The Experts below are selected from a list of 1914 Experts worldwide ranked by ideXlab platform
Ralph Tollrian - One of the best experts on this subject based on the ideXlab platform.
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zooplankters nightmare the fast and efficient catching basket of larval phantom midges diptera Chaoborus
PLOS ONE, 2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Filter feeding zooplankton are a crucial component of limnic food webs. Copepods and cladocerans are important prey organisms for first-level predators like the common and abundant larvae of phantom midges (Chaoborus sp.). The latter possess a complex catching basket built of head appendages specialized to capture small crustaceans. The predator-prey-relationship of Chaoborus (Diptera, Nematocera) and Daphnia (Crustacea, Cladocera) has been studied in particular detail owing to the daphniids’ ability to react upon the threat of predation with inducible defenses. Daphnia pulex expresses so-called ‘neckteeth’ in the presence of Chaoborus larvae that are discussed as a defensive trait that interferes with the larval head appendages and their effectiveness has been shown in several studies. Nonetheless, mode of function of these neckteeth is not understood and the hypothesis that they interfere with the predator’s head appendages still has to be confirmed. To clarify the role of neckteeth in Daphnia, an understanding of the Chaoborus capture apparatus is essential. Here, we present a detailed three-dimensional analysis of Chaoborus obscuripes’ larval head morphology as well as a kinematic analysis of the attack motion, which revealed an impressive strike velocity (14 ms to prey contact). The movement of the larvae’s head appendages is reconstructed in the three-dimensional space using a combination of high-speed videography, micro-computed tomography and computer animation. Furthermore, we provide predation trial data to distinguish between pre- and post-attack defensive effects in D. pulex. Our findings suggest a combination of pre- and post-attack defenses with an average effectiveness of 50% each. With this study, we quantitatively describe prey capture kinematics of C. obscuripes and take a further step to reveal the neckteeth’ mode of function in D. pulex.
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 7
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Chaoborus obscuripes catching efficiency (n = 11, t-test, level of significances: p
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 6
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Surface model of the Chaoborus obscuripes larval head capsule with closed (left) and opened (right) catching basket. Scale bar = 500 μm.
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effects of vertebrate and invertebrate predators on the life history of daphnia similis and moina macrocopa crustacea cladocera
Annales De Limnologie-international Journal of Limnology, 2018Co-Authors: Jayme M Santangelo, Ralph Tollrian, Bruno Nascimento Soares, Thecia Alfenas Paes, Paulina Maiabarbosa, Reinaldo Luiz BozelliAbstract:Cladocerans serve as prey for several aquatic predators like fish and Chaoborus larvae. However, because different predators consume different sized prey, cladocerans may display differing life-history responses depending on predator type. Although most studies use the genus Daphnia to evaluate phenotypic plasticity in cladocerans, other genera might also respond to predator infochemicals. In this study, we compared life-history responses of Daphnia similis and Moina macrocopa to infochemicals released by a vertebrate (fish) and an invertebrate (Chaoborus ) predator. As expected, some life-history parameters were altered depending on the type of predator. Overall, fish infochemicals increased the size at primipara, clutch size, net reproductive rate and longevity in both cladocerans. We argue that increased body lengths in the presence of fish promote bigger clutch sizes. Conversely, responses to Chaoborus were weaker, affecting only the net reproductive rates and longevity. Non-daphniid cladocerans may display similar responses to Daphnia when exposed to predators. However, as Daphnia is usually underrepresented in tropical lakes, studying other genera might offer new insights into predator-prey relationships and food webs in lake ecosystems.
