Influence of predation risk and plant
structure on vigilance and intermittent
locomotion in Microcavia australis
(Rodentia, Caviidae)
acta ethologica
ISSN 0873-9749
Volume 14
Number 1
acta ethol (2011) 14:27-33
DOI 10.1007/
s10211-010-0087-0
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acta ethol (2011) 14:27–33
DOI 10.1007/s10211-010-0087-0
ORIGINAL PAPER
Influence of predation risk and plant structure
on vigilance and intermittent locomotion
in Microcavia australis (Rodentia, Caviidae)
Paula Taraborelli & Pablo Moreno & Ana Srur &
Carolina Carballido & Stella M. Giannoni
Received: 30 April 2009 / Revised: 10 June 2010 / Accepted: 3 November 2010 / Published online: 14 December 2010
# Springer-Verlag and ISPA 2010
Abstract The aim of this study was to analyze and compare
vigilance behavior and intermittent locomotion at two sites (El
Leoncito and Ñacuñán, Argentina) that differ in predation
risk, plant structure, and plant resource availability. Subjects
were lesser cavies (Microcavia australis), a social species
that is semi-fossorial, diurnal, and native to South America.
Continuous focal sampling was conducted during the day, at
times of food shortage, food abundance, and reproduction
from 2003 to 2005. The proportion of time spent vigilance
was significantly higher at Ñacuñán, where vigilance peaked
at midday and reached a minimum in the evening. This
midday peak of vigilance at Ñacuñán was associated with a
midday peak of danger from raptors as indicated by a raptor
activity peak at that time. In contrast, both vigilance and
predator activity at El Leoncito were constant through the
day. Records of intermittent locomotion and number and
duration of pauses in locomotion were significantly higher at
P. Taraborelli (*) : P. Moreno
Grupo de Investigaciones de la Biodiversidad, Instituto Argentino
de Investigaciones de Zonas Áridas, CCT, CONICET,
Av. Ruiz Leal s/n, Parque General San Martín, CC 507,
CP 5500, Mendoza, Argentina
e-mail: [email protected]
S. M. Giannoni
Instituto y Museo de Ciencias Naturales,
Universidad Nacional de San Juan,
Av. España 400 Norte,
San Juan, Argentina CP 5400
A. Srur
Dendrocronología-IANIGLA-CCT, CONICET,
Mendoza, Argentina CP 5500
C. Carballido
Facultad de Ciencias Exactas y Naturales, UBA,
Buenos Aires, Argentina C1428EGA
El Leoncito, a difference that may have been due to the need
for greater vigilance while moving across areas of less
protective cover at this site.
Keywords Vigilance . Intermittent locomotion . Plant
structure . Predation risk . Microcavia australis
Introduction
Several aspects of rodent behavior and ecology support an
inverse relationship between the amount of plant cover and
predatory risk (Ebensperger 2001). Predation risk increases
significantly in open areas (Lima 1987). Other authors
support that an increase in the rate of predator attacks
results in an increase in vigilance levels (Lima 1987; Elgar
1989; Sundell and Ylönen 2004). Vigilance is a behavior
that enhances the likelihood that an animal will detect a
given stimulus at a given time (Dimond and Lazarus 1974).
Another antipredator behavior is the mode of locomotion
employed by rodents, which plays a vital role in determining their ability to elude predators (Thompson 1985;
Djawdan and Garland 1988; Taraborelli et al. 2003a). The
structural complexity of the habitat may affect movement
behavior by: (1) physically impeding locomotion (Schooley
et al. 1996), (2) making movement more conspicuous and
thus riskier (Brillhart and Kaufman 1991; Borruel et al.
unpublished data), (3) providing a higher density of
resources, hence favoring lower speeds so that resource
opportunities are not missed (Brownsmith 1977), (4)
increasing protection against predators through hiding
cover (Thompson 1982; Taraborelli et al. 2003b), (5)
increasing visual obstruction, thus reducing the ability to
detect predators (Schooley et al. 1996; Ebensperger and
Hurtado 2005).
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Many animals do not continuously move through their
habitat, but show an overall pattern of intermittent
locomotion (Pennisi 2000; Vásquez et al. 2002). Intermittent locomotion, as is called by MacAdam and Kramer
(1998), Pennisi (2000), Kramer and McLaughlin (2001),
Vásquez et al. (2002) and Trouilloud et al. (2004), consists
of pauses, lasting from milliseconds to minutes, that break
up movement bursts and enable animals to scan the
surroundings (e.g., Sciurus carolinensis, Tamias striatus,
and Octodon degus). Thus, pauses, along with changes in
the duration and speed of moves, form part of a dynamic
system of intermittent locomotion whereby animals adjust
their locomotor behavior to changing circumstances
(Kramer and McLaughlin 2001).
