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Robert R. Jackson - One of the best experts on this subject based on the ideXlab platform.
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Arthropod Intelligence? The Case for Portia.
Frontiers in psychology, 2020Co-Authors: Fiona R. Cross, Robert R. Jackson, Georgina E. Carvell, Randolph C. GraceAbstract:Macphail's "null hypothesis," that there are no differences in intelligence, qualitative, or quantitative, between non-human vertebrates has been controversial. This controversy can be useful if it encourages interest in acquiring a detailed understanding of how non-human animals express flexible problem-solving capacity ("intelligence"), but limiting the discussion to vertebrates is too arbitrary. As an example, we focus here on Portia, a spider with an especially intricate predatory strategy and a preference for other spiders as prey. We review research on pre-planned detours, expectancy violation, and a capacity to solve confinement problems where, in each of these three contexts, there is experimental evidence of innate cognitive capacities and reliance on internal representation. These cognitive capacities are related to, but not identical to, intelligence. When discussing intelligence, as when discussing cognition, it is more useful to envisage a continuum instead of something that is simply present or not; in other words, a continuum pertaining to flexible problem-solving capacity for "intelligence" and a continuum pertaining to reliance on internal representation for "cognition." When envisaging a continuum pertaining to intelligence, Daniel Dennett's notion of four Creatures (Darwinian, Skinnerian, Popperian, and Gregorian) is of interest, with the distinction between Skinnerian and Popperian Creatures being especially relevant when considering Portia. When we consider these distinctions, a case can be made for Portia being a Popperian Creature. Like Skinnerian Creatures, Popperian Creatures express flexible problem solving capacity, but the manner in which this capacity is expressed by Popperian Creatures is more distinctively cognitive.
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Portia's capacity to decide whether a detour is necessary.
The Journal of experimental biology, 2019Co-Authors: Fiona R. Cross, Robert R. JacksonAbstract:Proficiency at planning is known to be part of the exceptionally complex predatory repertoire of Portia, a genus of jumping spiders (Salticidae) that specialize in preying on other spiders. This includes proficiency at choosing between two detour routes, with only one leading to otherwise inaccessible prey. Less is known about Portia's proficiency at making strategic decisions pertaining to whether a detour is required or not. Using Portia africana, we investigated this by having lures (prey or leaf pieces) visible at the beginning of a trial but not later, and by using water to restrict P. africana's freedom of movement. A detour path was always present, but sometimes a causeway was also present, allowing direct access to lures. After seeing prey, P. africana more often took the causeway when present and, when absent, more often took the detour path. After seeing leaf pieces, P. africana never took the detour path.
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Portia’s capacity to decide whether a detour is necessary
The Journal of Experimental Biology, 2019Co-Authors: Fiona R. Cross, Robert R. JacksonAbstract:ABSTRACT Proficiency at planning is known to be part of the exceptionally complex predatory repertoire of Portia, a genus of jumping spiders (Salticidae) that specialize in preying on other spiders. This includes proficiency at choosing between two detour routes, with only one leading to otherwise inaccessible prey. Less is known about Portia’s proficiency at making strategic decisions pertaining to whether a detour is required or not. Using Portia africana, we investigated this by having lures (prey or leaf pieces) visible at the beginning of a trial but not later, and by using water to restrict P. africana’s freedom of movement. A detour path was always present, but sometimes a causeway was also present, allowing direct access to lures. After seeing prey, P. africana more often took the causeway when present and, when absent, more often took the detour path. After seeing leaf pieces, P. africana never took the detour path.
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Olfaction-based mate-odor identification by jumping spiders from the genus Portia
Journal of Arachnology, 2011Co-Authors: Robert R. Jackson, Fiona R. CrossAbstract:Jumping spiders (Salticidae) are known for having good eyesight, but the extent to which they also rely on olfaction is poorly understood. We report here new information on the olfactory abilities of the salticid genus Portia .W e investigated for the first time the ability of adult males and females of four Portia species (P. africana, P. schultzi, P. fimbriata and P. labiata) to discriminate between mate and non-mate odor. In a Y-shape olfactometer, males of all four species chose the odor from an opposite-sex conspecific significantly more often than they chose a no-odor control, but the number of males that chose the odor from an opposite-sex heterospecific or the odor from a same-sex conspecific was not significantly different from the number of males that chose the control. The number of female test spiders that chose the odor from an opposite-sex conspecific or the odor from a same-sex conspecific was not significantly different from the number of females that chose the control. The implications of these findings for understanding Portia's mating system are discussed.
