scholarly journals Camouflaged or tanned: plasticity in freshwater snail pigmentation

2013 ◽  
Vol 9 (5) ◽  
pp. 20130464 ◽  
Author(s):  
Johan Ahlgren ◽  
Xi Yang ◽  
Lars-Anders Hansson ◽  
Christer Brönmark
Keyword(s):  
Phenotypic Plasticity ◽  
Ultraviolet Radiation ◽  
Water Body ◽  
Freshwater Snail ◽  
Freshwater Snails ◽  
Plastic Response ◽  
Trade Off ◽  
Pattern Complexity ◽  
Radix Balthica ◽  
Dark Pigmentation

By having phenotypically plastic traits, many organisms optimize their fitness in response to fluctuating threats. Freshwater snails with translucent shells, e.g. snails from the Radix genus, differ considerably in their mantle pigmentation patterns, with snails from the same water body ranging from being completely dark pigmented to having only a few dark patterns. These pigmentation differences have previously been suggested to be genetically fixed, but we propose that this polymorphism is owing to phenotypic plasticity in response to a fluctuating environment. Hence, we here aimed to assess whether common stressors, including ultraviolet radiation (UVR) and predation, induce a plastic response in mantle pigmentation patterns of Radix balthica . We show, in contrast to previous studies, that snails are plastic in their expression of mantle pigmentation in response to changes in UVR and predator threats, i.e. differences among populations are not genetically fixed. When exposed to cues from visually hunting fish, R. balthica increased the proportion of their dark pigmentation, suggesting a crypsis strategy. Snails increased their pigmentation even further in response to UVR, but this also led to a reduction in pattern complexity. Furthermore, when exposed to UVR and fish simultaneously, snails responded in the same way as in the UVR treatment, suggesting a trade-off between photoprotection and crypsis.

scholarly journals Inbreeding depression in adaptive plasticity under predation risk in a freshwater snail

2009 ◽  
Vol 6 (2) ◽  
pp. 222-224 ◽  
Author(s):  
Josh R. Auld ◽  
Rick A. Relyea
Keyword(s):  
Phenotypic Plasticity ◽  
Predation Risk ◽  
Inbreeding Depression ◽  
Environmental Conditions ◽  
Chemical Cues ◽  
Natural Populations ◽  
Freshwater Snail ◽  
Adaptive Plasticity ◽  
Plastic Response ◽  
Physa Acuta

While much attention has been paid to the effects of inbreeding on fitness, this has mostly come from a genetic perspective. Consequently, the interaction between inbreeding and the environment is less well understood. To understand the effects of inbreeding in natural populations where environmental conditions are variable, we need to examine not only how the effects of inbreeding change among environments but also how inbreeding may affect the ability to respond to environmental conditions (i.e. phenotypic plasticity). We reared selfed and outcrossed hermaphroditic snails ( Physa acuta ) in the presence and absence of chemical cues from predatory crayfish and quantified expression of an inducible defence, an adaptively plastic response to predation risk. Overall, inbred snails exhibited reduced defences, but more importantly, inbreeding reduced the expression of predator-induced adaptive plasticity. Inbreeding depression in defensive morphology was 26 per cent and inbreeding depression in the plasticity of this trait was 48 per cent. Inbreeding depression in adaptive plasticity may be important to understanding the effects of inbreeding in nature.

Freshwater snail responses to fish predation integrate phenotypic plasticity and local adaptation

2020 ◽  
Vol 54 (1) ◽  
pp. 309-322 ◽  
Author(s):  
Scott R. Goeppner ◽  
Maggie E. Roberts ◽  
Lynne E. Beaty ◽  
Barney Luttbeg
Keyword(s):  
Phenotypic Plasticity ◽  
Local Adaptation ◽  
Fish Predation ◽  
Freshwater Snail

scholarly journals Competitive interactions between species of freshwater snails: I. Laboratory: Ia. General methodology

