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A Novel Trade-Off for Batesian Mimics Running Title
Out of the frying pan and into the fire: A novel trade-off for Batesian mimics Running title: Salticids that mimic ants and get eaten by ant specialists Ximena J. Nelson*†, Daiqin Li§ and Robert R. Jackson† *Department of Psychology, Animal Behaviour Laboratory, Macquarie University, Sydney, NSW 2109, Australia Email: [email protected] Phone: 61-2-98509232 Fax: 61-2-98509231 §Department of Biological Sciences, National University of Singapore, Singapore †School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand Key words: Ants, Batesian mimicry, myrmecophagy, predation, spiders, trade-off Abstract A mimicry system was investigated in which the models were ants (Formicidae) and both the mimics and the predators were jumping spiders (Salticidae). By using motionless lures in simultaneous-presentation prey-choice tests, how the predators respond specifically to the static appearance of ants and ant mimics was determined. These findings suggest a rarely considered adaptive trade-off for Batesian mimics of ants. Mimicry may be advantageous when it deceives ant-averse potential predators, but disadvantageous in encounters with ant- eating specialists. Nine myrmecophagic (ant-eating) species (from Africa, Asia, Australia and North America) and one araneophagic (spider-eating) species (Portia fimbriata from Queensland) were tested with ants (5 species), with myrmecomorphic (ant-like) salticids (6 species of Myrmarachne) and with non-ant-like prey (dipterans and ordinary salticids). The araneophagic salticid chose an ordinary salticid and chose flies significantly more often than ants. P. fimbriata also chose the ordinary salticid and chose flies significantly more often than myrmecomorphic salticids. However, there was no significant difference in how P. -
SA Spider Checklist
REVIEW ZOOS' PRINT JOURNAL 22(2): 2551-2597 CHECKLIST OF SPIDERS (ARACHNIDA: ARANEAE) OF SOUTH ASIA INCLUDING THE 2006 UPDATE OF INDIAN SPIDER CHECKLIST Manju Siliwal 1 and Sanjay Molur 2,3 1,2 Wildlife Information & Liaison Development (WILD) Society, 3 Zoo Outreach Organisation (ZOO) 29-1, Bharathi Colony, Peelamedu, Coimbatore, Tamil Nadu 641004, India Email: 1 [email protected]; 3 [email protected] ABSTRACT Thesaurus, (Vol. 1) in 1734 (Smith, 2001). Most of the spiders After one year since publication of the Indian Checklist, this is described during the British period from South Asia were by an attempt to provide a comprehensive checklist of spiders of foreigners based on the specimens deposited in different South Asia with eight countries - Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan and Sri Lanka. The European Museums. Indian checklist is also updated for 2006. The South Asian While the Indian checklist (Siliwal et al., 2005) is more spider list is also compiled following The World Spider Catalog accurate, the South Asian spider checklist is not critically by Platnick and other peer-reviewed publications since the last scrutinized due to lack of complete literature, but it gives an update. In total, 2299 species of spiders in 67 families have overview of species found in various South Asian countries, been reported from South Asia. There are 39 species included in this regions checklist that are not listed in the World Catalog gives the endemism of species and forms a basis for careful of Spiders. Taxonomic verification is recommended for 51 species. and participatory work by arachnologists in the region. -
A Specialised Hunting Strategy Used to Overcome Dangerous Spider Prey
www.nature.com/scientificreports OPEN Nest usurpation: a specialised hunting strategy used to overcome dangerous spider prey Received: 18 January 2019 Ondřej Michálek 1, Yael Lubin 2 & Stano Pekár 1 Accepted: 14 March 2019 Hunting other predators is dangerous, as the tables can turn and the hunter may become the hunted. Published: xx xx xxxx Specialized araneophagic (spider eating) predators have evolved intriguing hunting strategies that allow them to invade spiders’ webs by adopting a stealthy approach or using aggressive mimicry. Here, we present a newly discovered, specialized hunting strategy of the araneophagic spider Poecilochroa senilis (Araneae: Gnaphosidae), which forces its way into the silk retreat of the potential spider prey and immobilizes it by swathing gluey silk onto its forelegs and mouthparts. Poecilochroa senilis has been reported from the nests of a several, often large, spider species in the Negev desert (Israel), suggesting specialization on spiders as prey. Nevertheless, in laboratory experiments, we found that P. senilis has a wider trophic niche, and fed readily on several small insect species. The specialized nest-invading attack was used more frequently with large spiders, and even small juvenile P. senilis were able to attack and subdue larger spiders. Our observations show that specifc hunting tactics, like nest usurpation, allow specialized predators to overcome defences of dangerous prey. Evolutionary arms races between prey and predators lead to the evolution of various defence mechanisms of the prey and counter-adaptations of predators to subdue such a prey1. Predator-prey arms races are ofen asym- metrical, as a prey organism is under stronger selection pressure2. -
