadpoles in Pond Enclosure Experiments

Butterflies are among nature's most colourful animals, and provide a living showcase for how extremely bright, chromatic and iridescent coloration can be generated by complex optical mechanisms. The gross characteristics of male butterfly colour patterns are understood to function for species and/or sex recognition, but it is not known whether female mate choice promotes visual exaggeration of this coloration. Here I show that females of the sexually dichromatic species Hypolimnas bolina prefer conspecific males that possess bright iridescent blue/ultraviolet dorsal ornamentation. In separate field and enclosure experiments, using both dramatic and graded wing colour manipulations, I demonstrate that a moderate qualitative reduction in signal brightness and chromaticity has the same consequences as removing the signal entirely. These findings validate a long-held hypothesis, and argue for the importance of intra- versus interspecific selection as the driving force behind the exaggeration of bright, iridescent butterfly colour patterns.

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A decharming metamorphosis: The larval and adult morphology of the common spadefoot toad, Pelobates fuscus

Zoologischer Anzeiger ◽

10.1016/j.jcz.2021.11.005 ◽

2021 ◽

Author(s):

Kenny Jandausch ◽

Daniel Schwarz ◽

Bernhard Leopold Bock ◽

Paul Lukas

Keyword(s):

Adult Morphology ◽

Spadefoot Toad ◽

Pelobates Fuscus ◽

The Common

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Control of phosphorus and plankton by calcite flushing in Lake Arendsee: enclosure experiments

SIL Proceedings 1922-2010 ◽

10.1080/03680770.1995.11900820 ◽

1997 ◽

Vol 26 (2) ◽

pp. 768-771

Author(s):

Helmut Rönicke ◽

Helmut Klapper ◽

Jörg Tittel ◽

Michael Beyer ◽

Barbara Zippel

Keyword(s):

Enclosure Experiments

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Plankton Food Web Responses to Experimental Nutrient Additions in a Subtropical Lake

The Scientific World JOURNAL ◽

10.1100/tsw.2006.176 ◽

2006 ◽

Vol 6 ◽

pp. 827-833 ◽

Cited By ~ 3

Author(s):

Karl E. Havens ◽

Therese L. East

Keyword(s):

Food Web ◽

Microbial Food Web ◽

Cylindrospermopsis Raciborskii ◽

Variable Response ◽

Nitrogen And Phosphorus ◽

Subtropical Lake ◽

Nutrient Additions ◽

Cyanobacteria Blooms ◽

Enclosure Experiments

During two controlled enclosure experiments using water from a subtropical lake, the plankton food web displayed a highly variable response to combined addition of nitrogen and phosphorus. In July, the nutrients stimulated growth ofCylindrospermopsis raciborskii, and the biomass of macrozooplankton and microbial food web components did not increase. In October, the same addition of nutrients stimulated growth of small edibleLyngbyaspp., and there were coincident increases in biomass of macrozooplankton and components of the microbial web. Past generalizations that cyanobacteria blooms inhibit growth of other food web components may not always hold true.

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Algal Competition for Phosphorus: The Influence of Zooplankton and Fish

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f86-141 ◽

1986 ◽

Vol 43 (6) ◽

pp. 1135-1141 ◽

Cited By ~ 44

Author(s):

Helge Reinertsen ◽

Arne Jensen ◽

Arnfinn Langeland ◽

Yngvar Olsen

Keyword(s):

Interspecific Competition ◽

Green Alga ◽

Inorganic Carbon ◽

Blue Green Alga ◽

Physical Conditions ◽

Herbivorous Zooplankton ◽

Enclosure Experiments ◽

Algal Competition

Interspecific competition for phosphorus between the blue-green alga Anabaena flos-aquae and the green alga Staurastrum luetkemuelleri was studied in enclosure experiments. Both algal populations increased in number upon introduction of fish, but addition of herbivorous zooplankton led to an increase solely in the Staurastrum population. This could not be attributed to grazing by zooplankton, chemical or physical conditions (light, pH, inorganic carbon), or the total supply or rate of supply of phosphorus. The observed differences were apparently due to the patchy release of phosphorus by the fish, and the more homogenous release of this nutrient by the zooplankton. This would allow the Anabaena species, which was capable of rapid uptake of temporary pulses of phosphate, to coexist with Staurastrum in the enclosures with fish.

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