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Effects of vertebrate and invertebrate predators on the life history of
'EDP Sciences', 2018Co-Authors: Jayme M Santangelo, Ralph Tollrian, Bruno Nascimento Soares, Thecia Paes, Paulina Maia-barbosa, Reinaldo Luiz BozelliAbstract:Cladocerans serve as prey for several aquatic predators like fish and Chaoborus larvae. However, because different predators consume different sized prey, cladocerans may display differing life-history responses depending on predator type. Although most studies use the genus Daphnia to evaluate phenotypic plasticity in cladocerans, other genera might also respond to predator infochemicals. In this study, we compared life-history responses of Daphnia similis and Moina macrocopa to infochemicals released by a vertebrate (fish) and an invertebrate (Chaoborus) predator. As expected, some life-history parameters were altered depending on the type of predator. Overall, fish infochemicals increased the size at primipara, clutch size, net reproductive rate and longevity in both cladocerans. We argue that increased body lengths in the presence of fish promote bigger clutch sizes. Conversely, responses to Chaoborus were weaker, affecting only the net reproductive rates and longevity. Non-daphniid cladocerans may display similar responses to Daphnia when exposed to predators. However, as Daphnia is usually underrepresented in tropical lakes, studying other genera might offer new insights into predator-prey relationships and food webs in lake ecosystems.Although most studies use the genus Daphnia to evaluate phenotypic plasticity in cladocerans, other genera might also respond to predator infochemicals. In this study fish infochemicals increased the size at primipara, clutch size, net reproductive rate and longevity in Daphnia and Moina. Conversely, Chaoborus infochemicals affected only the net reproductive rates and longevity of cladocerans. Non-daphniid cladocerans may display similar responses to Daphnia when exposed to predators. However, as Daphnia is usually underrepresented in tropical lakes, studying other genera might offer new insights into predator-prey relationships and food webs in lake ecosystems
Linda C Weiss - One of the best experts on this subject based on the ideXlab platform.
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zooplankters nightmare the fast and efficient catching basket of larval phantom midges diptera Chaoborus
PLOS ONE, 2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Filter feeding zooplankton are a crucial component of limnic food webs. Copepods and cladocerans are important prey organisms for first-level predators like the common and abundant larvae of phantom midges (Chaoborus sp.). The latter possess a complex catching basket built of head appendages specialized to capture small crustaceans. The predator-prey-relationship of Chaoborus (Diptera, Nematocera) and Daphnia (Crustacea, Cladocera) has been studied in particular detail owing to the daphniids’ ability to react upon the threat of predation with inducible defenses. Daphnia pulex expresses so-called ‘neckteeth’ in the presence of Chaoborus larvae that are discussed as a defensive trait that interferes with the larval head appendages and their effectiveness has been shown in several studies. Nonetheless, mode of function of these neckteeth is not understood and the hypothesis that they interfere with the predator’s head appendages still has to be confirmed. To clarify the role of neckteeth in Daphnia, an understanding of the Chaoborus capture apparatus is essential. Here, we present a detailed three-dimensional analysis of Chaoborus obscuripes’ larval head morphology as well as a kinematic analysis of the attack motion, which revealed an impressive strike velocity (14 ms to prey contact). The movement of the larvae’s head appendages is reconstructed in the three-dimensional space using a combination of high-speed videography, micro-computed tomography and computer animation. Furthermore, we provide predation trial data to distinguish between pre- and post-attack defensive effects in D. pulex. Our findings suggest a combination of pre- and post-attack defenses with an average effectiveness of 50% each. With this study, we quantitatively describe prey capture kinematics of C. obscuripes and take a further step to reveal the neckteeth’ mode of function in D. pulex.
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 7
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Chaoborus obscuripes catching efficiency (n = 11, t-test, level of significances: p
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 6
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Surface model of the Chaoborus obscuripes larval head capsule with closed (left) and opened (right) catching basket. Scale bar = 500 μm.
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Identification of Chaoborus kairomone chemicals that induce defences in Daphnia
Nature Chemical Biology, 2018Co-Authors: Linda C Weiss, Sina M. Becker, Sven W. Meckelmann, Bauke Albada, Ulf Sommer, Martin Meyer, Julia Klein, Oliver J. Schmitz, Johannes ZagermannAbstract:Infochemicals play important roles in aquatic ecosystems. They even modify food web interactions, such as by inducing defenses in prey. In one classic but still not fully understood example, the planktonic freshwater crustacean Daphnia pulex forms specific morphological defenses (neckteeth) induced by chemical cues (kairomones) released from its predator, the phantom midge larva Chaoborus. On the basis of liquid chromatography, mass spectrometry, and chemical synthesis, we report here the chemical identity of the Chaoborus kairomone. The biologically active cues consist of fatty acids conjugated to the amino group of glutamine via the N terminus. These cues are involved in Chaoborus digestive processes, which explains why they are consistently released despite the disadvantage for its emitter. The identification of the kairomone may allow in-depth studies on multiple aspects of this inducible defense system.
