Behavioral Ecology
doi:10.1093/beheco/ark003
Advance Access publication 28 April 2006
Burrow decorations as antipredatory devices
Jennifer L. Williams,a,b Jordi Moya-Laraño,a,c and David H. Wisea
Department of Entomology, S-225 Agricultural Science Building-North, University of Kentucky,
Lexington, KY 40546-0091, USA, bDepartment of Entomology, University of Arizona, Forbes 410,
PO Box 2100: (36), Tucson, AZ 85721-003, USA, and cEstación Experimental de Zonas Áridas,
CSIC, General Segura 1, Almerı́a 04001, Spain
a
nimal decorations are usually thought to function as signals of quality (e.g., Andersson 1994; Soler et al. 1998;
Madden 2002). However, web decorations are widespread
among araneoid spiders (Herberstein et al. 2000). A recent
hypothesis proposes that in this group these decorations can
function as devices to attract prey (e.g., Craig and Bernard
1990; Craig et al. 2001). Recent evidence suggests, however,
that rather than attracting prey these devices make spider silk
cryptic to prey, thereby increasing the chances that flying
insects are intercepted by the web (Blackledge and Wenzel
2000). Older hypotheses suggest that in some clades decorations could also serve an antipredatory function (Hingston
1927; Schoener and Spiller 1992; Blackledge 1998). Among
these hypotheses, the one that enjoys the strongest empirical
support is that which states that web decorations prevent predators from detecting the spider in the center of the web
(Blackledge and Wenzel 2001; Eberhard 2003; Chou et al.
2005). However, other studies have failed to support this hypothesis (Herberstein et al. 2000; Craig et al. 2001). Some
visually hunting spider predators may actually use the decorations as cues to locate the spiders (Bruce et al. 2001; Seah and
Li 2001).
Our understanding of the antipredatory function of decorations will benefit from including other systems. Lycosa tarantula
(L.), the Mediterranean tarantula, and its predator Buthus
occitanus (Amoreux), the Occitan scorpion, are native to the
same desert areas and are found in expansive, flat, and welldrained soils (Moya-Laraño 1999). Both species live in burrows, although B. occitanus tends to build its burrows under
stones more often than L. tarantula (J Moya-Laraño, personal
observations). Some species of burrowing wolf spiders construct a turret around their burrow, which is a small collarlike
structure made from twigs, pebbles, and other debris. The
debris is fastened together with silk (Wallace 1942; Shook
1978; Ortega 1986). Individuals of L. tarantula almost invariably build a turret around their burrows (Figure 1). Shook
A
Address correspondence to J. Moya-Laraño. E-mail: jordi@eeza.
csic.es.
Received 23 October 2005; revised 8 March 2006; accepted 10
March 2006.
The Author 2006. Published by Oxford University Press on behalf of
the International Society for Behavioral Ecology. All rights reserved.
For permissions, please e-mail: [email protected]
(1978) proposed that the turret may function as an early-warning
mechanism such that the spider located inside the burrow
would be able to detect a disturbance caused by either predator or prey via vibrations conducted through strands of silk
connecting the ground to the turret and the turret to the
spider. Shook (1978) suggested that the turret could serve
as a high place from which the spider could visually detect
prey from longer distances. Several similar devices that spiders
use to locate prey have been documented (Barth 2002). Ortega
(1986) hypothesized that the turret may signal the location
of the burrow to the spider, allowing it to locate and reenter
the burrow as quickly as possible. The early-warning hypothesis predicts that when exposed to predators, spiders with no
turret will have a higher chance of being preyed on. The
natural rate of burrow invasion of female L. tarantula burrows
by B. occitanus can be as high as 22% (Moya-Laraño, Pascual,
et al. 2003). Invasion may actually end in predation of the
spider by the scorpion, although the spider usually escapes
and can be found wandering in the vicinity of the burrow
(Moya-Laraño 1999). The fact that spiders can escape predation is consistent with the existence of an early-warning mechanism. We tested this hypothesis for the antipredatory
function of burrow decorations in the Mediterranean tarantula and also investigated a second hypothesis, that the turret
camouflages the burrow from predators.