1983 ◽  
Vol 78 (3) ◽  
pp. 335-341 ◽  
Author(s):  
Frederico Simões Barbosa ◽  
Dirceu P. Pereira da Costa ◽  
Francisco Arruda
Keyword(s):  
Laboratory Experiments ◽  
Freshwater Snail ◽  
Current Paper ◽  
Competitive Interactions ◽  
Laboratory Work ◽  
Freshwater Snails ◽  
Technical Advance ◽  
General Methodology ◽  
Different Types ◽  
Set Up

For the development of laboratory experiments on the competitive interacitons between freshwater snail populations, special snail rooms were set up in the main building of the Research Center "Aggeu Magalhães". In the current paper, the first of a series on this subject, the general methodology of the laboratory work is described in detail. Using indoor cement channels in which a uniform seminatural environment was created, interactions of freshwater snail populations can be studied with minimal interference of the usual variables. Controlled indoor environmental techniques, as described in the current paper, may also be utilized in different types of experiments in malacology, and represent a substantial technical advance in malacological work.

scholarly journals Phenotypic plasticity and diversity in insects

2010 ◽  
Vol 365 (1540) ◽  
pp. 593-603 ◽  
Author(s):  
Armin P. Moczek
Keyword(s):  
Gene Expression ◽  
Phenotypic Plasticity ◽  
Natural Populations ◽  
Evolutionary Developmental Biology ◽  
Life Cycles ◽  
Biological Organization ◽  
Trade Off ◽  
Evolutionary Innovation ◽  
Trade Offs ◽  
Evolutionary Trajectories

Phenotypic plasticity in general and polyphenic development in particular are thought to play important roles in organismal diversification and evolutionary innovation. Focusing on the evolutionary developmental biology of insects, and specifically that of horned beetles, I explore the avenues by which phenotypic plasticity and polyphenic development have mediated the origins of novelty and diversity. Specifically, I argue that phenotypic plasticity generates novel targets for evolutionary processes to act on, as well as brings about trade-offs during development and evolution, thereby diversifying evolutionary trajectories available to natural populations. Lastly, I examine the notion that in those cases in which phenotypic plasticity is underlain by modularity in gene expression, it results in a fundamental trade-off between degree of plasticity and mutation accumulation. On one hand, this trade-off limits the extent of plasticity that can be accommodated by modularity of gene expression. On the other hand, it causes genes whose expression is specific to rare environments to accumulate greater variation within species, providing the opportunity for faster divergence and diversification between species, compared with genes expressed across environments. Phenotypic plasticity therefore contributes to organismal diversification on a variety of levels of biological organization, thereby facilitating the evolution of novel traits, new species and complex life cycles.

scholarly journals New molluscicides in control of freshwater snails – intermediate hosts for causative agents of fascioliasis, paramphistomatosis and orientobilharziasis

2020 ◽  
Author(s):  
N. E. Yuldashev ◽  
Keyword(s):  
Hydrogen Peroxide ◽  
Potassium Chloride ◽  
Ammonium Sulfate ◽  
Potassium Permanganate ◽  
Freshwater Snail ◽  
Mineral Fertilizers ◽  
Freshwater Snails ◽  
Table Salt ◽  
Intermediate Hosts ◽  
Causative Agents

The article presents the results of studying the new and affordable means for freshwater snail control. It was found that mineral fertilizers – ammonium sulfate at a concentration of 0.05–0.2%, and potassium chloride at a concentration of 0.2–0.3% cause the death of snails of the genera Lymnae and Planorbis in 24–72 hours after application. Hydrogen peroxide at a concentration of 1:40000 and potassium permanganate at a concentration of 1:400000 also kill snails within 24–48 hours. Commonly available products also have pronounced molluscicidal action: table salt (NaCl) and baking soda (NaHCO3) at concentrations of 0.3–0.5%. Changing the pH in the habitat of snails, i.e. waters in snail biotopes, towards acidity (3.8–6.2) and alkalinity (8.0–8.4) also result in the death of snails, and the optimal environment is with pH = 7.8. These means are safe for animals and the environment, as evidenced by the results of experiments carried out on sheep, which were administered with molluscicide solutions forcibly using a probe in an amount of 1.5 liters and by free drinking for 3 days.