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Chaoborus and gasterosteus anti predator responses in daphnia pulex are mediated by independent cholinergic and gabaergic neuronal signals
PLOS ONE, 2012Co-Authors: Linda C Weiss, Sebastian Kruppert, Christian Laforsch, Ralph TollrianAbstract:Many prey species evolved inducible defense strategies that protect effectively against predation threats. Especially the crustacean Daphnia emerged as a model system for studying the ecology and evolution of inducible defenses. Daphnia pulex e.g. shows different phenotypic adaptations against vertebrate and invertebrate predators. In response to the invertebrate phantom midge larvae Chaoborus (Diptera) D. pulex develops defensive morphological defenses (neckteeth). Cues originating from predatory fish result in life history changes in which resources are allocated from somatic growth to reproduction. While there are hints that responses against Chaoborus cues are transmitted involving cholinergic neuronal pathways, nothing is known about the neurophysiology underlying the transmission of fish related cues. We investigated the neurophysiological basis underlying the activation of inducible defenses in D. pulex using induction assays with the invertebrate predator Chaoborus and the three-spined stickleback Gasterosteus aculeatus. Predator-specific cues were combined with neuro-effective substances that stimulated or inhibited the cholinergic and gabaergic nervous system. We show that cholinergic-dependent pathways are involved in the perception and transmission of Chaoborus cues, while GABA was not involved. Thus, the cholinergic nervous system independently mediates the development of morphological defenses in response to Chaoborus cues. In contrast, only the inhibitory effect of GABA significantly influence fish-induced life history changes, while the application of cholinergic stimulants had no effect in combination with fish related cues. Our results show that cholinergic stimulation mediates signal transmission of Chaoborus cues leading to morphological defenses. Fish cues, which are responsible for predator-specific life history adaptations involve gabaergic control. Our study shows that both pathways are independent and thus potentially allow for adjustment of responses to variable predation regimes.
Sebastian Kruppert - One of the best experts on this subject based on the ideXlab platform.
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zooplankters nightmare the fast and efficient catching basket of larval phantom midges diptera Chaoborus
PLOS ONE, 2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Filter feeding zooplankton are a crucial component of limnic food webs. Copepods and cladocerans are important prey organisms for first-level predators like the common and abundant larvae of phantom midges (Chaoborus sp.). The latter possess a complex catching basket built of head appendages specialized to capture small crustaceans. The predator-prey-relationship of Chaoborus (Diptera, Nematocera) and Daphnia (Crustacea, Cladocera) has been studied in particular detail owing to the daphniids’ ability to react upon the threat of predation with inducible defenses. Daphnia pulex expresses so-called ‘neckteeth’ in the presence of Chaoborus larvae that are discussed as a defensive trait that interferes with the larval head appendages and their effectiveness has been shown in several studies. Nonetheless, mode of function of these neckteeth is not understood and the hypothesis that they interfere with the predator’s head appendages still has to be confirmed. To clarify the role of neckteeth in Daphnia, an understanding of the Chaoborus capture apparatus is essential. Here, we present a detailed three-dimensional analysis of Chaoborus obscuripes’ larval head morphology as well as a kinematic analysis of the attack motion, which revealed an impressive strike velocity (14 ms to prey contact). The movement of the larvae’s head appendages is reconstructed in the three-dimensional space using a combination of high-speed videography, micro-computed tomography and computer animation. Furthermore, we provide predation trial data to distinguish between pre- and post-attack defensive effects in D. pulex. Our findings suggest a combination of pre- and post-attack defenses with an average effectiveness of 50% each. With this study, we quantitatively describe prey capture kinematics of C. obscuripes and take a further step to reveal the neckteeth’ mode of function in D. pulex.