MATERIALS AND METHODS
Field site and species
This study was conducted in a desert grassland population in
Cabo de Gata, Almerı́a, Spain. Characteristics of the field
site can be found elsewhere (Moya-Laraño et al. 1998; MoyaLaraño 1999; Moya-Laraño et al. 2002).
The Mediterranean tarantula is a nocturnal, cannibalistic,
and territorial burrowing wolf spider (Fernández-Montraveta
and Ortega 1990; Fernández-Montraveta et al. 1991; Ortega
et al. 1992; Moya-Laraño et al. 1996, 2002). Adult females fight
over both burrows (Fernández-Montraveta and Ortega 1990;
Fernández-Montraveta et al. 1991) and territories (MoyaLaraño et al. 2002), suggesting that these are limiting resources
for L. tarantula. Buthus occitanus is also nocturnal and a sit-andwait predator, which, like L. tarantula, actively hunts around
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Animal decorations are normally interpreted as signals of quality. In spiders, however, decorations may have different functions,
including the attraction of prey to the web or making the spider cryptic to predators. To date, there is scant evidence for the latter
hypothesis. Here we use the burrow-decorating wolf spider Lycosa tarantula to test whether turrets around the burrow serve to
prevent burrow invasion and predation from the Occitan scorpion Buthus occitanus. We located spiders and scorpions in field
enclosures and manipulated the presence or absence of decorations or turrets. We found that the presence of the turret
decreases the rate of burrow invasion and improves spider survival, possibly because the turret makes the burrow cryptic to
scorpions. In addition, a field survey showed that burrows with larger decorations had a lower chance of being invaded by
scorpions. These results provide evidence that the decoration has an antipredatory function in nature. Key words: antipredatory
mechanisms, burrowing wolf spiders, coexistence, decorations, intraguild predation, Scorpiones. [Behav Ecol 17:586–590 (2006)]
Williams et al.
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Burrow decorations as antipredatory devices
587
Experiment 1: do burrow decorations warn the spider of
invasion by a scorpion?
the burrow (Skutelsky 1995, 1996). In addition to using tactile
cues to locate prey (Polis 1990), B. occitanus can utilize olfactory
cues of the prey (Krapf 1986).
Overview of the study
Experiment 1 tested the early-warning hypothesis (Shook
1978). We recorded the relocation of the spiders and scorpions and the death rate of spiders to assess the consequences
of removing the turret. Experiment 2 tested the hypothesis
that the turret serves a cryptic function and was designed and
executed after the results of Experiment 1 were known. Only
adult female spiders were used. In both experiments, burrows
occupied by a spider were first located, and then each individual burrow was surrounded with an aluminum fence
(0.75 m [diameter] 3 0.20 m [height], inserted 2 cm into
the ground, with any loose soil packed tightly against the base
to prevent immigration or emigration of spider or scorpion).
Neither adult female L. tarantula nor B. occitanus can climb
smooth metallic surfaces (J Moya-Laraño, personal observation). The turret on top of the burrow was either left intact
or removed, and a scorpion was either present or absent. Inside every enclosure, a small (ca. 25 cm in diameter), flat rock
was placed due east of the burrow. The scorpion was then
placed nearby the rock within the enclosure. Because this procedure took place during the day, when scorpions are inactive,
the scorpions immediately went underneath the rock. Rocks
were placed within each enclosure in each treatment.
Each spider, burrow, and scorpion was used only once during the entire study. To ensure that predation was unidirectional, that is, scorpion on spider, scorpions larger than 4 cm
(prosoma 1 mesosoma) were used. Adult female L. tarantula
are almost always smaller than 4 cm. Scorpions larger than
4 cm have been observed feeding on female L. tarantula, but
spiders have never been observed feeding on adult scorpions
of this size. Scorpions were collected about 0.5 km from the
survey area and introduced into the enclosures immediately
after capture. At the end of both experiments, an attempt was
made to extract the spiders to determine if the burrows were
occupied (see Moya-Laraño et al. 1996).