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the biology of Portia fimbriata a web building jumping spider araneae salticidae from queensland utilization of webs and predatory versatility
Journal of Zoology, 2009Co-Authors: Robert R. Jackson, A D BlestAbstract:The biology of a primitive salticid spider, Portia fimbriata (Doleschall), is described from observations in a Queensland rain-forest and the laboratory. Locomotory specializations enable the spiders to move about readily on webs; and all stages of life history are associated with webs, both alien and two types they build themselves. The more flimsy Type 1 webs are used as resting sites similar to the nests employed by more familiar jumping spiders. Type 2 webs are more substantial structures in which the spider moults, mates, oviposits, broods its eggs and remains for as long as 48 days. The predatory strategy of Portia includes the use of distinct alternative tactics in the pursuit of varied types of prey. Most of these tactics are ones not usually associated with salticids. Portia invaded diverse types of webs without difficulty, including adhesive and non-adhesive, cribellate and ecribellate, and two-and three-dimensional ones. Once in the web, Portia produced vibratory stimuli by specialized but varied movements of the legs and palps. Web spiders responded to these in a manner more appropriate for a potential prey item or a conspecific in its web than a potential predator. Sometimes vibrations lured the spider to the waiting Portia. Other times, localized movements were elicited which assisted Portia in remaining orientated toward the spider as it stalked across the web. Outside webs, Portia stalked other species of salticids, moving in a very slow and “mechanical” fashion and arresting forward motion whenever faced by the prey. Evidently, the salticids did not recognize Portia as another salticid and a potential predator. Although Portia pursued insects, they pursued spiders more readily, persistently and successfully. Portia captured insects outside webs, on their own webs and on the webs of other species. Those on their own webs adhered temporarily to the silk. In webs of other spiders, insects were sometimes taken directly from the chelicerae of the host. Also, their own webs assisted Portia in capturing other spiders. Eggs of spiders were fed upon both on and off webs. Different attack tactics tended to be employed with different types of prey: web spiders, lunge; salticids, swoop; insects, pick-up. Egg-cases were opened by means of specialized movements involving the chelicerae and the eggs were raked toward the mouth with the legs. Most prey were seized after the attack, but sometimes they were stabbed with fangs and ran several centimetres before immobilized. Portia maintained its orientation, then walked to the stabbed prey and fed. Vision of the prey seemed to be of major importance for most aspects of predatory behaviour. In the rain-forest habitat, webs of Portia, pisaurids, pholcids, and theridiids are often contiguous and facilitate the tactic of web-invasion. It is proposed that the pervasive use of webs by Portia is a primary character conserved from ancestral salticids, and that in the evolution of the family, invasion of contiguous webs could have led to selection for a sophisticated visual system that assisted in the localization of their residents. The developed visual system could then have allowed vagrant predation en route to more distant webs, and finally emancipation from dependence on webs altogether.
A D Blest - One of the best experts on this subject based on the ideXlab platform.
