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Gecko-Inspired Adhesive Mechanisms and Adhesives for Robots—A Review. ROBOTICS 2022. [DOI: 10.3390/robotics11060143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Small living organisms such as lizards possess naturally built functional surface textures that enable them to walk or climb on versatile surface topographies. Bio-mimicking the surface characteristics of these geckos has enormous potential to improve the accessibility of modern robotics. Therefore, gecko-inspired adhesives have significant industrial applications, including robotic endoscopy, bio-medical cleaning, medical bandage tapes, rock climbing adhesives, tissue adhesives, etc. As a result, synthetic adhesives have been developed by researchers, in addition to dry fibrillary adhesives, elastomeric adhesives, electrostatic adhesives, and thermoplastic adhesives. All these adhesives represent significant contributions towards robotic grippers and gloves, depending on the nature of the application. However, these adhesives often exhibit limitations in the form of fouling, wear, and tear, which restrict their functionalities and load-carrying capabilities in the natural environment. Therefore, it is essential to summarize the state of the art attributes of contemporary studies to extend the ongoing work in this field. This review summarizes different adhesion mechanisms involving gecko-inspired adhesives and attempts to explain the parameters and limitations which have impacts on adhesion. Additionally, different novel adhesive fabrication techniques such as replica molding, 3D direct laser writing, dip transfer processing, fused deposition modeling, and digital light processing are encapsulated.
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2
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Parthasarathy B, Somanathan H, Wright J. Long‐Term Behavioural Syndrome in Subadult Indian Social Spiders But Not Over the Short‐Term or in Juveniles. Ethology 2021. [DOI: 10.1111/eth.13229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Hema Somanathan
- School of Biology Indian Institute of Science Education and Research Thiruvananthapuram India
| | - Jonathan Wright
- Department of Biology Centre for Biodiversity Dynamics (CBD) Norwegian University of Science and Technology (NTNU) Trondheim Norway
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Abstract
Spiders (Araneae) make up a remarkably diverse lineage of predators that have successfully colonized most terrestrial ecosystems. All spiders produce silk, and many species use it to build capture webs with an extraordinary diversity of forms. Spider diversity is distributed in a highly uneven fashion across lineages. This strong imbalance in species richness has led to several causal hypotheses, such as codiversification with insects, key innovations in silk structure and web architecture, and loss of foraging webs. Recent advances in spider phylogenetics have allowed testing of some of these hypotheses, but results are often contradictory, highlighting the need to consider additional drivers of spider diversification. The spatial and historical patterns of diversity and diversification remain contentious. Comparative analyses of spider diversification will advance only if we continue to make progress with studies of species diversity, distribution, and phenotypic traits, together with finer-scale phylogenies and genomic data.
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Affiliation(s)
- Dimitar Dimitrov
- Department of Natural History, University Museum of Bergen, University of Bergen, 5020 Bergen, Norway;
| | - Gustavo Hormiga
- Department of Biological Sciences, The George Washington University, Washington, DC 20052, USA;
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Kono N, Nakamura H, Mori M, Tomita M, Arakawa K. Spidroin profiling of cribellate spiders provides insight into the evolution of spider prey capture strategies. Sci Rep 2020; 10:15721. [PMID: 32973264 PMCID: PMC7515903 DOI: 10.1038/s41598-020-72888-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 09/08/2020] [Indexed: 01/29/2023] Open
Abstract
Orb-weaving spiders have two main methods of prey capture: cribellate spiders use dry, sticky capture threads, and ecribellate spiders use viscid glue droplets. Predation behaviour is a major evolutionary driving force, and it is important on spider phylogeny whether the cribellate and ecribellate spiders each evolved the orb architecture independently or both strategies were derived from an ancient orb web. These hypotheses have been discussed based on behavioural and morphological characteristics, with little discussion on this subject from the perspective of molecular materials of orb web, since there is little information about cribellate spider-associated spidroin genes. Here, we present in detail a spidroin catalogue of six uloborid species of cribellate orb-weaving spiders, including cribellate and pseudoflagelliform spidroins, with transcriptome assembly complemented with long read sequencing, where silk composition is confirmed by proteomics. Comparative analysis across families (Araneidae and Uloboridae) shows that the gene architecture, repetitive domains, and amino acid frequencies of the orb web constituting silk proteins are similar among orb-weaving spiders regardless of the prey capture strategy. Notably, the fact that there is a difference only in the prey capture thread proteins strongly supports the monophyletic origin of the orb web.
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Affiliation(s)
- Nobuaki Kono
- Institute for Advanced Biosciences, Keio University, 403-1 Nipponkoku, Daihouji, Tsuruoka, Yamagata, 997-0017, Japan.