We also conducted a survey of undisturbed burrows and
measured the size of their decorations in order to determine
if turret size is correlated with the rate of invasion by scorpions. The study took place from June to August 1999, which
overlaps with the breeding season of L. tarantula.
Experiment 2: do decorations make the burrows cryptic to
scorpions?
The results of Experiment 1 suggested that indeed the turret
aids in avoiding predation from scorpions but that the mechanism is different than that suggested by the early-warning
hypothesis. An alternative explanation is that the turret renders the burrow cryptic to scorpions, thereby increasing the
probability of spider survival by decreasing the probability that
the scorpion locates the burrow and preys on the spider.
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Figure 1
Female Lycosa tarantula beside her burrow. Note the conspicuous
burrow decoration at the entrance.
We randomly assigned 40 spiders to 1 of 4 treatments (10
replicates per treatment): turret present with scorpion (T–S),
turret absent with scorpion (NT–S), turret present without
scorpion (T–NS), and turret absent without scorpion (NT–
NS). The turret was removed by gently squeezing it and pulling it out and away from the burrow opening. We predicted,
in accordance with the early-warning hypothesis, that eliminating the turret would increase the probability that the scorpion would kill the spider and that spiders in burrows with
a turret would show a higher rate of burrow abandonment,
with the scorpion taking over the burrow and the spider relocating under the rock. Because predation rate was assessed
as the number of spiders that were absent 24 h after scorpions
were introduced into the enclosure, it was necessary to establish controls for other unknown sources of predation during
that period. For example, Dupont’s Lark, Chersophilus duponti
(Vieillot), is an important predator of L. tarantula (Herranz
et al. 1993); it has been suggested that their relatively long
bill could be an adaptation to reach spiders in the burrow
(X Parellada, personal communication). The red fox (Vulpes
vulpes L.) is also a major predator of L. tarantula (e.g., MoyaLaraño 2002; Moya-Laraño et al. 2002). The absence of the
turret alone could facilitate the access of predators to the
spiders. Thus, to control for the effect of unknown predation
and for the effect of the presence or absence of the turret on
these other potential sources of predation, we established the
2 control treatments in which scorpions were not present
(T–NS and NT–NS). If the turret had no effect on predation by
species other than scorpions, the rate of spider disappearance
would be equal in both control treatments (T–NS vs. NT–NS).
If the turret protected spiders from predation by scorpions,
the rate of disappearance in the treatment with both scorpion
and turret (T–S) would not differ from that of the 2 control
treatments. Consequently, we predicted that spider disappearance in the treatment with scorpion but without a turret
would be higher than in the other 3 treatments. We predicted
that in the absence of predator disturbance, relocation rate of
the spiders would be the same in both control treatments
(T–NS vs. NT–NS). Relocation in the treatment with both a
turret and a scorpion would be higher than in the controls,
indicating that, as predicted by the early-warning hypothesis,
the spiders were able to detect the scorpion approaching the
burrow and escape predation. No predictions were made for
differences in the rate of relocation between the treatment
with scorpion without a turret (NT–S) relative to other treatments. Because we did not expect the scorpion and spider to
be found together alive inside the burrow, we measured the
rate of spider relocation from the point of view of the scorpion
independently of whether the spider was dead or somewhere
else within the enclosure. Consequently, relocation rate was
defined as the rate of burrow invasion by scorpions. All predictions were tested using Williams-corrected G-tests (Sokal
and Rohlf 1995) on planned comparisons (Rosenthal and
Rosnow 1985).
Behavioral Ecology
588
Survey: does size of the burrow decoration determine the
rate of invasion by scorpions?