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 7
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Chaoborus obscuripes catching efficiency (n = 11, t-test, level of significances: p
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 6
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Surface model of the Chaoborus obscuripes larval head capsule with closed (left) and opened (right) catching basket. Scale bar = 500 μm.
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Chaoborus_larva_head_Reconstruction
2018Co-Authors: Sebastian Kruppert, Thomas Kleinteich, Stanislav N. GorbAbstract:Reconstruction (image stack) of a larval head of Chaoborus obscuripes (4th instar) based on micro-CT data. Specimen was chemically dried using an ascending alcohol series followed by aceton and hexamethyldisilazane according to Laforsch and Tollrian 2000.
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High-speed-video_footage_Chaoborus_larva_attacking_Dpulex
2018Co-Authors: Sebastian Kruppert, Lisa Deussen, Jonas O Wolff, Stanislav N. GorbAbstract:48 videos of Chaoborus larva attacks on Daphnia pulex in the second juvenile instar in either defended (ind) or undefended (ctrl) morph
Ricardo Motta Pintocoelho - One of the best experts on this subject based on the ideXlab platform.
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hydroacoustic assessment of fish and Chaoborus diptera chaoboridae distribution in three neotropical lakes
Acta Limnologica Brasiliensia, 2012Co-Authors: Jose Fernandes Bezerraneto, Ludmila Silva Brighenti, Nelson Azevedo Santos Teixeira De Mello, Ricardo Motta PintocoelhoAbstract:AIM: This study aims to demonstrate the potential of hydroacoustics in the study of behavior of the invertebrate Chaoborus and fish in neotropical water environments; METHODS: Synoptic campaigns were conducted in May and June-2008 in Dom Helvecio and Carioca lakes, at the Parque Estadual do Rio Doce (MG), and Nado reservoir, Belo Horizonte (MG). The acoustic scattering of targets was studied using a downward-oriented split-beam 200 kHz echosounder; RESULTS: We detected clear echo signals from fish and Chaoborus larvae, which can be viewed in high density in all environments studied. The normal migratory behavior of the larvae of Chaoborus could be easily monitored in the Dom Helvecio Lake and the Nado reservoir. However, this behavior was not seen in Carioca Lake; CONCLUSIONS: This study revealed the potential application of acoustic approaches to study the behavior of fish and zooplankton organisms in freshwater aquatic systems.
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migracao vertical das larvas de Chaoborus brasiliensis theobald 1901 diptera chaoboridae em um reservatorio tropical lagoa do nado belo horizonte estado de minas gerais
Acta Scientiarum. Biological Sciences, 2008Co-Authors: Jose Fernandes Bezerra Neto, Ricardo Motta PintocoelhoAbstract:Many investigations have shown that Chaoborus larvae develop diel vertical migration (DVM) to avoid fish predation and that this migration's amplitude is often associated with the instar stage. In this study, the Chaoborus brasiliensis vertical distribution was monitored in a shallow reservoir (Nado Lagoon, Belo Horizonte, Brazil), during the diel cycle, from October 1999 to September 2000. The mean depth in which each stage was found was estimated day and night and compared to their migration amplitude. No association was found between instar phase and DVM amplitude. Nevertheless, a clear association was found between the dissolved oxygen critical concentration and the amplitude of Chaoborus DVM. 1.0 mg.1(-1) was considered the concentration below which fish cannot survive. This finding gives support to the hypothesis that vertical migration is a defense mechanism against predation, since the larvae use the anoxic layer as a refuge against fish predation.