| | - Hiroyuki Nakamura
- Spiber Inc., 234-1 Mizukami, Kakuganji, Tsuruoka, Yamagata, 997-0052, Japan
| | - Masaru Mori
- Institute for Advanced Biosciences, Keio University, 403-1 Nipponkoku, Daihouji, Tsuruoka, Yamagata, 997-0017, Japan
| | - Masaru Tomita
- Institute for Advanced Biosciences, Keio University, 403-1 Nipponkoku, Daihouji, Tsuruoka, Yamagata, 997-0017, Japan
| | - Kazuharu Arakawa
- Institute for Advanced Biosciences, Keio University, 403-1 Nipponkoku, Daihouji, Tsuruoka, Yamagata, 997-0017, Japan
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Ludwig L, Barbour MA, Guevara J, Avilés L, González AL. Caught in the web: Spider web architecture affects prey specialization and spider-prey stoichiometric relationships. Ecol Evol 2018; 8:6449-6462. [PMID: 30038747 PMCID: PMC6053566 DOI: 10.1002/ece3.4028] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 01/31/2018] [Accepted: 02/25/2018] [Indexed: 11/12/2022] Open
Abstract
Quantitative approaches to predator-prey interactions are central to understanding the structure of food webs and their dynamics. Different predatory strategies may influence the occurrence and strength of trophic interactions likely affecting the rates and magnitudes of energy and nutrient transfer between trophic levels and stoichiometry of predator-prey interactions. Here, we used spider-prey interactions as a model system to investigate whether different spider web architectures-orb, tangle, and sheet-tangle-affect the composition and diet breadth of spiders and whether these, in turn, influence stoichiometric relationships between spiders and their prey. Our results showed that web architecture partially affects the richness and composition of the prey captured by spiders. Tangle-web spiders were specialists, capturing a restricted subset of the prey community (primarily Diptera), whereas orb and sheet-tangle web spiders were generalists, capturing a broader range of prey types. We also observed elemental imbalances between spiders and their prey. In general, spiders had higher requirements for both nitrogen (N) and phosphorus (P) than those provided by their prey even after accounting for prey biomass. Larger P imbalances for tangle-web spiders than for orb and sheet-tangle web spiders suggest that trophic specialization may impose strong elemental constraints for these predators unless they display behavioral or physiological mechanisms to cope with nutrient limitation. Our findings suggest that integrating quantitative analysis of species interactions with elemental stoichiometry can help to better understand the occurrence of stoichiometric imbalances in predator-prey interactions.
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Affiliation(s)
- Lorraine Ludwig
- Department of ZoologyBiodiversity Research CentreUniversity of BritishColumbiaBCCanada
| | - Matthew A. Barbour
- Department of ZoologyBiodiversity Research CentreUniversity of BritishColumbiaBCCanada
- Universidad Regional Amazónica IKIAMTenaNapoEcuador
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichSwitzerland
| | - Jennifer Guevara
- Universidad Regional Amazónica IKIAMTenaNapoEcuador
- Department of BiologyCenter for Computational and Integrative BiologyRutgers UniversityCamdenNJUSA
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichSwitzerland
| | - Leticia Avilés
- Department of ZoologyBiodiversity Research CentreUniversity of BritishColumbiaBCCanada
| | - Angélica L. González
- Department of BiologyCenter for Computational and Integrative BiologyRutgers UniversityCamdenNJUSA
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6
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Bott RA, Baumgartner W, Bräunig P, Menzel F, Joel AC. Adhesion enhancement of cribellate capture threads by epicuticular waxes of the insect prey sheds new light on spider web evolution. Proc Biol Sci 2017; 284:rspb.2017.0363. [PMID: 28566485 DOI: 10.1098/rspb.2017.0363] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 05/04/2017] [Indexed: 11/12/2022] Open
Abstract
To survive, web-building spiders rely on their capture threads to restrain prey. Many species use special adhesives for this task, and again the majority of those species cover their threads with viscoelastic glue droplets. Cribellate spiders, by contrast, use a wool of nanofibres as adhesive. Previous studies hypothesized that prey is restrained by van der Waals' forces and entrapment in the nanofibres. A large discrepancy when comparing the adhesive force on artificial surfaces versus prey implied that the real mechanism was still elusive. We observed that insect prey's epicuticular waxes infiltrate the wool of nanofibres, probably induced by capillary forces. The fibre-reinforced composite thus formed led to an adhesion between prey and thread eight times stronger than that between thread and wax-free surfaces. Thus, cribellate spiders employ the originally protective coating of their insect prey as a fatal component of their adhesive and the insect promotes its own capture. We suggest an evolutionary arms race with prey changing the properties of their cuticular waxes to escape the cribellate capture threads that eventually favoured spider threads with viscous glue.
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Affiliation(s)
- Raya A Bott
- Institute of Biology II, RWTH Aachen University, Worringerweg 3, Aachen, Germany
| | - Werner Baumgartner
- Institute of Biomedical Mechatronics, JKU Linz, Altenberger Straße 69, Linz, Austria
| | - Peter Bräunig
- Institute of Biology II, RWTH Aachen University, Worringerweg 3, Aachen, Germany
| | - Florian Menzel
- Institute of Zoology, University of Mainz, Johannes-von-Müller-Weg 6, Mainz, Germany
| | - Anna-Christin Joel
- Institute of Biology II, RWTH Aachen University, Worringerweg 3, Aachen, Germany
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Piorkowski D, Blackledge TA. Punctuated evolution of viscid silk in spider orb webs supported by mechanical behavior of wet cribellate silk. Naturwissenschaften 2017; 104:67. [DOI: 10.1007/s00114-017-1489-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 07/01/2017] [Accepted: 07/04/2017] [Indexed: 01/09/2023]
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8
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Bond JE, Opell BD. TESTING ADAPTIVE RADIATION AND KEY INNOVATION HYPOTHESES IN SPIDERS. Evolution 2017; 52:403-414. [DOI: 10.1111/j.1558-5646.1998.tb01641.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/1997] [Accepted: 11/12/1997] [Indexed: 11/30/2022]
Affiliation(s)
- Jason E. Bond
- Department of Biology Virginia Polytechnic Institute and State University Blacksburg Virginia 24061‐0406
| | - Brent D. Opell
- Department of Biology Virginia Polytechnic Institute and State University Blacksburg Virginia 24061‐0406
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Blamires SJ, Piorkowski D, Chuang A, Tseng YH, Toft S, Tso IM. Can differential nutrient extraction explain property variations in a predatory trap? ROYAL SOCIETY OPEN SCIENCE 2015; 2:140479. [PMID: 26064618 PMCID: PMC4448829 DOI: 10.1098/rsos.140479] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/16/2015] [Indexed: 06/04/2023]
Abstract
Predators exhibit flexible foraging to facilitate taking prey that offer important nutrients. Because trap-building predators have limited control over the prey they encounter, differential nutrient extraction and trap architectural flexibility may be used as a means of prey selection. Here, we tested whether differential nutrient extraction induces flexibility in architecture and stickiness of a spider's web by feeding Nephila pilipes live crickets (CC), live flies (FF), dead crickets with the web stimulated by flies (CD) or dead flies with the web stimulated by crickets (FD). Spiders in the CD group consumed less protein per mass of lipid or carbohydrate, and spiders in the FF group consumed less carbohydrates per mass of protein. Spiders from the CD group built stickier webs that used less silk, whereas spiders in the FF group built webs with more radii, greater catching areas and more silk, compared with other treatments. Our results suggest that differential nutrient extraction is a likely explanation for prey-induced spider web architecture and stickiness variations.