The results of Experiments 1 and 2 suggested that the turret
prevents scorpion invasion. However, invaded burrows in nature almost invariably have a turret (Moya-Laraño 1999; MoyaLaraño, Pascual, et al. 2003). A possible explanation for this
difference between the results of the experiments and the
pattern in nature (other than the fact that the experiments
were of short duration) is that although burrows with turrets
are eventually invaded, higher turrets, which have more decorations, would be more efficient at camouflaging the burrow
from scorpions. Females use debris and surrounding vegetation to build their turrets, so the amount of vegetation around
the burrow could influence turret height. Burrow sites with
more vegetation would then be less susceptible to scorpion
invasion. Alternatively, dense vegetation cover could make the
burrow less susceptible to scorpion invasion solely because
scorpions may not be able to move efficiently through the
vegetation and would tend to avoid such areas. A survey was
conducted to determine whether turret height and/or vegetation height were correlated with the rate of scorpion
invasion.
We located 118 burrows and measured the turret height
and the height of the surrounding vegetation. Burrows were
used only if they contained an adult female spider. All burrows
were marked individually with a numbered flag inserted into
the ground beside each burrow. Turret height was determined
as the average of measurements taken at 4 equidistant points.
Three measurements of vegetation height were taken at 5, 10,
and 15 cm radially outward from each measurement point on
the turret. Vegetation height was the average of these 12 measurements. After a week, the burrows were examined for the
presence of a scorpion. Results were analyzed using multiple
logistic regression (Allison 1999).
Figure 2
Logistic regression of field data showing a decrease in the probability of burrow invasion by scorpions with an increase in decoration
(turret) height (statistical analyses in the text; N ¼ 118 burrows).
treatments (0/10 [T–NS] vs. 0/10 [NT–NS], G1 ¼ 0, P ¼ 1),
and, contrary to the early-warning hypothesis, the relocation
rate (scorpion invasion rate) in the treatment with both scorpion and turret was also zero (0/20 [T–NS 1 NT–NS] vs. 0/10
[T–S], G1 ¼ 0, P ¼ 1). However, the treatment with a scorpion
and no turret had an unexpectedly high rate (90%) of scorpion invasion (9/10 [NT–S] vs. 0/30 [T–NS 1 NT–NS 1 T–S],
G1 ¼ 33.3, P , 0.0001).
Experiment 2: do decorations alone make the burrows
cryptic to scorpions?
The scorpion invasion rate was zero in both treatments (0/10
[spider] vs. 0/10 [no-spider], G1 ¼ 0, P ¼ 1), indicating that
the turret alone was sufficient to prevent the scorpion from
invading the burrow.
Survey: does size of the burrow decoration determine the
rate of invasion by scorpions?
Eight burrows (ca. 7%) were found to have been invaded by
scorpions. The larger the decoration (the higher the turret),
the smaller was the probability of scorpion invasion (Figure
2). Spiders inhabiting areas with taller vegetation built burrows with taller decorations (R2 ¼ 0.225; F1,116 ¼ 33.7; P ,
0.0001; Figure 3). When we included both vegetation height
and turret height in a multiple logistic regression, only turret
height (controlling for vegetation height) explained scorpion
invasion rate (logistic regression: decoration height, v21 ¼ 4.8,
P ¼ 0.028; vegetation height, v21 ¼ 1.1, P ¼ 0.294).
RESULTS
Experiment 1: do burrow decorations warn the spider of
invasion by a scorpion?
