Communal Web Research Articles

Aggression in a western Amazonian colonial spider, Philoponella republicana (Araneae: Uloboridae)

Group-living spiders are rare, and can be divided into multiple subcategories based on their tolerance of group mates. While social spiders are cooperative, colonial spiders are often antagonistic towards conspecifics. We examined colony dynamics in a colonial species, Philoponella republicana (Simon, 1891), focusing on aggressive behaviors to further understand this understudied species. We studied whether web region, sex ratio, web size, or spider size affected aggression. We also tested whether colony members discriminate against conspecific intruders, since this behavior, known as group closure, is prevalent in many other group-living animals but had not yet been tested in colonial spiders. Colony mates were often aggressive due to competition for limited resources, such as mates and orb webs, yet several characteristics of this species may reduce these competitive forces. First, female-biased secondary sex ratios appear to reduce male-male and female-male competition. Moreover, although some individuals defended orb webs, other areas in the communal web were not defended. Philoponella republicana also did not exhibit group closure. Our results further confirm that aggression between males decreases in colonies with more female-biased secondary sex ratios, and larger individuals correlate with a higher frequency of aggressive interactions. Moreover, we raise new questions concerning the evolutionary pressures that shape coloniality in spiders.

Diverging cooperative prey capture strategies in convergently evolved social spiders

Sociality in spiders has evolved independently multiple times, resulting in convergently evolved cooperative breeding and prey capture. In all social spiders, prey is captured by only a subset of group members and then shared with other, non-attacking group members. However, spiders' propensity to attack prey may differ among species due to species-specific trade-offs between risks, costs and benefits of prey capture involvement. We explored whether engagement in prey attack differs among three social Stegodyphus species, using orthopteran prey, and found substantial differences. Stegodyphus mimosarum Pavesi, 1883 had a low prey acceptance rate, was slow to attack prey, and engaged very few spiders in prey attack. In S. sarasinorum Karsch, 1892, prey acceptance was high, independently of prey size, but more spiders attacked when prey was small. While medium-sized prey had higher acceptance rate in S. dumicola Pocock, 1898, indicating a preference, the number of attackers was not affected by prey size. Our results suggest that the three species may have different cooperative prey capture strategies. In S. mimosarum and S. dumicola, whose geographical ranges overlap, these strategies may represent niche specialization, depending on whether their respective cautious and choosy approaches extend to other prey types than orthopterans, while S. sarasinorum may have a more opportunistic approach. We discuss factors that can affect social spiders' foraging strategy, such as prey availability, predation pressure, and efficiency of the communal web to ensnare prey. Future studies are required to investigate to which extent species-specific cooperative foraging strategies are shaped by ontogeny, group size, and plastic responses to environmental factors.

Maximizing the Impact Spread in Communal Web an Agent Based Proposal

Communal Impact replicating and maximization has more control over e-business and marketing. Present studies focus mainly on optimization of positive communal impact so as to market products adoptions supported stable web photos. Present procedures just raise impact in communal web briefly term, yet can’t produce sustainable or future results. Inside our proposed system we concentrate on maintaining future impact in communal web also suggest an agent based impact preservation replica which may choose predominant junction supports present reputation within operative communal webs in various measure. Constant impact is achieved more using several pulse pip choices than that of one pulse pip choices. The proposed system automatically keeps enduring impact in order to get impact preservation. It is applicable to achieve durable trade aim.

Behavioural modification of a social spider by a parasitoid wasp

1. Manipulation of host behaviour by parasitoids has long captured the imagination of ecologists. Parasitoid wasps in the Polysphincta group of genera develop as external parasitoids of spiders.2. In the present study, the previously undescribed interaction between a Zatypota sp. wasp (Ichneumonidae) and a social spider Anelosimus eximius (Theridiidae) is described. The larva of this Zatypota wasp is found to induce its host to disperse from their communal web and build an entirely enclosed web consisting of densely spun silk.3. The wasp is observed to target primarily immature A. eximius individuals, with 37.5–44% of nests in a given area being parasitised. Of those nests, approximately 1.3–2.0% of individuals are hosts to the parasitoid larvae. Larger spider colonies had a significantly higher probability of harbouring parasitoids.4. This interaction results in unusual behaviours for A. eximius induced by the parasitoid: (i) leaving the protection of the social nest and (ii) building a unique, altered web that it would not otherwise build.It is suggested that the wasp may be tapping into ancestral dispersal behaviours in its host and that a social species provides this wasp an evolutionary advantage by allowing a stable host source.