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Affiliation(s)
- Sean J. Blamires
- Department of Life Science, Tunghai University, Taichung 40704, Taiwan, Republic of China
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Dakota Piorkowski
- Department of Life Science, Tunghai University, Taichung 40704, Taiwan, Republic of China
| | - Angela Chuang
- Department of Life Science, Tunghai University, Taichung 40704, Taiwan, Republic of China
| | - Yi-Hsuan Tseng
- Department of Life Science, National Chung-Hsing University, Taichung 40227, Taiwan, Republic of China
| | - Søren Toft
- Department of BioScience, Aarhus University, Building 1540, Ny Munkegade 116, Aarhus 8000 C, Denmark
| | - I-Min Tso
- Department of Life Science, Tunghai University, Taichung 40704, Taiwan, Republic of China
- Department of Life Science, National Chung-Hsing University, Taichung 40227, Taiwan, Republic of China
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10
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Affiliation(s)
- Samuel Zschokke
- Department of Environmental Sciences, Section of Conservation Biology; University of Basel; St. Johanns-Vorstadt 10 CH-4056 Basel Switzerland
| | - Kensuke Nakata
- Kyoto Women's University; Kitahiyoshi-cho 35 Higashiyama-ku Kyoto 605-8501 Japan
- Faculty of Human Environment; Nagasaki Institute of Applied Science; 536 Aba-machi Nagasaki 851-0193 Japan
- Tokyo Keizai University; Minami-machi 1-7-34 Kokubunji Tokyo 185-8502 Japan
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11
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Fernández R, Hormiga G, Giribet G. Phylogenomic analysis of spiders reveals nonmonophyly of orb weavers. Curr Biol 2014; 24:1772-7. [PMID: 25042584 DOI: 10.1016/j.cub.2014.06.035] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 06/12/2014] [Accepted: 06/12/2014] [Indexed: 01/25/2023]
Abstract
Spiders constitute one of the most successful clades of terrestrial predators. Their extraordinary diversity, paralleled only by some insects and mites, is often attributed to the use of silk, and, in one of the largest lineages, to stereotyped behaviors for building foraging webs of remarkable biomechanical properties. However, our understanding of higher-level spider relationships is poor and is largely based on morphology. Prior molecular efforts have focused on a handful of genes but have provided little resolution to key questions such as the origin of the orb weavers. We apply a next-generation sequencing approach to resolve spider phylogeny, examining the relationships among its major lineages. We further explore possible pitfalls in phylogenomic reconstruction, including missing data, unequal rates of evolution, and others. Analyses of multiple data sets all agree on the basic structure of the spider tree and all reject the long-accepted monophyly of Orbiculariae, by placing the cribellate orb weavers (Deinopoidea) with other groups and not with the ecribellate orb weavers (Araneoidea). These results imply independent origins for the two types of orb webs (cribellate and ecribellate) or a much more ancestral origin of the orb web with subsequent loss in the so-called RTA clade. Either alternative demands a major reevaluation of our current understanding of the spider evolutionary chronicle.
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Affiliation(s)
- Rosa Fernández
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
| | - Gustavo Hormiga
- Department of Biological Sciences, The George Washington University, Washington, D.C. 20052, USA
| | - Gonzalo Giribet
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
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12
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Adjustment of web-building initiation to high humidity: a constraint by humidity-dependent thread stickiness in the spider Cyrtarachne. Naturwissenschaften 2014; 101:587-93. [PMID: 24916857 DOI: 10.1007/s00114-014-1196-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 05/02/2014] [Accepted: 06/02/2014] [Indexed: 10/25/2022]
Abstract
Cyrtarachne is an orb-weaving spider belonging to the subfamily Cyrtarachninae (Araneidae) which includes triangular-web-building Pasilobus and bolas spiders. The Cyrtarachninae is a group of spiders specialized in catching moths, which is thought to have evolved from ordinary orb-weaving araneids. Although the web-building time of nocturnal spiders is in general related to the time of sunset, anecdotal evidence has suggested variability of web-building time in Cyrtarachne and its closely related genera. This study has examined the effects of temperature, humidity, moonlight intensity, and prey (moths) availability on web-building time of Cyrtarachne bufo, Cyrtarachne akirai, and Cyrtarachne nagasakiensis. Generalized linear mixed model (GLMM) have revealed that humidity, and not prey availability, was the essential variable that explained the daily variability of web-building time. Experiments measuring thread stickiness under different humidities showed that, although the thread of Cyrtarachne was found to have strong stickiness under high humidity, low humidity caused a marked decrease of thread stickiness. By contrast, no obvious change in stickiness was seen in an ordinary orb-weaving spider, Larinia argiopiformis. These findings suggest that Cyrtarachne adjusts its web-building time to favorable conditions of high humidity maintaining strong stickiness, which enables the threads to work efficiently for capturing prey.