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the biology of Portia fimbriata a web building jumping spider araneae salticidae from queensland utilization of webs and predatory versatility
Journal of Zoology, 2009Co-Authors: Robert R. Jackson, A D BlestAbstract:The biology of a primitive salticid spider, Portia fimbriata (Doleschall), is described from observations in a Queensland rain-forest and the laboratory. Locomotory specializations enable the spiders to move about readily on webs; and all stages of life history are associated with webs, both alien and two types they build themselves. The more flimsy Type 1 webs are used as resting sites similar to the nests employed by more familiar jumping spiders. Type 2 webs are more substantial structures in which the spider moults, mates, oviposits, broods its eggs and remains for as long as 48 days. The predatory strategy of Portia includes the use of distinct alternative tactics in the pursuit of varied types of prey. Most of these tactics are ones not usually associated with salticids. Portia invaded diverse types of webs without difficulty, including adhesive and non-adhesive, cribellate and ecribellate, and two-and three-dimensional ones. Once in the web, Portia produced vibratory stimuli by specialized but varied movements of the legs and palps. Web spiders responded to these in a manner more appropriate for a potential prey item or a conspecific in its web than a potential predator. Sometimes vibrations lured the spider to the waiting Portia. Other times, localized movements were elicited which assisted Portia in remaining orientated toward the spider as it stalked across the web. Outside webs, Portia stalked other species of salticids, moving in a very slow and “mechanical” fashion and arresting forward motion whenever faced by the prey. Evidently, the salticids did not recognize Portia as another salticid and a potential predator. Although Portia pursued insects, they pursued spiders more readily, persistently and successfully. Portia captured insects outside webs, on their own webs and on the webs of other species. Those on their own webs adhered temporarily to the silk. In webs of other spiders, insects were sometimes taken directly from the chelicerae of the host. Also, their own webs assisted Portia in capturing other spiders. Eggs of spiders were fed upon both on and off webs. Different attack tactics tended to be employed with different types of prey: web spiders, lunge; salticids, swoop; insects, pick-up. Egg-cases were opened by means of specialized movements involving the chelicerae and the eggs were raked toward the mouth with the legs. Most prey were seized after the attack, but sometimes they were stabbed with fangs and ran several centimetres before immobilized. Portia maintained its orientation, then walked to the stabbed prey and fed. Vision of the prey seemed to be of major importance for most aspects of predatory behaviour. In the rain-forest habitat, webs of Portia, pisaurids, pholcids, and theridiids are often contiguous and facilitate the tactic of web-invasion. It is proposed that the pervasive use of webs by Portia is a primary character conserved from ancestral salticids, and that in the evolution of the family, invasion of contiguous webs could have led to selection for a sophisticated visual system that assisted in the localization of their residents. The developed visual system could then have allowed vagrant predation en route to more distant webs, and finally emancipation from dependence on webs altogether.
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The biology of Portia fimbriata, a web‐building jumping spider (Araneae, Salticidae) from Queensland: utilization of webs and predatory versatility
Journal of Zoology, 2009Co-Authors: Robert R. Jackson, A D BlestAbstract:The biology of a primitive salticid spider, Portia fimbriata (Doleschall), is described from observations in a Queensland rain-forest and the laboratory. Locomotory specializations enable the spiders to move about readily on webs; and all stages of life history are associated with webs, both alien and two types they build themselves. The more flimsy Type 1 webs are used as resting sites similar to the nests employed by more familiar jumping spiders. Type 2 webs are more substantial structures in which the spider moults, mates, oviposits, broods its eggs and remains for as long as 48 days. The predatory strategy of Portia includes the use of distinct alternative tactics in the pursuit of varied types of prey. Most of these tactics are ones not usually associated with salticids. Portia invaded diverse types of webs without difficulty, including adhesive and non-adhesive, cribellate and ecribellate, and two-and three-dimensional ones. Once in the web, Portia produced vibratory stimuli by specialized but varied movements of the legs and palps. Web spiders responded to these in a manner more appropriate for a potential prey item or a conspecific in its web than a potential predator. Sometimes vibrations lured the spider to the waiting Portia. Other times, localized movements were elicited which assisted Portia in remaining orientated toward the spider as it stalked across the web. Outside webs, Portia stalked other species of salticids, moving in a very slow and “mechanical” fashion and arresting forward motion whenever faced by the prey. Evidently, the salticids did not recognize Portia as another salticid and a potential predator. Although Portia pursued insects, they pursued spiders more readily, persistently and successfully. Portia captured insects outside webs, on their own webs and on the webs of other species. Those on their own webs adhered temporarily to the silk. In webs of other spiders, insects were sometimes taken directly from the chelicerae of the host. Also, their own webs assisted Portia in capturing other spiders. Eggs of spiders were fed upon both on and off webs. Different attack tactics tended to be employed with different types of prey: web spiders, lunge; salticids, swoop; insects, pick-up. Egg-cases were opened by means of specialized movements involving the chelicerae and the eggs were raked toward the mouth with the legs. Most prey were seized after the attack, but sometimes they were stabbed with fangs and ran several centimetres before immobilized. Portia maintained its orientation, then walked to the stabbed prey and fed. Vision of the prey seemed to be of major importance for most aspects of predatory behaviour. In the rain-forest habitat, webs of Portia, pisaurids, pholcids, and theridiids are often contiguous and facilitate the tactic of web-invasion. It is proposed that the pervasive use of webs by Portia is a primary character conserved from ancestral salticids, and that in the evolution of the family, invasion of contiguous webs could have led to selection for a sophisticated visual system that assisted in the localization of their residents. The developed visual system could then have allowed vagrant predation en route to more distant webs, and finally emancipation from dependence on webs altogether.