RETRACTED ARTICLE: Designing a Framework for Communal Software: Based on the Assessment Using Relation Modelling

Predicting and Identifying behavioral analysis in social media using big data analytics is exceptionally repetitive. Since data in motion are difficult to capture and process with existing innovation. In spite of the fact that there are numerous frameworks that have executed for user behavior analysis, it’s as yet an upcoming and unexplored market that has more prominent potential for better advancements. So with the help of Hadoop framework, a new approach of designing a communal framework is proposed and it’s used for predicting and identifying user’s behavioral analysis in a community. The proposed work can be applied in the community-based environment where the prediction and identification of user behavior analysis has to be made with the semantic web approach. In addition to that, a suitable model for the communally accountable software objects where these objects would observe online communal network information is designed. Further, these objects in online communal network, assess them from the viewpoint of communally accountable performance based on the relation modeling conceptions. The location of communally accountable mediators is grounded in diverse methods. Diverse illustrations are grabbed from the analysis with microblog assessments, community semantic web, higher relations for communal web and social network sourced big information assessments. In the proposed framework, the analysis is based on the assessment/observation of the communally accountable performance of the communal media big data and design of higher-level relations as the model for the above mentioned assessments.

Leadership for Undergraduate STEM Reform: Weaving a Communal Web

Successful reform of undergraduate science, technology, engineering, and mathematics (STEM) education requires good leaders; therefore, leadership development will be key if the national calls for reform (e.g., Vision and Change) are to be answered. The Partnership for Life Sciences Education (PULSE) is focused on whole‐department reform, which will require recruiting and supporting grassroots reformers who lead their colleagues through the change process. Department leaders will require (a) support networks that extend within and beyond each institution, (b) development of leadership skills and competencies, and (c) a mutually agreed‐upon strategic plan that inspires all to action. The STEM Department Evaluation Rubric is presented here as a tool to help establish that shared vision. Successful leaders will also need resilience, good humor and moral imagination, because the challenges are many but the rewards are substantial and sit at the core of the mission of our institutions.

Predatory behaviour of Cretaceous social orb-weaving spiders: response to Penney

Further evidence is provided showing that the Early Cretaceous juvenile and male spiders entrapped together in a web in a piece of amber from Myanmar are conspecific (Geratonephila burmanica) and members of a communal web, thus indicating spider sociality. Pictorial evidence of physical contact between the juvenile spider and the wasp entrapped in its web and the type of prey utilized by present day nephilids, leaves no doubt about the predatory behavior of the spider.

War in Silence?

As contemporary geopolitics is intrinsically linked to media-produced imagery, the mass media have emerged ts the largest and most powerful vehicle for distributing the sights and sounds of war. (1) Video footage representing sites of destruction, terrorist threats, and witness testimonies are increasingly becoming contemporary war's medium of choice. While video, television, and online news are conspicuously full of images penetrated by sound to the point of inseparability, still photography (still in the sense of free of noise or turbulence as well as immobile) remains a powerful way of transmitting traumatic events. Testimonies of war and disaster, both aural and visual, are rendered only visually in photographs. The way of seeing incorporates the way of listening: the photographer must produce images in such a way that their meanings will be congruent with those produced by both sight and sound. Yet photographs of exploding buildings, screaming bystanders, and lamenting mourners are not populated by deaf and mute characters moving about in a soundless space, nor must we as viewers remain insensitive to their sonic effects. Images from war zones can suggest a variety of acoustics, from noises (the loud, irregular, and startling sounds of bombings) to tones (a lament with its specific musical quality, resonance, and pitch). How does the incorporation of sound into photographs change our comprehensive and receptive skills? Twentieth-century criticism has paid ample attention to the visual--on the one hand questioning vision as the sole means of reliable knowledge about the external world, while on the other pointing out how our reality is constituted, disciplined, and normalized by the power of surveillance. Consequently, sound is almost without exception theorized as subordinate to the visual. For example, in cinema studies, terms like on-screen and offscreen have been applied to dialogues, monologues, and music even though these sounds were in themselves never off-screen (only their source was off-screen). The aural has been muted by the very words used to describe it. Yet, sound is so well-suited to recount the traumas of war. Unlike vision, which has often been theorized as distancing the viewer from the viewed,' (2) the physics and phenomenology of sound in Western culture are frequently associated with proximity, contact, and, consequently, violent disturbance. Through the air, sound transmits to our ears and skin the agitation resulting from collisions of objects surrounding us (often against our will) at a 360-degree expanse. Sound enables/forces contact, from the bond between mother and fetus to urban noise pollution and sonic weapons. What happens if we bring the notion of sound back to the photographic rendition of war and violence? In cinema studies, a sound one hears in a film without seeing its origin is called an acousmatic sound. What would we then call sounds of which, conversely, the sources are visible (bodies, objects, explosions), but which do not reach our ears? [ILLUSTRATION OMITTED] All of the photographs accompanying this text show women in the aftermath of individual or systemic violence. This choice reflects the tendency of contemporary media to use women as signifiers for the ravages of wars, genocides, and racial and gender inequalities. This may partially explain the recognition of these images by both professional and wider audiences-all of them have received awards in the prestigious World Press Photo contest. While conflating femininity and oppression risks reducing women to the pathological and the melancholic, women's screams and silences may also form a crucial expression of private pain that is consecutively transferred into a communal web of global and intermedial relationships. Hocine Zaourar's photograph, which was awarded World Press Photograph of the Year in 1997, shows a woman crying outside of the hospital where the dead and wounded were taken in the aftermath of a massacre in the Algerian village of Bentalha, in which approximately two hundred men, women, and children were methodically slaughtered in their homes in the middle of the night. …