Scene Analysis in the Natural Environment
REVIEW ARTICLE published: 01 April 2014 doi: 10.3389/fpsyg.2014.00199 Scene analysis in the natural environment Michael S. Lewicki 1*, Bruno A. Olshausen 2 , Annemarie Surlykke 3 and Cynthia F. Moss 4 1 Department of Electrical Engineering and Computer Science, Case Western Reserve University, Cleveland, OH, USA 2 Helen Wills Neuroscience Institute, School of Optometry, Redwood Center for Theoretical Neuroscience, University of California at Berkeley, Berkeley, CA, USA 3 Department of Biology, University of Southern Denmark, Odense, Denmark 4 Department of Psychology and Institute for Systems Research, University of Maryland, College Park, MD, USA Edited by: The problem of scene analysis has been studied in a number of different fields over the past Laurence T. Maloney, Stanford decades. These studies have led to important insights into problems of scene analysis, but University, USA not all of these insights are widely appreciated, and there remain critical shortcomings in Reviewed by: current approaches that hinder further progress. Here we take the view that scene analysis Wolfgang Einhauser, Philipps-Universität Marburg, is a universal problem solved by all animals, and that we can gain new insight by studying Germany the problems that animals face in complex natural environments. In particular, the jumping Sébastien M. Crouzet, Charité spider, songbird, echolocating bat, and electric fish, all exhibit behaviors that require robust University Medicine, Germany solutions to scene analysis problems encountered in the natural environment. -
Clark Thesis.Pdf (8.256Mb)
THE ROLE OF CHEMICAL CUES , IN THE PREDATORY AND ANTI-PREDATORY BEHAVIOUR OF JU~PING SPIDERS (ARANEAE, SAL TICIDAE) A Thesis submitted in fulfilment of the requirements of the degree of Doctor of Philosophy in, Zoology at the University of Canterbury by Robert John Clark 2000 CONTENTS Abstract 1· Chapter 1: Introduction 3 Chapter 2: Theoretical background 9 Chapter 3: Chemical cues elicit prey capture in P. fimbriata 56 Chapter 4: Web use during predatory encounters between P. fimbriata, an araneophagic 91 jumping spider, and its preferred prey, other jumping spiders Chapter 5: Speculative hunting by an araneophagic jumping spider 108 Chapter 6: Chemical cues from ants influence predatory behaviour in Habrocestum pulex 125 (Hentz), an ant eating jumping spider (Araneae, Salticidae) Chapter 7: Reactions of Habrocestum pulex, a myrmecophagic salticid, to potential 147 kairomones from ants Chapter 8: Dragllnes and assessment of fighting ability in cannibalistic jumping spiders 160 Chapter 9: Relationship between violent aggression in saltlcids and use of pheromones to 178 obtain information on conspeclfics Chapter10: Discussion 189 Acknowledgements 198 References 199 2 9 MAR 2000 1 ABSTRACT The role of chemical cues in prey-capture behaviour is studied in jumping spiders (Salticldae). Prior to this study, little attention has been given to how chemical cues influence the predatory behaviour of these spiders with complex eyes and visual acuity unrivalled In any other animals of comparable size. Three categories of predation are considered: salticids preying on conspecifics (cannibalism), salticids preying on non-conspecific spiders (araneophagy) and salticids preying on ants (myrmecophagy). Primary study animals are Portia spp. -
Nelson & Jackson Revisions2
Compound mimicry and trading predators by the males of sexually dimorphic Batesian mimics Running Title: Compound mimicry Ximena J. Nelson1,2, Robert R. Jackson1 1Department of Psychology, Animal Behaviour Laboratory, Macquarie University, Sydney, NSW 2109, Australia Email: [email protected] Phone: 61-2-98509232 Fax: 61-2-98509231 2School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand 1 ABSTRACT Sexual dimorphism is pronounced in Myrmarachne, a large genus of ant-like jumping spiders (Salticidae) and one of the major animal groups in which Batesian mimicry of ants has evolved. Although adult females and juveniles of both sexes are distinctly ant-like in appearance, Myrmarachne males have elongated chelicerae that might appear to detract from their resemblance to ants. Experimental findings suggest that the Myrmarachne male’s solution is to adopt compound mimicry (i.e., the male’s model seems to be not simply an ant worker but a combination of an ant and something in the ant’s mandibles: an ‘encumbered ant’). By becoming a mimic of a particular subset of worker ants, Myrmarachne males may have retained their Batesian-mimicry defence against ant-averse predators, but at the price of receiving the unwanted attention of predators for which encumbered ants are preferred prey. Two salticid species were used as predators in the experiments. Portia fimbriata is known to choose other salticids as preferred prey and to avoid un-encumbered ants and their mimics (Myrmarachne females). In experiments reported here, P. fimbriata avoided encumbered ants and Myrmarachne males. Ants are the preferred prey of Chalcotropis gulosus. -
An Investigation of Response Decrement in Jumping Spiders