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vertical das larvas de Chaoborus brasiliensis Chaoborus brasiliensis Chaoborus brasiliensis Chaoborus brasiliensis theobald 1901 diptera em um reservatorio tropical chaoboridae em um reservatorio tropical chaoboridae em um reservatorio tropical chaob
2002Co-Authors: Minas Gerais, Jose Fernandes Bezerraneto, Ricardo Motta PintocoelhoAbstract:Vertical migration of Chaoborus brasiliensis (Diptera, Chaoboridae) larvae in Nado Lagoon, a tropical reservoir in Belo Horizonte, state of Minas Gerais, Brazil. Many investigations have shown that Chaoborus larvae develop diel vertical migration (DVM) to avoid fish predation and that this migration's amplitude is often associated with the instar stage. In this study, the Chaoborus brasiliensis vertical distribution was monitored in a shallow reservoir (Nado Lagoon, Belo Horizonte, Brazil), during the diel cycle, from October 1999 to September 2000. The mean depth in which each stage was found was estimated day and night and compared to their migration amplitude. No association was found between instar phase and DVM amplitude. Nevertheless, a clear association was found between the dissolved oxygen critical concentration and the amplitude of Chaoborus DVM. 1.0 mg.1(-1) was considered the concentration below which fish cannot survive. This finding gives support to the hypothesis that vertical migration is a defense mechanism against predation, since the larvae use the anoxic layer as a refuge against fish predation.
Lisa Deussen - One of the best experts on this subject based on the ideXlab platform.
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zooplankters nightmare the fast and efficient catching basket of larval phantom midges diptera Chaoborus
PLOS ONE, 2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Filter feeding zooplankton are a crucial component of limnic food webs. Copepods and cladocerans are important prey organisms for first-level predators like the common and abundant larvae of phantom midges (Chaoborus sp.). The latter possess a complex catching basket built of head appendages specialized to capture small crustaceans. The predator-prey-relationship of Chaoborus (Diptera, Nematocera) and Daphnia (Crustacea, Cladocera) has been studied in particular detail owing to the daphniids’ ability to react upon the threat of predation with inducible defenses. Daphnia pulex expresses so-called ‘neckteeth’ in the presence of Chaoborus larvae that are discussed as a defensive trait that interferes with the larval head appendages and their effectiveness has been shown in several studies. Nonetheless, mode of function of these neckteeth is not understood and the hypothesis that they interfere with the predator’s head appendages still has to be confirmed. To clarify the role of neckteeth in Daphnia, an understanding of the Chaoborus capture apparatus is essential. Here, we present a detailed three-dimensional analysis of Chaoborus obscuripes’ larval head morphology as well as a kinematic analysis of the attack motion, which revealed an impressive strike velocity (14 ms to prey contact). The movement of the larvae’s head appendages is reconstructed in the three-dimensional space using a combination of high-speed videography, micro-computed tomography and computer animation. Furthermore, we provide predation trial data to distinguish between pre- and post-attack defensive effects in D. pulex. Our findings suggest a combination of pre- and post-attack defenses with an average effectiveness of 50% each. With this study, we quantitatively describe prey capture kinematics of C. obscuripes and take a further step to reveal the neckteeth’ mode of function in D. pulex.
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 7
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Chaoborus obscuripes catching efficiency (n = 11, t-test, level of significances: p
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Zooplankters’ nightmare: The fast and efficient catching basket of larval phantom midges (Diptera: Chaoborus) - Fig 6
2019Co-Authors: Sebastian Kruppert, Linda C Weiss, Thomas Kleinteich, Stanislav N. Gorb, Lisa Deussen, Martin Horstmann, Jonas O Wolff, Ralph TollrianAbstract:Surface model of the Chaoborus obscuripes larval head capsule with closed (left) and opened (right) catching basket. Scale bar = 500 μm.
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High-speed-video_footage_Chaoborus_larva_attacking_Dpulex
2018Co-Authors: Sebastian Kruppert, Lisa Deussen, Jonas O Wolff, Stanislav N. GorbAbstract:48 videos of Chaoborus larva attacks on Daphnia pulex in the second juvenile instar in either defended (ind) or undefended (ctrl) morph
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Predation_trial_Videos_Chaoborus_vs_Dpulex
2018Co-Authors: Sebastian Kruppert, Lisa Deussen, Ralph TollrianAbstract:Video footage of predation trials in which a Chaoborus larva faces 20 juvenile Daphnia pulex either in defended (ind) or undefended (ctrl) morph.