Stealing for love? Apparent nuptial gift behavior in a kleptoparasitic spider

Abstract The presentation of nutritional resources as nuptial gifts before or during the mating process is well known among insects, but has only rarely been documented in spiders. Here, we report on observations and a series of photographs made during field studies in Fortin de las Flores, Veracruz, Mexico, which, although a single anecdotal report, represent a potentially significant finding. A male of the kleptoparasitic spider Argyrodes elevatus Taczanowski 1873 (Araneae, Theridiidae) was observed stealing a prey item from within a communal web of its host, the colonial orb-weaver Metepeira incrassata F.O. Pickard-Cambridge 1903 (Araneae, Araneidae). The male A. elevatus then carried and presented the prey item to a female, waited nearby until she began feeding, and copulated with her as she fed upon it. As far as is known, this is the first report of kleptoparasitic Argyrodes apparently utilizing a prey item stolen from a host spider as a nuptial gift.

A New Independently Derived Social Spider with Explosive Colony Proliferation and a Female Size Dimorphism1

ABSTRACTPermanent cooperative sociality is rare in spiders. Here we describe sociality in a cobweb (Theridiidae) genus with no other known social species. In five areas of eastern Ecuador, we found nests of Theridion nigroannulatum containing from a single to several thousand adults living together in a communal web. Spiders cooperated in prey capture and shared their food. Subadult to young adult sex ratios were highly female biased, suggesting a strongly subdivided population structure as in other permanent‐social spiders. Unusual aspects of T. nigroannulatum's biology include the existence of adult females of two discrete sizes, an extreme boom and bust pattern of colony growth, and the presence, within larger colonies, of populations of a predatory spider (Faiditus spp., Argyrodinae) that may play the role of a colony‐level parasite. The existence of females of two sizes may be the result of alternative female reproductive strategies, intracolony competition for resources, or an incipient caste system in this species. A redescription and phylogenetic analysis corroborate the placement of this species in Theridion, indicating that sociality has evolved independently in at least three theridiid genera.

WEB TRAWL

This month's web trawl examines three very different web sites that give information on Alzheimer's disease and other forms of dementia. http://www.dsdcengland.org.uk This is a communal web site for England's eight Dementia Service Development Centres (DSDCs), which provide services and information about dementia for a defined geographical area. From the home page, the user may access pages for each of the eight centres (each page contains a statement pertaining to the work of the centre, along with contact details). Links are also provided to a series of pages giving details of research projects undertaken by the various DSDCs, seminars, and other similar events. It does appear some time however since these pages were updated, and some of the information, particularly with regard to the seminars is out of date. Although the web site covers the eight English DSDCs, there are also links provided to the equivalent web sites in Scotland, Wales, and the Republic of Ireland. Overall, the information provide on this web site is very specialised and would be largely of interest only to those who are providing services for the care of patients with dementia.