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13
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Wolff JO, Nentwig W, Gorb SN. The great silk alternative: multiple co-evolution of web loss and sticky hairs in spiders. PLoS One 2013; 8:e62682. [PMID: 23650526 PMCID: PMC3641104 DOI: 10.1371/journal.pone.0062682] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Accepted: 03/22/2013] [Indexed: 11/25/2022] Open
Abstract
Spiders are the most important terrestrial predators among arthropods. Their ecological success is reflected by a high biodiversity and the conquest of nearly every terrestrial habitat. Spiders are closely associated with silk, a material, often seen to be responsible for their great ecological success and gaining high attention in life sciences. However, it is often overlooked that more than half of all Recent spider species have abandoned web building or never developed such an adaptation. These species must have found other, more economic solutions for prey capture and retention, compensating the higher energy costs of increased locomotion activity. Here we show that hairy adhesive pads (scopulae) are closely associated with the convergent evolution of a vagrant life style, resulting in highly diversified lineages of at least, equal importance as the derived web building taxa. Previous studies often highlighted the idea that scopulae have the primary function of assisting locomotion, neglecting the fact that only the distal most pads (claw tufts) are suitable for those purposes. The former observations, that scopulae are used in prey capture, are largely overlooked. Our results suggest the scopulae evolved as a substitute for silk in controlling prey and that the claw tufts are, in most cases, a secondary development. Evolutionary trends towards specialized claw tufts and their composition from a low number of enlarged setae to a dense array of slender ones, as well as the secondary loss of those pads are discussed further. Hypotheses about the origin of the adhesive setae and their diversification throughout evolution are provided.
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Affiliation(s)
- Jonas O Wolff
- Functional Morphology and Biomechanics, Zoological Institute, University of Kiel, Kiel, Germany.
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14
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Piacentini LN, Ramírez MJ, Silva D. Systematics of Cauquenia (Araneae : Zoropsidae), with comments on the patterns of evolution of cribellum and male tibial crack on Lycosoidea. INVERTEBR SYST 2013. [DOI: 10.1071/is13031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A new genus of the spider family Zoropsidae, Cauquenia, gen. nov., is proposed for Cauquenia maule, sp. nov., from the Maule region in central Chile. The familial placement is tested through the inclusion of Cauquenia in the latest major published morphological analyses of the superfamily Lycosoidea, and the subfamily placement of the South American zoropsid genus Itatiaya Mello-Leitão is also tested including them in the Raven and Stumkat (2005) analysis. Cauquenia and Itatiaya are closely related to the African genera Griswoldia Dippenaar-Schoeman & Jocqué and Phanotea Simon, with which it shares a cup-shaped median apophysis on the male pedipalp and tooth-like projections on the lateral lobes of the epigyne in females. The patterns of evolution of the cribellum and the male tibial crack in Lycosoidea are explored; the cribellum shows up as primitively present, with three losses and four independent acquisitions, and the male tibial crack is lost twice. An asymmetric cost in cribellum gain : loss of 6 : 1 produces a primitive cribellum with 12 losses.
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15
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Agnarsson I, Gregorič M, Blackledge TA, Kuntner M. The phylogenetic placement of Psechridae within Entelegynae and the convergent origin of orb-like spider webs. J ZOOL SYST EVOL RES 2012. [DOI: 10.1111/jzs.12007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Ingi Agnarsson
- Department of Biology; University of Vermont; Burlington VT USA
- National Museum of Natural History; Smithsonian Institution; Washington DC USA
| | - Matjaž Gregorič
- Institute of Biology; Scientific Research Centre; Slovenian Academy of Sciences and Arts; Ljubljana Slovenia
| | - Todd A. Blackledge
- Department of Biology and Integrated Bioscience Program; University of Akron; Akron OH USA
| | - Matjaž Kuntner
- National Museum of Natural History; Smithsonian Institution; Washington DC USA
- Institute of Biology; Scientific Research Centre; Slovenian Academy of Sciences and Arts; Ljubljana Slovenia
- College of Life Sciences; Hubei University; Wuhan Hubei China
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16
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Dimitrov D, Lopardo L, Giribet G, Arnedo MA, Alvarez-Padilla F, Hormiga G. Tangled in a sparse spider web: single origin of orb weavers and their spinning work unravelled by denser taxonomic sampling. Proc Biol Sci 2012; 279:1341-50. [PMID: 22048955 PMCID: PMC3282380 DOI: 10.1098/rspb.2011.2011] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 10/11/2011] [Indexed: 11/12/2022] Open
Abstract
In order to study the tempo and the mode of spider orb web evolution and diversification, we conducted a phylogenetic analysis using six genetic markers along with a comprehensive taxon sample. The present analyses are the first to recover the monophyly of orb-weaving spiders based solely on DNA sequence data and an extensive taxon sample. We present the first dated orb weaver phylogeny. Our results suggest that orb weavers appeared by the Middle Triassic and underwent a rapid diversification during the end of the Triassic and Early Jurassic. By the second half of the Jurassic, most of the extant orb-weaving families and web designs were already present. The processes that may have given origin to this diversification of lineages and web architectures are discussed. A combination of biotic factors, such as key innovations in web design and silk composition, as well as abiotic environmental changes, may have played important roles in the diversification of orb weavers. Our analyses also show that increased taxon sampling density in both ingroups and outgroups greatly improves phylogenetic accuracy even when extensive data are missing. This effect is particularly important when addition of character data improves gene overlap.
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Affiliation(s)
- Dimitar Dimitrov
- Center for Macroecology, Evolution and Climate, Zoological Museum, University of Copenhagen, Copenhagen, Denmark.