scholarly journals Asexual freshwater snails make poor mate choice decisions

2021 ◽  
Author(s):  
Sydney Stork ◽  
Joseph Jalinsky ◽  
Maurine Neiman
Keyword(s):  
New Zealand ◽  
Mate Choice ◽  
Sexual Reproduction ◽  
Asexual Reproduction ◽  
Freshwater Snail ◽  
Freshwater Snails ◽  
Choice Assay ◽  
Mating Choice ◽  
Related Trait ◽  
Over Time

Once-useful traits that no longer contribute to fitness tend to decay over time. We address whether the expression of mating-related traits that increase the fitness of sexually reproducing individuals but are likely less useful or even costly to asexual counterparts seems to exhibit decay in the latter. Potamopyrgus antipodarum is a New Zealand freshwater snail characterized by repeated transitions from sexual to asexual reproduction. The frequent coexistence of sexual and asexual lineages makes P. antipodarum an excellent model for the study of mating-related trait loss. We used a mating choice assay including sexual and asexual P. antipodarum females and conspecific (presumed better choice) vs. heterospecific (presumed worse choice) males to evaluate the loss of behavioural traits related to sexual reproduction. We found that sexual females engaged in mating behaviours with conspecific mating partners more frequently and for a greater duration than with heterospecific mating partners, while asexual females seemed to lack the ability to make a choice. These results suggest that selection acting to maintain mate choice in asexual P. antipodarum is weak or ineffective relative to sexual females and that asexual reproduction likely contributes to the evolutionary decay of behavioural traits in this system.

scholarly journals LARVA TREMATODA PADA SIPUT AIR TAWAR DI AREAL PERSAWAHAN DAERAH ISTIMEWA YOGYAKARTA

2020 ◽  
Vol 19 (3B) ◽  
Author(s):  
Soenarwan Hery Poerwanto ◽  
Dian Antika Kusuma Dewi ◽  
Giyantolin Giyantolin
Keyword(s):  
Total Population ◽  
Freshwater Snail ◽  
Morphological Characters ◽  
Paddy Fields ◽  
Pomacea Canaliculata ◽  
Freshwater Snails ◽  
Larval Stages ◽  
Fresh Water Snail ◽  
Special Region ◽  
Yogyakarta City

The life cycle of Digenea subclass trematodes  that mostly involves snails as intermediate host in the larval stage in the form of sporocysts, redia and cercariae. This study aims to determine the species of freshwater snails, populations and stages of trematoda larvae that infect freshwater snails in the paddy fields and also the factors that influence the population of trematoda larvae. This research method uses purposive random sampling. Snails were collected from paddy fields in Sleman Regency, Yogyakarta City and Bantul Regency, Special Region of Yogyakarta. Snails and Trematodes larvae were identified based on morphological characters with a microscope. The results showed that the species of freshwater snail as  an inang antara  of Trematode was Lymnaea sp. (96.9%), Pomacea canaliculata (2.6%), and Brotia sp. (0.5%). The total population of trematoda larvae in freshwater snails was 4329 individuals with the largest population in Sleman Regency (2784 individuals). Trematode larval stages found were sporocysts (4.8%), redia (8.3%), Leptocercous type cercariae (35.2%), and Furcocercous type cercariae (51.7%). The most trematode larvae found in  fresh water snail was  Furcocercous type cercariae. Factor affecting trematode larvae population are the species and abundance of freshwater snail. 

scholarly journals Cercariae developing in Lymnaea natalensis Krauss, 1848 collected in the vicinity of Pretoria, Gauteng Province, South Africa

2008 ◽  
Vol 75 (3) ◽  
Author(s):  
E.B.E. Moema ◽  
P.H. King ◽  
C. Baker
Keyword(s):  
South Africa ◽  
Freshwater Snail ◽  
Freshwater Snails ◽  
Parasitic Diseases ◽  
Intermediate Hosts ◽  
Gauteng Province ◽  
The Family ◽  
Different Types ◽  
Lymnaea Natalensis ◽  
Scanning Electron