Cooperative prey capture by young subsocial spiders: II. Behavioral mechanism

Subsocial spiders demonstrate an intermediate stage in the evolution of permanent sociality. Cooperative hunting is an important attribute of their sociality, but has not been documented in subsocial arthropods. After cannibalizing their mother, young of the subsocial spider Amaurobius ferox (Araneae, Amaurobiidae) remain together for several instars and feed communally. We monitored the collective prey capture behavior of the spiderlings. All the clutches showed collective capturing sequence (latency–orientation–moving–touching–seizing–feeding) toward the prey that was 10 times more massive than each individual. The first three individuals that exhibited attacking behavior were responsible for 90% of the total number of attacks, while 68% of the individuals within the group never exhibited attacks during the first 10 min following the introduction of prey into the communal web. First arriving individuals at the prey most often seized the antennae and legs of the prey, which probably facilitate access to the prey for subsequent individuals. The spiderlings that arrived later occupied more likely the abdomen and thorax, which contain more nutrition than the extremities occupied earlier. The individual apportionment of collective hunting behavior suggests a coordinated teamwork among individuals.

The Composition of a Colony of Philoponella raffrayi (Uloboridae) in Peninsular Malaysia.

A colony of Philoponella raffrayi (SIMON, 1891) was observed in the undergrowth of the secondary forest of the Forest Research Institute of Malaysia in Kuala Lumpur, Malaysia. The communal web was made up of 1) numerous females' orb-webs surrounding the colony, 2) strong sustainable silks which constitute irregular framework of the colony, and 3) irregular webs forming the center of the colony where males dominantly exist. The numbers of adult females, adult males, and juvenile females were 61, 15 and 2, respectively. The distribution of the developmental stages of the individuals in the colony indicates that the spiders have matured simultaneously. Three other species of spiders, Portia sp., Leucauge sp. and Argyrodes sp., were collected in the colony of P. raffrayi.

The biology of Simaetha paetula and S. thoracica, web‐building jumping spiders (Araneae, Salticidae) from Queensland: co‐habitation with social spiders, utilization of silk, predatory behaviour and intraspecific interactions

The biology of two aberrant species of salticid spiders is described from observations in tropical Queensland and in the laboratory. Typical salticids are cursorial hunting spiders that do not build prey‐catching webs, although they frequently build enclosing, tubular nests. Simaetha paetula (Kerserling) and S. thoracica Thorell, however, are both cursorial predators that build nests and spiders that build large prey‐catching webs. Nests and webs may be built alone or incorporated into the same structure. Adults, more often than juveniles, build isolated tubular nests. Juveniles, more often than adults, build webs without tubes. Nest‐webs are built most often on leaves and stems of plants, and the leaves are sometimes fastened to stems by strong silk clamps. Intraspecific interactions of S. paetula occur both at and away from nest‐webs. Away from nest‐webs, visual displays occur, but both visual and vibratory displays are important at nest‐webs. A repertoire of discrete displays occurs in both contexts. One prevalent display, clawing, is apparently multi‐channel: visual when the spiders are distant from each other and away from nest‐webs; tactile or chemotactic after the spiders come into contact with each other; and vibratory when they are at nest‐webs. During inter‐male interactions, displays occur that are unusually stereotyped for a salticid and require an unusual degree of co‐ordination of the movements of the two spiders. Males co‐habit in nest‐webs with sub‐adult females and mate when the female matures. Two different copulatory postures are routinely adopted, one of which is aberrant for salticids. Cannibalism is frequent, but the hypothesis that cannibalism reduction has been important in the evolution of display behaviour is not supported. Species of Simaetha Thorell often live within the colonies of the social spider Badumna Candida (L. Koch) as a kleptoparasite, gleaning insects from the edges of the alien webs and incorporating its own nest‐webs within the alien communal web. Although vulnerable to the glue on the social spider webs, Simaetha has behavioural specializations that enable it to avoid becoming prey of the social spiders. The biology of Simaetha is discussed in relation to salticid evolution.

Effects of prey characteristics and web structure on feeding and predatory responses of Nephila clavipes spiderlings

1. Field studies were conducted with second and third instar spiderlings of the orb weaver Nephila clavipes. The influences of prey type, prey condition, and web structure on feeding and predation were assessed. 2. After emergence from the egg sac, spiderlings inhabited a communal, tangled web. Juveniles readily ate dead or immobile siblings and insect prey but did not attack live prey. 3. Communal web inhabitants were transferred to solitary, viscid spiral orbs built by spiderlings after dispersal. Some predatory responses were expressed by these subjects, while inhabitants of solitary orbs tested in communal webs did not attack prey. It is concluded that web structure influences predatory responses in early instars.