R. Stimson Wilcox - One of the best experts on this subject based on the ideXlab platform.
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14 – Cognitive Abilities of Araneophagic Jumping Spiders
Animal Cognition in Nature, 1998Co-Authors: R. Stimson Wilcox, Robert R. JacksonAbstract:Publisher Summary This chapter illustrates the cognitive abilities of araneophagic jumping spiders. “Portia,” a genus of araneophagic jumping spiders (family Salticidae), appears to have the most versatile and flexible predatory strategy known for an arthropod. A dominant feature of Portia's predatory strategy is aggressive mimicry, a system in which the predator communicates deceitfully with its prey. Typical salticids do not build webs. Instead, they are hunters that catch their prey in stalk-and-leap sequences guided by vision. Salticids differ from all other spiders by having large anteromedial eyes and acute vision. However, the behavior of Portia is anything but typical for a salticid. Besides hunting its prey cursorily, Portia also builds a prey-catching web. The typical prey of a salticid is insects, but Portia's preferred prey is other spiders. Portia frequently hunts web-building spiders from other families by invading their webs and deceiving them with aggressive-mimicry signals. While in the other spider's web, it makes aggressive-mimicry signals by moving legs, palps, abdomen, or some combination of these to make web-borne vibrations. Portia's typical victim, a web-building spider but not a salticid, typically lacks acute vision and instead perceives the world it lives in by interpreting tension and vibration patterns in its web.
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Spider flexibly chooses aggressive mimicry signals for different prey by trial and error
Behaviour, 1993Co-Authors: Robert R. Jackson, R. Stimson WilcoxAbstract:Portia is a jumping spider that invades other spiders' webs, makes vibratory signals that deceive the resident spider (aggressive mimicry), then attacks and eats the spider. Portia exploits a wide range of prey-spider species. Evidence is provided from observation and experimentation that Portia uses a trial-and-error method as part of its strategy for deriving appropriate signals for different prey. To use this method, Portia first broadcasts an array of different signals, then narrows to particular signals as a consequence of feedback from the prey spider. Feedback can be web vibration or seeing spiders move, or both. This appears to be an example of deception involving at least a limited form of learning, an uncommon phenomenon in invertebrates.
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Observations in nature of detouring behaviour by Portia fimbriata, a web‐invading aggressive mimic jumping spider from Queensland
Journal of Zoology, 1993Co-Authors: Robert R. Jackson, R. Stimson WilcoxAbstract:Portia fimbriata, a web-invading, araneophagic salticid that uses aggressive mimicry to deceive its prey (web-building spiders), takes indirect routes to reach its prey (i.e. it makes detours). Data are presented from 18 instances of Portia making detours to reach prey in nature, the prey being five different species of web-building spiders. Portia spent 17 min (median) per predatory sequence with the prey out of view and covered 375 mm detouringper sequence. These detours were longer and more complex than those previously recorded for salticids, and these are the first detailed records of detouring behaviour by a salticid in the field.
Duane P. Harland - One of the best experts on this subject based on the ideXlab platform.