Removing the turret increased spider mortality from scorpion
predation. The death rate was zero in both control treatments
(0/10 [T–NS] vs. 0/10 [NT–NS], G1 ¼ 0, P ¼ 1) and in the
treatment with both a scorpion and turret (0/20 [T–NS 1
NT–NS] vs. 0/10 [T–S], G1 ¼ 0, P ¼ 1), indicating that there
were no sources of spider mortality in the experiment other
than scorpions. The death rate in the NT–S treatment was
20%, which was significantly higher than in the other treatments (0/30 [T–NS 1 NT–NS 1 T–S] vs. 2/10 [NT–S], G1 ¼
4.31, P ¼ 0.038). The relocation rate was zero in both control
DISCUSSION
Our first field experiment demonstrated that burrow decorations serve an antipredatory function for L. tarantula. Mortality of spiders in burrows from which the turret had been
removed was 20%, which was due entirely to scorpion predation because mortality was zero in all other treatments. However, the early-warning hypothesis (Shook 1978) for the
function of the turret was not supported because relocation
was 90% higher in the burrows with scorpion and no turret
than in the burrows with scorpion and turret. Results from
Experiment 1 were more consistent with the hypothesis that
the turret makes the burrow cryptic to scorpions. Experiment 2
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An alternate explanation is that spiders may prevent scorpions
from invading the burrow or escape scorpion predation more
efficiently if they have a turret than if they lack such device. By
occupying a more elevated position than the attacking scorpion (i.e., on top of the turret), spiders could fight the scorpions more efficiently or be more adept at avoiding the
scorpion sting. To distinguish between the latter 2 hypotheses,
we conducted Experiment 2.
In this experiment, the field procedures, other than the
treatments themselves, were identical to Experiment 1. We
established 2 treatments of 10 replicates each: scorpion with
a spider and scorpion without a spider. The turrets on top of
burrows were left intact. If the presence of the spider did not
affect the probability of scorpion invasion, then the hypothesis that the turret alone makes the burrow cryptic to scorpions
would be supported.
Williams et al.
•
Burrow decorations as antipredatory devices
589
1998; Herberstein et al. 2000; Craig et al. 2001). We have
found evidence that the turret of the burrow of the Mediterranean tarantula functions to reduce invasion by the Occitan
scorpion. By reducing mortality from scorpion predation, this
decoration likely contributes to the coexistence of the 2 largest arthropod predators in the community. This is therefore
a new system that contributes further to our understanding on
the functioning of animal decorations.
Figure 3
Positive correlation between vegetation height and the height of
burrow decorations (turrets) (see the text for statistical analysis;
N ¼ 118 burrows).
demonstrated that the turret alone is sufficient to camouflage
the burrow from scorpions. In addition, a field survey showed
that the burrows with smaller turrets were more susceptible to
scorpion invasion, supporting the hypothesis that, in nature,
larger decorations make the burrow more cryptic to scorpions.
The turret could camouflage the burrow from scorpions by
masking visual, tactile, or olfactory cues. The hypothesis of
tactile camouflage is consistent with the fact that most scorpions cannot see very well and rely heavily on tactile cues
(Polis 1990). The debris and vegetation used to build the
turret might make the burrow appear like the surrounding
vegetation to the scorpion. However, because B. occitanus
can rely on olfactory cues to locate prey (Krapf 1986), it is
also possible that the scorpion could smell L. tarantula and
that the turret somehow also camouflages the spider’s odor.
Visual cues are likely to be of minor importance (Polis 1990),
but if the scorpion were to rely somewhat on sight to find the
spider, it could be possible that the turret, being similar to the
surrounding vegetation, visually camouflages the spider. At
this point, we are not able to distinguish which cues were
responsible for the camouflage.
Although the amount of vegetation partially determined
decoration size, the height of the turret, independently of
vegetation height, was the only factor that explained the scorpion invasion rate. This pattern suggests that spider effort in
turret construction, in excess of the available vegetation, is
a factor determining whether or not spiders escape scorpion
predation. The rate of burrow invasion by scorpions and the
food availability in the microhabitat may influence the spider’s investment in the turret. Body condition is known to
affect burrow decorations: in the laboratory, juvenile spiders
supplied with additional food build higher turrets (J MoyaLaraño, unpublished data). Field evidence suggests that males
actively choose to mate with well-fed females (Moya-Laraño,
Pascual, et al. 2003; Moya-Laraño, Orta-Ocaña, et al. 2003). In
addition to other female traits (Moya-Laraño, Taylor, et al.
2003), decorations might also be used by males to assess
female quality because female spiders with larger decorations would exhibit lower rates of mortality from scorpion
predation.