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17
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Harmer AMT, Blackledge TA, Madin JS, Herberstein ME. High-performance spider webs: integrating biomechanics, ecology and behaviour. J R Soc Interface 2010; 8:457-71. [PMID: 21036911 DOI: 10.1098/rsif.2010.0454] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Spider silks exhibit remarkable properties, surpassing most natural and synthetic materials in both strength and toughness. Orb-web spider dragline silk is the focus of intense research by material scientists attempting to mimic these naturally produced fibres. However, biomechanical research on spider silks is often removed from the context of web ecology and spider foraging behaviour. Similarly, evolutionary and ecological research on spiders rarely considers the significance of silk properties. Here, we highlight the critical need to integrate biomechanical and ecological perspectives on spider silks to generate a better understanding of (i) how silk biomechanics and web architectures interacted to influence spider web evolution along different structural pathways, and (ii) how silks function in an ecological context, which may identify novel silk applications. An integrative, mechanistic approach to understanding silk and web function, as well as the selective pressures driving their evolution, will help uncover the potential impacts of environmental change and species invasions (of both spiders and prey) on spider success. Integrating these fields will also allow us to take advantage of the remarkable properties of spider silks, expanding the range of possible silk applications from single threads to two- and three-dimensional thread networks.
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Affiliation(s)
- Aaron M T Harmer
- Department of Biological Sciences, Macquarie University, Sydney 2109, Australia.
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18
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Agnarsson I, Blackledge TA. Can a spider web be too sticky? Tensile mechanics constrains the evolution of capture spiral stickiness in orb-weaving spiders. J Zool (1987) 2009. [DOI: 10.1111/j.1469-7998.2009.00558.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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19
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Blackledge TA, Scharff N, Coddington JA, Szüts T, Wenzel JW, Hayashi CY, Agnarsson I. Reconstructing web evolution and spider diversification in the molecular era. Proc Natl Acad Sci U S A 2009; 106:5229-34. [PMID: 19289848 PMCID: PMC2656561 DOI: 10.1073/pnas.0901377106] [Citation(s) in RCA: 218] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2008] [Indexed: 11/18/2022] Open
Abstract
The evolutionary diversification of spiders is attributed to spectacular innovations in silk. Spiders are unique in synthesizing many different kinds of silk, and using silk for a variety of ecological functions throughout their lives, particularly to make prey-catching webs. Here, we construct a broad higher-level phylogeny of spiders combining molecular data with traditional morphological and behavioral characters. We use this phylogeny to test the hypothesis that the spider orb web evolved only once. We then examine spider diversification in relation to different web architectures and silk use. We find strong support for a single origin of orb webs, implying a major shift in the spinning of capture silk and repeated loss or transformation of orb webs. We show that abandonment of costly cribellate capture silk correlates with the 2 major diversification events in spiders (1). Replacement of cribellate silk by aqueous silk glue may explain the greater diversity of modern orb-weaving spiders (Araneoidea) compared with cribellate orb-weaving spiders (Deinopoidea) (2). Within the "RTA clade," which is the sister group to orb-weaving spiders and contains half of all spider diversity, >90% of species richness is associated with repeated loss of cribellate silk and abandonment of prey capture webs. Accompanying cribellum loss in both groups is a release from substrate-constrained webs, whether by aerially suspended webs, or by abandoning webs altogether. These behavioral shifts in silk and web production by spiders thus likely played a key role in the dramatic evolutionary success and ecological dominance of spiders as predators of insects.
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Affiliation(s)
- Todd A Blackledge
- Department of Biology and Integrated Bioscience Program, University of Akron, Akron, OH 44325-3908, USA.
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Reconstructing web evolution and spider diversification in the molecular era. Proc Natl Acad Sci U S A 2009. [DOI: 10.1073/pnas.0901377106 er] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Opell BD, Schwend HS. Adhesive efficiency of spider prey capture threads. ZOOLOGY 2008; 112:16-26. [PMID: 18783928 DOI: 10.1016/j.zool.2008.04.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Revised: 03/05/2008] [Accepted: 04/16/2008] [Indexed: 11/15/2022]
Abstract
Cribellar capture threads are comprised of thousands of fine silk fibrils that are produced by the spigots of a spider's cribellum spinning plate and are supported by larger interior axial fibers. This study examined factors that constrain the stickiness of cribellar threads spun by members of the orb-weaving family Uloboridae in the Deinopoidea clade and compared the material efficiency of these threads with that of viscous capture threads produced by members of their sister clade, the Araneoidea. An independent contrast analysis confirmed the direct relationship between cribellar spigot number and cribellar thread stickiness. A model based on this relationship showed that cribellar thread stickiness is achieved at a rapidly decreasing material efficiency, as measured in terms of stickiness per spigot. Another limitation of cribellar thread was documented when the threads of two uloborid species were measured with contact plates of four widths. Unlike that of viscous threads, the stickiness of cribellar threads did not increase as plate width increased, indicating that only narrow bands along the edges of thread contact contributed to their stickiness. As thread volume increased, the gross material efficiency of cribellar threads decreased much more rapidly than that of viscous threads. However, cribellar threads achieved their stickiness at a much greater gross material efficiency than did viscous threads, making it more challenging to explain the transition from deinopoid to araneoid orb-webs.