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Prey classification by Portia fimbriata, a salticid spider that specializes at preying on other salticids: species that elicit cryptic stalking
Journal of Zoology, 2006Co-Authors: Duane P. Harland, Robert R. JacksonAbstract:Portia fimbriata from Queensland, Australia, is an araneophagic jumping spider (Salticidae) that includes in its predatory strategy a tactic (cryptic stalking) enabling it to prey effectively on common sympatric salticids from other genera. Using standardized tests in which only optical cues were available (prey enclosed in small glass vial within large cage), the reactions of P. fimbriata to 114 salticid species were investigated. Except for Myrmarachne spp. (ant mimics), all salticids tested triggered cryptic stalking by P. fimbriata. This included not only sympatric, but also allopatric, salticids. The salticid on which P. fimbriata most commonly preys in nature is Jacksonoides queenslandicus, but cryptic stalking was triggered by salticid species with considerably different appearances, including beetle mimics, species with unusual body shapes and species with a wide variety of camouflaging markings. Portia fimbriata was also tested with lycosid, clubionid, theridiid and desid spiders and with flies and ants, but none of these arthropods triggered cryptic stalking. Optical cues used by P. fimbriata for discrimination between salticid and non-salticid prey are discussed.
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A knife in the back: use of prey-specific attack tactics by araneophagic jumping spiders (Araneae: Salticidae)
Journal of Zoology, 2006Co-Authors: Duane P. Harland, Robert R. JacksonAbstract:Three species of Portia (Portia africana from Kenya, Portia fimbriata from Australia and Portia labiata from the Philippines) were tested with flies Drosophila immigrans and Musca domestica and with web-building spiders Badumna longinquus and Pholcus phalangioides. Badumna longinquus has powerful chelicerae, but not especially long legs, whereas Ph. phalangioides has exceptionally long legs, but only small, weak chelicerae. Typically, Portia sighted flies, walked directly towards them and attacked without adjusting orientation. However, Portia’s attacks on the spiders were aimed primarily at the cephalothorax instead of the legs or abdomen. Portia usually targeted the posterior-dorsal region of B. longinquus’ cephalothorax by attacking this species from above and behind. When the prey was Ph. phalangioides, attack orientation was defined primarily by opportunistic gaps between this species’ long legs (gaps through which Portia could contact the pholcid’s body without contacting one of the pholcid’s legs). Portia’s attack strategy appears to be an adjustment to the different types of risk posed by different types of prey.
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behavioural and cognitive influences of kairomones on an araneophagic jumping spider
Behaviour, 2002Co-Authors: Robert R. Jackson, Robert J. Clark, Duane P. HarlandAbstract:In laboratory experiments, Portia fimbriata, an araneophagic salticid from Queensland, was influenced by olfactory and contact-chemical cues from Jacksonoides queenslandicus, an abundant salticid on which P.fimbriata preys. Four distinct effects were revealed: P.fimbriata (1) moved into and remained in the vicinity of J. queenslandicus, (2) performed undirected leaping, behaviour known to function as speculative hunting by inducing a turning response from not-yet-seen J. queenslandicus, (3) adopted a posture (retracted palps) known to be routine when stalking salticids and (4) showed enhanced attention to optical cues from J. queenslandicus. Laboratory experiments provided no statistical evidence that chemical cues from other prey species affected P.fimbriata, that J. queenslandicus was affected by chemical cues from P. fimbriata or that allopatric Portia were sensitive to chemical cues from J. queenslandicus.
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Distances at which jumping spiders (Araneae: Salticidae) distinguish between prey and conspecific rivals
Journal of Zoology, 1999Co-Authors: Duane P. Harland, Robert R. Jackson, Aynsley M. MacnabAbstract:Distances at which jumping spiders (Salticidae) use optical cues to distinguish between prey insects and conspecific rivals were investigated using adult males of 37 species. During tests, salticids walked up a ramp toward a mirror or toward an insect enclosed in a transparent petri dish. All species directed threat displays toward their own mirror images and the displays were comparable to each species' typical behaviour during male–male interactions. The salticids never displayed in tests with insects at the top of the ramp. The virtual distances at which the spiders displayed are interpreted as an indication of the distances at which each species can distinguish rivals from prey. Representative species were from the subfamilies Lyssomaninae, Spartaeinae and Salticinae. Discrimination distances relate well to the foveal layer I receptor mosaics of the anterior median eyes for the three subfamilies. Compared with the salticines, the lyssomanines and, except for Portia, the spartaeines tended to have shorter discrimination distances. Portia spp. had discrimination distances comparable to the longest recorded for the salticines. The longest discrimination distances found were for the salticine Mogrus neglectus (max. 320 mm or 42 body lengths) and for the spartaeine Portia fimbriata (280 mm or 47 body lengths).