One of the hypotheses for the evolution and maintenance
of spider decorations is that decorations evolved and are
maintained because they reduce mortality from predation
(Hingston 1927; Schoener and Spiller 1992; Blackledge
REFERENCES
Allison PD. 1999. Logistic regression using the SAS system. Cary, NC:
SAS Institute Inc.
Andersson M. 1994. Sexual selection. Princeton, NJ: Princeton University Press.
Barth FG. 2002. A spider’s world—senses and behavior. Heidelberg,
Germany: Springer Verlag.
Blackledge TA. 1998. Signal conflict in spider webs driven by predators and prey. Proc R Soc Lond B Biol Sci 265:1991–6.
Blackledge TA, Wenzel JW. 2000. The evolution of cryptic spider silk:
a behavioral test. Behav Ecol 11:142–5.
Blackledge TA, Wenzel JW. 2001. Silk mediated defense by an orb
web spider against predatory mud-dauber wasp. Behaviour 138:
155–71.
Bruce MJ, Herberstein ME, Elgar MA. 2001. Signalling conflict between prey and predator attraction. J Evol Biol 14:786–94.
Chou IC, Wang PH, Shen PS, Tso IM. 2005. A test of prey attracting
and predator defence functions of prey carcass decorations built by
Cyclosa spiders. Anim Behav 69:1055–66.
Craig CL, Bernard GD. 1990. Insect attraction to ultraviolet-reflecting
spider webs and web decorations. Ecology 71:616–23.
Craig CL, Wolf SG, Davis JLD, Hauber ME, Maas JL. 2001. Signal
polymorphism in the web-decorating spider Argiope argentata is correlated with reduced survivorship and the presence of stingless
bees, its primary prey. Evolution 55:986–93.
Eberhard WG. 2003. Substitution of silk stabilimenta for egg sacs by
Allocyclosa bifurca (Araneae: Araneidae) suggests that silk stabilimenta function as camouflage devices. Behaviour 140:847–68.
Fernández-Montraveta C, Lahoz-Beltra R, Ortega J. 1991. Spatial distribution of Lycosa tarentula fasciiventris (Araneae, Lycosida) in a population from Central Spain. J Arachnol 19:73–9.
Fernández-Montraveta C, Ortega J. 1990. El comportamiento agonı́stico de hembras adultas de Lycosa tarentula fasciiventris (Araneae,
Lycosidae). J Arachnol 18:49–58.
Herberstein ME, Craig CL, Coddington JA, Elgar MA. 2000. The functional significance of silk decorations of orb-web spiders: a critical
review of the empirical evidence. Biol Rev 75:649–69.
Herranz J, Yanes M, Suárez F. 1993. Primeros datos sobre la dieta de
pollos de alondra de Dupont, Chersophilus duponti, en la Penı́nsula
Ibérica. Ardeola 40:77–9.
Hingston RWG. 1927. Protective devices in spider’s snares, with a description of seven new species of orb-weaving spiders. Proc R Soc
Lond B Biol Sci 28:259–93.
Krapf D. 1986. Contact chemoreception of prey in hunting scorpions
(Arachnida: Scorpiones). Zool Anz 217:119–29.
Madden JR. 2002. Bower decorations attract females but provoke
other male spotted bowerbirds: bower owners resolve this tradeoff. Proc R Soc Lond B Biol Sci 269:1347–51.
Moya-Laraño J. 1999. Limitación por el alimento, territorialidad y
canibalismo en la tarantula Mediterranea, Lycosa tarentula (L.)
(Araneae: Lycosidae) [PhD dissertation]. Barcelona, Spain: Universidad Autònoma de Barcelona.