1 An investigation of response decrement in jumping spiders A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science in Zoology at the University of Canterbury by Bonnie Humphrey University of Canterbury 2017 2 Table of contents Acknowledgements………………………………………………………………………3 Abstract………………………………………………………………………………………..5 Chapter 1. Introduction Arthropod cognition.…………………………………………………………………………………………………..………….….6 Habituation and response decrement.………………………………………………………..........................…….. 8 Attention and salience ………………………………………………………………………………………………………….….. 10 Study species.………………………………………………………………………………………..........................………….. 12 References………………………………………………………………………………………………………………………………….17 Chapter 2. Vigilance Introduction…………………………………………………………………………………………...........................…………. 22 Methods …………………………………………………………………………………………………………………………..………. 25 Results………………………………………………………………………………………………………...........................…….. 31 Discussion………………………………………………………………………………………………………………………………….. 34 References…………………………………………………………………………………………………………………………………. 39 Chapter 3. Biological relevance Introduction…………………………………………………………………………………………………………………………..….. 42 Methods …………………………………………………………………………………………………………………….………….…. 45 Results……………………………………………………………………………………………………………………………….……... 47 Discussion……………………………………………………………………………………………………………………….………... 50 References………………………………………………………………………………………………………………………….….…. 53 Chapter 4. Caffeine Introduction…………………………………………………………………………………………………………………………..…. -
Fringed Jumping Spider, Portia Fimbriata
Care guide Fringed Jumping Spider, Portia fimbriata Fringed Jumping Spiders are fascinating spiders which are found in northern Australia. They are regarded being the most intelligent spiders in the world due to their ability to problem solve and modify their behaviour while stalking their prey. They prey predominantly upon other spiders and will utilise different methods of attack depending on the species they are targeting. They jump upon their prey to bite it and employ a wide variety of strategies in order to get themselves into a suitable launch position. They will adjust their strategies if they are not successful and appear to learn from their experiences. When stalking orb-weaving spiders they will pluck at the orb- web in a variety of ways in order to entice the web’s owner to a vulnerable position. They will alter the style and frequency of plucking if they don’t get a response. They will also systematically explore the surrounds of the web continuously looking around for a good attack position. The movement of this species is different than most jumping spiders which typically move in an energetic manner. Fringed Jumping Spiders usually move in a slow rocking motion and this, combined with their cryptic body form makes them appear as wild blown debris. These spiders grow by shedding their outer skeleton (exoskeleton). This process is called ecdysis or moulting. They moult every few weeks until they mature. Prior to each moult their colour darkens and they stop feeding a few days. Once they begin to moult they usually complete the process in about 10 minutes. -
Is Behavioural Flexibility Evidence of Cognitive Complexity?
Downloaded from http://rsfs.royalsocietypublishing.org/ on April 21, 2017 Is behavioural flexibility evidence of cognitive complexity? How evolution can rsfs.royalsocietypublishing.org inform comparative cognition Irina Mikhalevich1, Russell Powell2 and Corina Logan3 1School of Mind and Brain, Humboldt-Universitat zu Berlin, Berlin, Germany 2Department of Philosophy, Boston University, Boston, MA 02215, USA Research 3Department of Zoology, University of Cambridge, Cambridge, UK Cite this article: Mikhalevich I, Powell R, RP, 0000-0002-9893-1721; CL, 0000-0002-5944-906X Logan C. 2017 Is behavioural flexibility Behavioural flexibility is often treated as the gold standard of evidence for evidence of cognitive complexity? How more sophisticated or complex forms of animal cognition, such as planning, evolution can inform comparative cognition. metacognition and mindreading. However, the evidential link between Interface Focus 7: 20160121. behavioural flexibility and complex cognition has not been explicitly or http://dx.doi.org/10.1098/rsfs.2016.0121 systematically defended. Such a defence is particularly pressing because observed flexible behaviours can frequently be explained by putatively sim- pler cognitive mechanisms. This leaves complex cognition hypotheses open One contribution of 12 to a theme issue to ‘deflationary’ challenges that are accorded greater evidential weight ‘Convergent minds: the evolution of cognitive precisely because they offer putatively simpler explanations of equal explana- complexity in nature’. tory power. This paper challenges the blanket preference for simpler explanations, and shows that once this preference is dispensed with, and the full spectrum of evidence—including evolutionary, ecological and phylo- Subject Areas: genetic data—is accorded its proper weight, an argument in support of biocomplexity, astrobiology the prevailing assumption that behavioural flexibility can serve as evidence for complex cognitive mechanisms may begin to take shape. -
Geographic Variation in a Spider╎s Ability to Solve a Confinement