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Affiliation(s)
- Brent D Opell
- Department of Biological Sciences, College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
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OPELL BRENTD, BOND JASONE. Capture thread extensibility of orb-weaving spiders: testing punctuated and associative explanations of character evolution. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.2000.tb00203.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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23
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OPELL BRENTD. Changes in spinning anatomy and thread stickiness associated with the origin of orb-weaving spiders. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.1999.tb01190.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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CARTAN CLAIREK, MIYASHITA TADASHI. Extraordinary web and silk properties of Cyrtarachne (Araneae, Araneidae): a possible link between orb-webs and bolas. Biol J Linn Soc Lond 2008. [DOI: 10.1111/j.1095-8312.2000.tb01255.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Opell BD, Schwend HS. The effect of insect surface features on the adhesion of viscous capture threads spun by orb-weaving spiders. J Exp Biol 2007; 210:2352-60. [PMID: 17575040 DOI: 10.1242/jeb.004952] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Spider orb-webs intercept a broad range of insects and their capture threads must adhere to a range of surface textures. In species of the Araneoidea clade, these capture threads are composed of viscid droplets whose size and spacing differ among species. To determine how droplet profile and insect surface texture interact, we measured the stickiness of viscous threads produced by four species using four insect surfaces that ranged from a smooth beetle elytra to the dorsal surface of a fly abdomen that was covered by large, widely spaced setae. The adhesion of threads to these surfaces differed by as much as 3.5-fold within a spider species and 2.1-fold for the same insect surface between spider species. However, 96% of these differences in stickiness was explained by four variables: the ratio of natural log of droplet volume to setal length, the natural log of droplet volume per mm of thread length, setal surface area, and the area of cuticle not excluded from thread contact by setae. Compared with previous measurements of primitive cribellar capture threads produced by orb weavers of the Deinopoidea clade,viscous threads performed more uniformly over the range of insect surfaces. They also held bug hemelytra, which were densely covered with fine setae, more securely, but held beetle elytra, fly wings and fly abdomens less securely than did viscous threads. Hemelytra may be held more securely because their setae more easily penetrate the viscous boundary layer to establish a greater area of interaction and, after having done so, offer more resistance as they are pulled through this layer. Finely textured surfaces may also have higher effective surface energies and therefore may interact more completely with viscous material.
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Affiliation(s)
- Brent D Opell
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
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Opell BD, Hendricks ML. Adhesive recruitment by the viscous capture threads of araneoid orb-weaving spiders. ACTA ACUST UNITED AC 2007; 210:553-60. [PMID: 17267640 DOI: 10.1242/jeb.02682] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The sticky prey capture threads of orb-webs are critical to web performance. By retaining insects that strike the web, these spirally arrayed threads allow a spider time to locate and subdue prey. The viscous capture threads spun by modern orb-weaving spiders of the Araneoidea clade replaced the dry, fuzzy cribellar capture threads of the Deinopoidea and feature regularly spaced moist, adhesive droplets. The stickiness of a cribellar thread is limited by its tendency to peel from a surface after the adhesion generated at the edges of contact is exceeded. In this study we test the hypothesis that viscous thread overcomes this limitation by implementing a suspension bridge mechanism (SBM) that recruits the adhesion of multiple thread droplets. We do so by using contact plates of four widths to measure the stickiness of six species' viscous threads whose profiles range from small, closely spaced droplets to large, widely spaced droplets. The increased stickiness registered by an increased number of thread droplets supports the operation of a SBM. However, the accompanying decrease in mean per droplet adhesion shows that droplets interior to the edges of thread contact contribute successively less adhesion. Models developed from these data suggest that the suspension bridge mechanism is limited to a span of approximately 12 droplets.
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Affiliation(s)
- Brent D Opell
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
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Tso IM, Chiang SY, Blackledge TA. Does the Giant Wood Spider Nephila pilipes Respond to Prey Variation by Altering Web or Silk Properties? Ethology 2007. [DOI: 10.1111/j.1439-0310.2007.01318.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Opell BD, Bond JE, Warner DA. The effects of capture spiral composition and orb-web orientation on prey interception. ZOOLOGY 2006; 109:339-45. [PMID: 16962752 DOI: 10.1016/j.zool.2006.04.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 03/15/2006] [Accepted: 04/10/2006] [Indexed: 11/28/2022]
Abstract
Cribellar prey capture threads found in primitive, horizontal orb-webs reflect more light, including ultraviolet wavelengths, than viscous threads found in more derived, vertical orb-webs. Low web visibility and vertical orientation are each thought to increase prey interception and may represent key innovations that contributed to the greater diversity of modern, araneoid orb-weaving spiders. This study compares prey interception rates of cribellate orb-webs constructed by Uloborus glomosus (Uloboridae) with viscous orb-webs constructed by Leucauge venusta (Tetragnathidae) and Micrathena gracilis (Araneidae). We placed sectors of cribellar and viscous threads side by side in frames that were oriented either horizontally or vertically. The webs of both U. glomosus and L. venusta intercepted more prey when vertically oriented. In each orientation L. venusta webs intercepted more insects than did U. glomosus. Although this is consistent with the greater visibility of cribellar threads, the more closely spaced capture spirals of L. venusta may have contributed to this difference. Micrathena gracilis webs intercepted more prey than did U. glomosus webs, although web orientation did not affect the performance of this araneoid species. The stickier and more closely spaced capture spirals of M. gracilis may have enhanced the interception rates of this species and accounted for the greater number of smaller dipterans retained in its webs. The tendency for these slow, weak flight insects to be blown into both horizontal and vertical webs may account for similar interception rates of horizontal and vertical M. gracilis webs. These observations support the enhanced prey interception of vertically oriented orb-webs, but offer only qualified support for the contributions of lower visibility viscous capture threads.
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Affiliation(s)
- Brent D Opell
- Department of Biology, Virginia Tech, Blacksburg, VA 24061, USA.