Freshwater snails are known to serve as first intermediate hosts for various parasitic diseases such as schistosomosis and fasciolosis. Snails were collected on several occasions in the proximity of Pretoria, South Africa and their cercarial sheddings were studied. This article describes three different types of cercariae shed by the freshwater snail, Lymnaea natalensis, viz. a fork-tailed cercaria of a Trichobilharzia sp., an avian parasite belonging to the family Schistosomatidae, an echinostomatid cercaria of the family Echinostomatidae, also avian parasites and a xiphidiocercaria of the family Plagiorchiidae which parasitise avians and amphibians. The morphology of these cercariae was studied by light and scanning electron microscopy.

scholarly journals Adaptive phenotypic plasticity in malaria parasites is not constrained by previous responses to environmental change

2019 ◽  
Vol 2019 (1) ◽  
pp. 190-198
Author(s):  
Philip L G Birget ◽  
Petra Schneider ◽  
Aidan J O’Donnell ◽  
Sarah E Reece
Keyword(s):  
Phenotypic Plasticity ◽  
Environmental Change ◽  
Life History Theory ◽  
Environmental Changes ◽  
Negative Consequences ◽  
Plastic Response ◽  
Malaria Parasites ◽  
Host Environment ◽  
Adaptive Phenotypic Plasticity ◽  
Plastic Responses

Abstract Background and objectives Phenotypic plasticity enables organisms to maximize fitness by matching trait values to different environments. Such adaptive phenotypic plasticity is exhibited by parasites, which experience frequent environmental changes during their life cycle, between individual hosts and also in within-host conditions experienced during infections. Life history theory predicts that the evolution of adaptive phenotypic plasticity is limited by costs and constraints, but tests of these concepts are scarce. Methodology Here, we induce phenotypic plasticity in malaria parasites to test whether mounting a plastic response to an environmental perturbation constrains subsequent plastic responses to further environmental change. Specifically, we perturb red blood cell resource availability to induce Plasmodium chabaudi to alter the trait values of several phenotypes underpinning within-host replication and between-host transmission. We then transfer parasites to unperturbed hosts to examine whether constraints govern the parasites’ ability to alter these phenotypes in response to their new in-host environment. Results Parasites alter trait values in response to the within-host environment they are exposed to. We do not detect negative consequences, for within-host replication or between-host transmission, of previously mounting a plastic response to a perturbed within-host environment. Conclusions and implications We suggest that malaria parasites are highly plastic and adapted to adjusting their phenotypes in response to the frequent changes in the within-host conditions they experience during infections. Our findings support the growing body of evidence that medical interventions, such as anti-parasite drugs, induce plastic responses that are adaptive and can facilitate the survival and potentially, drug resistance of parasites. Lay Summary Malaria parasites have evolved flexible strategies to cope with the changing conditions they experience during infections. We show that using such flexible strategies does not impact upon the parasites’ ability to grow (resulting in disease symptoms) or transmit (spreading the disease).

Freshwater snails of the genera Fluvidona and Austropyrgus (Gastropoda, Hydrobiidae) from northern New South Wales and southern Queensland, Australia

1999 ◽  
Vol 13 (3) ◽  
pp. 461 ◽  
Author(s):  
A. C. Miller ◽  
W. F. Ponder ◽  
S. A. Clark
Keyword(s):  
New Species ◽  
New South ◽  
New South Wales ◽  
Freshwater Snail ◽  
Freshwater Snails ◽  
South Eastern ◽  
South Wales ◽  
Small Streams ◽  
Eastern Australia ◽  
South Eastern Australia

The freshwater snail genus Fluvidona (Gastropoda, Caenogastropoda, Rissooidea, Hydrobiidae) is reapprasied and described using anatomical, shell, radula and opercular characters. Five species, three of them new, are described, being differentiated using anatomical, shell and opercular character states. A sixth species, similar to the Fluvidona species, is described and is tentatively assigned to the genus Austropyrgus Cotton. All six species live in northern New South Wales and southern Queensland and all are from single localities or very restricted areas. All species live in small streams, although one was found aestivating in soil in the bed of a small dry creek. The new species placed in Austropyrgus, from the Bunya Mountains, Queensland, is widely separated from putative congeners that are found in southern New South Wales and other parts of south-eastern Australia.

Sign in / Sign up

Export Citation Format

Share Document