Michael S. Tarsitano - One of the best experts on this subject based on the ideXlab platform.
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Route selection by a jumping spider (Portia labiata) during the locomotory phase of a detour
Animal Behaviour, 2006Co-Authors: Michael S. TarsitanoAbstract:The jumping spider Portia labiata can complete detours in which it must move away from a goal (i.e. prey) before approaching it. This detouring behaviour can be divided into two phases: a scanning phase, during which Portia stays roughly in one spot and examines its environment using its principal eyes, and a locomotory phase, during which Portia performs the detour. Earlier experiments showed that when Portia is initially confined to a small, elevated platform from which it has an unobstructed view of the goal, it plans the initial stage of its detour by scanning the possible route and picking out an unbroken path from start to goal and then aiming at an initial objective along the detour. In the present experiments, I examined the detouring behaviour of P. labiata in an open arena where obstacles provided either indirect access or no access to the goal. Although scanning movements and detour decisions of spiders were similar to those of spiders initially confined to an elevated platform, spiders in the open arena not only scanned at the start but also along the route of the detour. Decision making thus occurred gradually, during both the scanning and the locomotory phases. Taken together, these results and those of previous studies suggest that detouring behaviour in Portia involves a form of vicarious trial and error in which the spider inspects possible routes and selects a series of intermediate goals during both the scanning and locomotory phases of a detour.
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Scanning and route selection in the jumping spider Portia labiata.
Animal behaviour, 1999Co-Authors: Michael S. Tarsitano, Richard J. AndrewAbstract:Abstract Jumping spiders Portia labiata were tested in the laboratory on three different kinds of detours. In one, both routes led to the lure. In the other variants, one of the routes had a gap, making that route impassable. When tested with only one complete route, Portia chose this route after visually inspecting both routes. An analysis of scanning showed that, at the beginning of the scanning routine, the spiders scanned both the complete and the incomplete route but that, by the end of the scanning routine, they predominantly scanned only the complete route. Two rules seemed to govern their scanning: (1) they would continue turning in one direction when scanning away from the lure along horizontal features of the detour route; and (2) when the end of the horizontal feature being scanned was reached, they would change direction and turn back towards the lure. These rules ‘channelled’ the spiders' scanning on to the complete route, and they then overwhelmingly chose to head towards the route they had fixated most while scanning.
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Influence of Prey Movement On the Performance of Simple Detours By Jumping Spiders
Behaviour, 1992Co-Authors: Michael S. Tarsitano, Robert R. JacksonAbstract:The influence of prey movement on the performance of simple detours by salticids was investigated. Seven species were studied. Two subject species, Portia fimbriata and Portia labiata, are specialized web-invading species that eat other spiders. The other five species investigated (Euryattus sp., Euophrys parvula, Marpissa marina, Trite auricoma and Trite planiceps) are more typical cursorial hunters of insects. We provide evidence that: 1) salticids will initiate detours toward motionless prey; 2) salticids are more inclined to initiate detours toward moving than toward motionless prey; 3) salticids tend to complete detours even when prey that had been moving at the start remains stationary during the detour; 4) prey movement makes the salticid more likely to stalk and attack when prey is only a few centimetres away and in a position from which it can be reached by a straightline pursuit; 5) Portia is more inclined than the other salticids to initiate detours to motionless prey, then to stalk and attack motionless prey when close, than the other salticids are. Mechanisms that might account for Portia being different from the other salticids are discussed.