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29
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Tai PL, Hwang GY, Tso IM. Inter-specific sequence conservation and intra-individual sequence variation in a spider silk gene. Int J Biol Macromol 2005; 34:295-301. [PMID: 15556231 DOI: 10.1016/j.ijbiomac.2004.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Currently, studies on major ampullate spidroin 1 (MaSp1) genes of non-orb weaving spiders are few, and it is not clear whether genes of these organisms exhibit the same characteristics as those of orb-weavers. In addition, many studies have proposed that MaSp1 might be a single gene with allelic variants, but supporting evidence is still lacking. In this study, we compared partial DNA and amino acid sequences of MaSp1 cloned from different spider guilds. We also cloned partial MaSp1 sequences from genomic DNA and cDNA of the same individuals of spiders using the same primer combination to see if different molecular forms existed. In the repetitive region of partial MaSp1 sequences obtained, GGX, GA and poly-A motifs were present in all Araneomorphae and Mygalomorpae species examined. An extreme similarity in MaSp1 non-repetitive portions was found in sequences of ecribellate, cribellate and Mygalomorphae web-builders and such a result suggested that this sequence might exhibit an important function. A comparison of sequences amplified from the same individual showed that substitutions in amino acids occurred in both repetitive and non-repetitive regions, with a much higher variation in the former. These results suggest that the MaSp1 of Araneomorphae spiders exhibits several forms in an individual spider and it might be either a multiple gene or a single gene with a multiple exon/intron organization.
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Affiliation(s)
- Pei-Ling Tai
- Department of Life Science, Tunghai University, Taichung 407, Taiwan
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Díaz-Fleischer F. Predatory behaviour and prey-capture decision-making by the web-weaving spider Micrathena sagittata. CAN J ZOOL 2005. [DOI: 10.1139/z04-176] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Optimal-foraging theory predicts how a predator would feed most efficiently when faced with a choice of two types of prey differing in profitability and density in the habitat. The predator should focus only on the more profitable prey, since any prey item eaten by the predator has a cost in terms of the time and resources taken to subdue and eat it. A study of the hunting behaviour and prey-type selection of the web-weaving spider Micrathena sagittata (Walckenaer, 1841) (Araneae: Araneidae) in the field is documented. In the first part of the study, prey of two sizes were offered in four sectors of the web (top, bottom, right, and left). A prey item was provided at one position of the web at a time. Attack time was recorded at each position. Also, choice and no-choice tests were carried out by offering prey in opposing web sectors (top and bottom) simultaneously. Large prey were more successfully captured in the upper parts than in the bottom parts of the web. In the choice test, spiders always preferred large prey to small prey, while in the no-choice test, spiders always responded to the first stimulus received. Two different attack strategies, depending on prey size, were observed. Hunting strategies and prey-size preference can be related to the cost of web construction and profitability of the prey type.
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Hawthorn AC, Opell BD. van der Waals and hygroscopic forces of adhesion generated by spider capture threads. ACTA ACUST UNITED AC 2004; 206:3905-11. [PMID: 14555732 DOI: 10.1242/jeb.00618] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cribellar thread is the most primitive type of sticky prey capture thread found in aerial spider webs. Its outer surface is formed of thousands of fine fibrils that issue from a cribellum spinning field. The fibrils of primitive cribellar thread are cylindrical, whereas those of derived threads have nodes. Cribellar threads snag on insect setae but also adhere to smooth surfaces. A previous study showed empirically that cylindrical fibrils use only van der Waals forces to stick to smooth surfaces, as their stickiness is the same under different humidity. By contrast, noded fibrils are stickier under high humidity, where they are presumed to adsorb atmospheric water and implement hygroscopic (capillary) adhesion. Here, we model thread stickiness according to these two adhesive mechanisms. These models equate stickiness with the force necessary to overcome the adhesion of fibril contact points in a narrow band along each edge of the contact surface and to initiate peeling of the thread from the surface. Modeled and measured thread stickiness values are similar, supporting the operation of the hypothesized adhesive forces and portraying an important transition in the evolution of spider threads. Cribellar threads initially relied only on van der Waals forces to stick to smooth surfaces. The appearance of fibril nodes introduced hydrophilic sites that implemented hygroscopic force and increased thread stickiness under intermediate and high humidity.
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Affiliation(s)
- Anya C Hawthorn
- College of Veterinary Medicine, Virginia Tech, Blacksburg, VA 24061, USA
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RAMÍREZ MARTÍNJ, LOPARDO LARA, PLATNICK NORMANI. Notes on Chilean Anapids and Their Webs. AMERICAN MUSEUM NOVITATES 2004. [DOI: 10.1206/0003-0082(2004)428<0001:nocaat>2.0.co;2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Betz O, Kölsch G. The role of adhesion in prey capture and predator defence in arthropods. ARTHROPOD STRUCTURE & DEVELOPMENT 2004; 33:3-30. [PMID: 18089020 DOI: 10.1016/j.asd.2003.10.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2003] [Accepted: 10/28/2003] [Indexed: 05/14/2023]
Abstract
Adhesive devices are used by arthropods not only in terrestrial locomotion but also in prey capture and predator defence. We argue that the physical mechanisms involved in both these contexts must mainly be capillarity and the viscosity of an adhesive secretion, whereas other mechanisms, such as friction or intermolecular forces, are of minor importance. Adhesive prey-capture devices might function as passive devices or might be actively extended toward the prey, sometimes in a very rapid manner. Adhesive mechanisms used for predator defence might involve firm adhesion to the substratum or the discharge of a sticky secretion to immobilize the appendages of the opponent. We review the occurrence of adhesive devices as employed in both functional contexts across the Arthropoda and argue that these mechanisms are of particular importance for slow-moving and relatively clumsy life forms. We discuss three case studies in more detail. (1) Loricera larvae (Carabidae) use galeae with an extremely flexible cuticle in combination with an adhesive secretion. (2) Adult Stenus species (Staphylinidae) employ two highly flexible paraglossae that are covered by an adhesive emulsion of lipid droplets dispersed in an aqueous proteinaceous liquid. (3) Springtails often adhere to the mouthparts, the antennae, the legs, or other parts of the integument of Stenus larvae before being captured with the mandibles.