Downloaded from http://beheco.oxfordjournals.org/ at Pennsylvania State University on February 27, 2014
We thank X. Parellada for letting us to publish the picture of the
female and the turret. The administration of the Cabo de Gata-Nı́jar
Natural Park issued a permit to work within the park. The Michelin
group kindly allowed us to work on its property. J.M.-L. was supported
by a scholarship from the Ministerio de Educación y Cultura of the
Spanish Government (AP95 33906935). The manuscript has been
partially written under a grant from the Spanish Ministry of Education
(CGL2004-03153/BOS) to J.M.-L. and D.H.W. J.L.W. was partially supported by the University of Kentucky Undergraduate Creativity Grant
and a Sigma Xi Grant in Aid of Research.
590
Polis GA. 1990. The biology of scorpions. Stanford, CA: Stanford University Press.
Rosenthal R, Rosnow RL. 1985. Contrast analysis: focused comparisons in the analysis of variance. New York, NY: Cambridge University
Press.
Schoener TW, Spiller DA. 1992. Stabilimenta characteristics of the
spider Argiope argentata on small islands: support of the predator
defense hypothesis. Behav Ecol Sociobiol 31:309–18.
Seah WK, Li D. 2001. Stabilimenta attract unwelcome predators to
orb-webs. Proc R Soc Lond B Biol Sci 268:1553–8.
Shook SS. 1978. Ecology of the wolf spider, Lycosa carolinensis
Walckenaer (Araneae: Lycosidae) in a desert community. J Arachnol
19:73–9.
Skutelsky O. 1995. Flexibility in foraging tactics of Buthus occitanus
scorpions as a response to above-ground activity of termites. J Arachnol
23:44–5.
Skutelsky O. 1996. Predation risk and state dependent foraging in
scorpions: effects of foraging in the scorpion Buthus occitanus. Anim
Behav 52:49–57.
Sokal RR, Rohlf FJ. 1995. Biometry. New York: Freeman.
Soler JJ, Moller AP, Soler M. 1998. Nest building, sexual selection and
parental investment. Evol Ecol 12:427–41.
Wallace HK. 1942. A revision of the burrowing wolf spiders of
the genus Geolycosa (Araneae: Lycosidae). Am Midl Nat 27:
1–62.
Downloaded from http://beheco.oxfordjournals.org/ at Pennsylvania State University on February 27, 2014
Moya-Laraño J. 2002. Senescence and food limitation in a slowly ageing spider. Funct Ecol 16:734–41.
Moya-Laraño J, Orta-Ocaña JM, Barrientos JA, Bach C, Wise DH. 1998.
Limitación por la comida en las arañas del Cabo de Gata. Investig
Gest Med Nat 3:73–7.
Moya-Laraño J, Orta-Ocaña JM, Barrientos JA, Bach C, Wise DH. 2002.
Territoriality in a cannibalistic burrowing wolf spider. Ecology
83:356–61.
Moya-Laraño J, Orta-Ocaña JM, Barrientos JA, Bach C, Wise DH. 2003.
Intriguing compensation by adult female spiders for food limitation
experienced as juveniles. Oikos 101:539–48.
Moya-Laraño J, Orta-Ocaña JM, Barrientos JA, Cases A. 1996. Dynamics of a population of burrowing wolf spiders. Is there any competition? Rev Suisse Zool Vol Hors Sér:491–9.
Moya-Laraño J, Pascual J, Wise DH. 2003. Mating patterns in
late-maturing Mediterranean tarantulas may reflect the costs and
benefits of sexual cannibalism. Anim Behav 66:469–76.
Moya-Laraño J, Taylor PW, Fernández-Montraveta C. 2003. Body patterns as potential amplifiers of size and condition in a territorial
spider. Biol J Linn Soc 78:355–64.
Ortega J. 1986. Posibles relaciones entre el hábitat de Lycosa fasciiventris (Dufour) (Araneae, Lycosidae) y su comportamiento. Bol R Soc
Esp Hist Nat 82:121–9.
Ortega J, Ruiz M, Fernández-Montraveta C. 1992. Daily patterns of locomotor activity in a Lycosid Spider. J Interdiscip Cycle Res 23:295–301.
Behavioral Ecology