International Journal of Comparative Psychology, 2006, 19 , 282-296. Copyright 2006 by the International Society for Comparative Psychology Geographic Variation in a Spider’s Ability to Solve a Confinement Problem by Trial and Error Robert R. Jackson, Fiona R. Cross, and Chris M. Carter University of Canterbury, New Zealand Portia is a genus of web-invading araneophagic (spider eating) jumping spiders known from earlier studies to derive aggressive-mimicry signals by using a generate-and-test (trial and error) algorithm. We studied individuals of Portia labiata from two populations (Los Baños and Sagada) in the Philip- pines that have previously been shown to differ in the level to which they rely on trial-and-error deri- vation of signals for prey capture (Los Baños relied on trial and error more strongly than Sagada P . labiata ). Here we investigated P. labiata ’s use of trial and error in a novel situation (a confinement problem: how to escape from an island surrounded by water) that is unlikely to correspond closely to anything the spider would encounter in nature. During Experiment 1, spiders chose between two potential escape tactics (leap or swim), one of which was set at random to fail (brought spider no closer to edge of tray) and the other of which was set for partially succeeding (brought spider closer to edge of tray). By using trial and error, the Los Baños P. labiata solved the confinement problem significantly more often than the Sagada P. labiata in Experiment 1, both when the correct choices were positively reinforced (i.e., when the spider was moved closer to edge of tray) and when incor- rect choices were punished (i.e., when the spider got no closer to edge of tray). -
Convergent Evolution of Eye Ultrastructure and Divergent Evolution of Vision-Mediated Predatory Behaviour in Jumping Spiders
doi: 10.1111/j.1420-9101.2007.01335.x Convergent evolution of eye ultrastructure and divergent evolution of vision-mediated predatory behaviour in jumping spiders K. F. SU,* R. MEIER,* R. R. JACKSON, à D. P. HARLAND §&D.LI* *Department of Biological Sciences, National University of Singapore, Singapore School of Biological Sciences, University of Canterbury, Christchurch, New Zealand àInternational Centre of Insect Physiology and Ecology (ICIPE), Thomas Odhiambo Campus, Mbita Point, Kenya §Structural Biology Group, Canesis Network Ltd, Lincoln, New Zealand Keywords: Abstract aggressive mimicry; All jumping spiders have unique, complex eyes with exceptional spatial acuity araneophagy; and some of the most elaborate vision-guided predatory strategies ever eyes; documented for any animal of their size. However, it is only recently that predatory behaviour; phylogenetic techniques have been used to reconstruct the relationships and Salticidae; key evolutionary events within the Salticidae. Here, we used data for 35 Spartaeinae. species and six genes (4.8 kb) for reconstructing the phylogenetic relationships between Spartaeinae, Lyssomaninae and Salticoida. We document a remark- able case of morphological convergence of eye ultrastructure in two clades with divergent predatory behaviour. We, furthermore, find evidence for a stepwise, gradual evolution of a complex predatory strategy. Divergent predatory behaviour ranges from cursorial hunting to building prey-catching webs and araneophagy with web invasion and aggressive mimicry. Web invasion and aggressive mimicry evolved once from an ancestral spartaeine that was already araneophagic and had no difficulty entering webs due to glue immunity. Web invasion and aggressive mimicry was lost once, in Paracyrba, which has replaced one highly specialized predation strategy with another (hunting mosquitoes). -
The Miracle Ir the Spider
To The Reader The reason why a special chapter is assigned to the collapse of the theory of evolution is that this theory constitutes the basis of all anti-spiritual philosophies. Since Darwinism rejects the fact of creation, and therefore the existence of Allah, during the last 140 years it has caused many people to abandon their faith or fall into doubt. Therefore, showing that this theory is a deception is a very important duty, which is strongly related to the religion. It is imperative that this important service be rendered to everyone. Some of our readers may find the chance to read only one of our books. Therefore, we think it appropriate to spare a chapter for a summary of this subject. In all the books by the author, faith-related issues are explained in the light of the Qur'anic verses and people are invited to learn Allah's words and to live by them. All the subjects that concern Allah's verses are explained in such a way as to leave no room for doubt or question marks in the reader's mind. The sincere, plain and fluent style employed ensures that everyone of every age and from every social group can easily understand the books. This effective and lucid narrative makes it possible to read them in a single sitting. Even those who rigorously reject spirituality are influenced by the facts recounted in these books and cannot refute the truthfulness of their contents. This book and all the other works of the author can be read individually or discussed in a group at a time of conversation.