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Affiliation(s)
- Oliver Betz
- Zoologisches Institut der Universität, Abteilung Evolutionsbiologie der Invertebraten, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
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HAWTHORN ANYAC, OPELL BRENTD. Evolution of adhesive mechanisms in cribellar spider prey capture thread: evidence for van der Waals and hygroscopic forces. Biol J Linn Soc Lond 2002. [DOI: 10.1046/j.1095-8312.2002.00099.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Coddington JA, Chanzy HD, Jackson CL, Raty G, Gardner KH. The unique ribbon morphology of the major ampullate silk of spiders from the genus Loxosceles (recluse spiders). Biomacromolecules 2002; 3:5-8. [PMID: 11866550 DOI: 10.1021/bm010108m] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The morphology of silk produced by recluse spiders (Loxosceles arizonica) was investigated by scanning electron microscopy, atomic force microscopy, and transmission electron microscopy. This silk consisted entirely of very long, thin ribbons of width 2-4 microm and thicknesses of no more than 40 nm. The correspondence in shape and dimension between the silk ribbons and the elongated aperture of the major ampullate spigot indicated that these ribbons were major ampullate silk. Selected area electron diffraction patterns from single ribbons were indexed with an orthorhombic unit cell (a = 9.43(2) A, b = 8.96(3) A, c = 6.96(1) A). This unit cell is in good agreement with that previously reported for synthetic poly(L-alanylglycine). Thus it is likely that the crystalline regions of the major ampullate silk of L. arizonica consist of an alternating glycine-L-alanine motif that has adopted a beta-sheet structure. The amino acid composition achieved with the silk of L. arizonica as well as that of L. laeta confirmed that the major amino acid constituents of this silk were glycine and L-alanine in nearly equal amounts. As it was noticed that the dry ribbons were highly electrostatic, it is suggested that the electrostatic interaction plays an important role in prey capture for Loxoseles.
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Affiliation(s)
- Jonathan A Coddington
- Department of Entomology, National Museum Natural History, Smithsonian Institution, Washington, D.C. 20560, USA
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Chmiel K, Herberstein ME, Elgar MA. Web damage and feeding experience influence web site tenacity in the orb-web spider Argiope keyserlingi Karsch. Anim Behav 2000; 60:821-826. [PMID: 11124881 DOI: 10.1006/anbe.2000.1541] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
For orb-web spiders, the decision to remain at a particular site or to relocate elsewhere will ultimately depend on the quality of the site. In the past, the quality of the site has been measured in terms of prey availability; spiders experiencing large numbers of prey items are less likely to relocate. However, regular web damage caused by larger nonprey animals may also contribute to the quality of a particular site. Laboratory experiments revealed that the frequency and extent of web relocation by the orb-web spider Argiope keyserlingi was influenced by the feeding regime and the rate of nonprey web damage. Daily movement patterns were influenced by web damage, and these movements were in the direction away from the source of damage. However, the cumulative distance moved during the 7 days of the experiment was influenced by the frequency with which spiders were fed. Spiders that were not given prey moved further than spiders that obtained prey. These data indicate that spiders respond to web damage on a daily basis, but the cumulative movement of spiders over a longer period is influenced mostly by the history of prey ingestion rate. Copyright 2000 The Association for the Study of Animal Behaviour.
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Affiliation(s)
- K Chmiel
- Department of Zoology, University of Melbourne
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Herberstein ME, Craig CL, Coddington JA, Elgar MA. The function significance of silk decorations of orb-web spiders: a critical review of the empirical evidence. Biol Rev Camb Philos Soc 2000; 75:649-69. [PMID: 11117202 DOI: 10.1111/j.1469-185x.2000.tb00056.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A number of taxonomically diverse species of araneoid spiders adorn their orb-webs with conspicuous silk structures, called decorations or stabilimenta. The function of these decorations remains controversial and several explanations have been suggested. These include: (1) stabilising and strengthening the web; (2) hiding and concealing the spider from predators; (3) preventing web damage by larger animals, such as birds; (4) increasing foraging success; or (5) providing a sunshield. Additionally, they may have no specific function and are a consequence of stress or silk regulation. This review evaluates the strength of these explanations based on the evidence. The foraging function has received most supporting evidence, derived from both correlative field studies and experimental manipulations. This contrasts with the evidence provided for other functional explanations, which have not been tested as extensively. A phylogenetic analysis of the different decoration patterns suggests that the different types of decorations are as evolutionary labile as the decorations themselves: the analysis shows little homology and numerous convergences and independent gains. Therefore, it is possible that different types of decorations have different functions, and this can only be resolved by improved species phylogenies, and a combination of experimental and ultimately comparative analyses.
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Affiliation(s)
- M E Herberstein
- Department of Zoology, University of Melbourne, Victoria, Australia.
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Abstract
Spider silks are composite materials with often complex microstructures. They are spun from liquid crystalline dope using a complicated spinning mechanism which gives the animal considerable control. The material properties of finished silk are modified by the effects of water and other solvents, and spiders make use of this to produce fibres with specific qualities. The surprising sophistication of spider silks and spinning technologies makes it imperative for us to understand both material and manufacturing in nature before embarking on the commercialization of biotechnologically modified silk dope.
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