The use of pauses may enable animals to increase
predator detection (MacAdam and Kramer 1998; Kramer
and McLaughlin 2001; Trouilloud et al. 2004). Pauses
would last a longer time in open habitats, high-risk areas,
and would play an antipredator role because they would
enhance efficiency in detecting predators and in the ability
to escape (Vásquez et al. 2002). Pauses may also help prey
become more cryptic and reduce the capture ability of
predators when they are more likely to perceive and/or
attack moving prey (Curio 1976) and may provide cavies
with chances to acquire orientation cues for moving across
the habitat (Dyer 1998). From a physiological viewpoint,
pausing may serve as a resting stage (Weinstein and Full
1992). Pauses, aside from providing direction-finding cues
or physiological recovery, may also contribute to information processing and enhanced predator detection (Dukas
1998).
The purpose of this study was to assess the influence of
predator abundance and plant structure on vigilance and
intermittent locomotion in the rodent Microcavia australis
(Rodentia, Hystricognate, Caviidae, common name: lesser
cavy). M. australis is a semi-fossorial herbivore native to
South America, with diurnal habits, a burrowing rodent
exhibiting a group social structure with low levels of
aggressiveness (Rood 1967). It dwells specifically in arid
shrub areas and sandy scrublands (Olrog and Lucero 1986;
Canevari and Fernández Balboa 2003). Groups are composed of several females, one or few males, plus the young
and juveniles (Rood 1967 and 1972). In the Central Monte,
the social groups were formed by three to six cavies
(Taraborelli and Moreno 2009). Rood (1972) and Taraborelli
and Moreno (2009) assert that the mating system in this
species is promiscuous, that females mate indiscriminately
with any male, and cavies show absence of sexual
dimorphism. This cavy displays its behavioral patterns in
the burrow area, under the cover provided by trees and/or
shrubs where predation risks are lower (Rood 1967; Tognelli
et al. 1995). Each group is associated with a burrow and the
groups are permanent, not transitory (Taraborelli 2006). The
acta ethol (2011) 14:27–33
fact that cavies congregate underground during the night and
maintain stable associations confirms that this species nests
communally and suggests that nesting associations represent
distinct social units (Ebensperger et al. 2006). Groups of M.
australis are not organized according to hierarchies (pers.
obs.). When confronted with predators, the cavies react with
a higher frequency of vigilance behavior and by fleeing
towards the burrow and/or by hiding in galleries, but not by
repelling the predators (Taraborelli et al. 2008). The cavies
never emit alarm calls in response to the presence of a
predator but simply respond with an alert posture (Taraborelli
2006, 2008). Therefore, the objective is to analyze and
compare vigilance behavior and intermittent locomotion of
M. australis in two populations located on two sites (El
Leoncito and Ñacuñán, Argentina) differing in predation
risk, plant structure, and plant availability. A specific
objective is to record predators on both sites. One proposed
prediction is that on sites with wide open areas (El Leoncito)
the number of records of intermittent locomotion and
pausing events will be higher. The other prediction is that
vigilance will be used in response to predation risk and
therefore, on both sites, vigilance time will increase with
higher predation risk.
Materials and methods
Study sites
The study was conducted in a population of M. australis in
the Monte semiarid desert, in the Man and Biosphere
Reserve of Ñacuñán (34° 2’ S, 67° 58’ W, 12,300 ha,
540 m asl) in the central-west of Mendoza (Argentina,
Ojeda et al. 1998). The climate is warm–dry semiarid; mean
annual precipitation is 329.4 mm, with 50% occurring in
the summer months (Cabrera 1976; Estrella et al. 2001).
The mesquite plant community is the most extensive and
complex, composed of three plant layers, the tree layer, the
shrub layer, and the very species-rich herb layer (Roig
1971). Total plant cover is 54.3% (Taraborelli 2006).
Potential predators are diurnal and nocturnal raptors,
carnivores, and reptiles (Contreras and Roig 1979; Ojeda
et al. 1998).
The second population dwells in the arid Monte of El
Leoncito National Park (31º 47´ S, 69º 17´ W; 76,000 ha,
2484 m asl), in the southeast of San Juan province (Argentina,
Márquez 1999). The climate is cold dry arid, with strong
diurnal, nocturnal, and seasonal temperature ranges (Bracco
and Contreras 2000; Márquez and Dalmasso 2003). Mean
annual precipitations do not exceed 100 mm, in the form of
snow and hail in winter, reaching 75 mm, and in the form of
rain and lower than 10 mm in summer (Le Houérou 1999).
In the Monte of El Leoncito, there occurs a shrubland of
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acta ethol (2011) 14:27–33
Larrea nitida with low cover (10%); the herb layer is lower
than 10 cm in height (Márquez et al. 2000; Márquez and
Dalmasso 2003). Total plant cover is 21.9% and most of the
land is barren (Taraborelli 2006). Similar to the first site,
potential predators include carnivores, diurnal, and nocturnal
raptors, as well as reptiles (Márquez 1999).
Records of predators
Records of predators were searched and taken from footprints, feces, and raptor castings in the study areas. Also,
the records were from direct observations during the
morning: 8:00–1:00 h, midday, 11:00–14:00 h, afternoon
14:00–17:00 h, evening: 17:00-20:00 h. Direct observations
were carried out during 7–11 days at three times of the year
(time of food abundance: November–February, food shortage:
April–August, and reproduction: September–March) for each
study site from 2003 through 2005. And the number of cavies
was gotten from capture, tagging, and recapture, setting
Havahart traps (25×30×91 and 18×18×76 cm; Havahart,
Lititz, Pennsylvania) and Tomahawk traps (15×15×60 cm;
Tomahawk live trap Nº 202/203, Tomahawk, USA). The traps
were set up on activity paths and around burrows (Rood 1972;
Hoogland 1995). Subjects were individualized by numbered
metal ear tags (0.6×0.2×0.05 cm; National Bandand Tag Co.
Newport, USA), by painting part of the body with innocuous
paint, depending on sex, and by making diverse drawings on
them, for example, circles, squares, vertical or horizontal
lines, letters, etc. (35 adults at El Leoncito and 11 adults at
Ñacuñán). Gentian violet was used to paint the cavies; this
substance is not toxic and is used to cure fungi. Neither
tagging nor painting has a negative effect for animal welfare,
as corroborated by Hoogland (1981), Cassini (1989), Branch
(1993), Meserve et al. (1993), Hoogland (1995), Ebensperger
and Hurtado (2005), and Ebensperger et al. (2006).
The contents of collected feces and raptor castings were
analyzed in the laboratory under magnifying glass; species
were identified by their molar teeth using keys for
identifying small mammals, guidebooks, skulls in the
IADIZA-CRICYT Collection and photographs (Olrog and
Lucero 1986; Pearson 1995). The collected feces of
predators and raptor castings with cavies' bones and hairs
were taken as a record of predation. Then, all predation
records from direct observations, footprints, feces, and
raptor castings were associated with time of the day and
season of the year. Predation rates on cavies were calculated
for each time of the year, and then, we estimated the mean
and standard error for all data.
Behavior samplings
Quantification of vigilance behavior and intermittent
locomotion was achieved through focal samplings (focal-
29
continuous, Altmann 1974; Martin and Bateson 1993;
Lehner 1996). Observations were made with binoculars
(8×40, Hoken, Wald S.A., China), tape-recorded (using
voice), and video-taped (Canon ZR-80) from an observation tower 2 m high and 30–50 m away from the burrows.
They were taken as of 8:00–13:30 till 14:30–20:30 h
(morning, midday, afternoon, evening) over 3–4 days at
three times of the year for each study site from 2003
through 2005.
These behaviors were defined as: Vigilance: alert posture
that involves a quadrupedal posture, typically the animal
“freezes” with its front legs extended and turns toward the
stimulus (Rood 1972; Taraborelli 2006). Intermittent
locomotion: slow or fast moves with the body and head
close to the ground, interrupted every two or three steps by
short pauses where the head adopts an erect position in an
attitude of vigilance, and so on (MacAdam and Kramer
1998; Pennisi 2000; Kramer and McLaughlin 2001;
Vásquez et al. 2002; Taraborelli 2006).
The duration and frequency of vigilance behavior and
intermittent locomotion (moves and pauses) were recorded
for each animal on each sampling date. Number and
duration of stops or pauses in intermittent locomotion were
recorded as well. Frequency is the total number of
occurrences of a behavior (Martin and Bateson 1993). For
comparing behaviors between sites, rates (frequency of
behavior/observation period in minutes), and proportions
(duration of behavior in minutes/observation period in
minutes) were obtained for each site (Martin and Bateson
1993). Observations were changed among adult cavies that
were alone or accompanied by more individuals of the
group and not repeated for a same individual or group of
cavies. We used only the first observation of each
individual.
Statistical analysis
The χ2 test was applied to compare the records of
predators throughout the day at both sites, and Pearson
residuals (r = f observed – f expected/√f expected) were
used to find differences between said records. The
Kruskal–Wallis test was employed to search for differences in predation rates on cavies among the periods of
the year at both study sites. ANCOVA was used to
compare the mean rates and proportions of behaviors
(vigilance, intermittent locomotion, and pauses made per
intermittent locomotion event), between sites, times of the
year, and times of the day. ANCOVA was applied to check
for differences between sites in the rate of stops per
intermittent locomotion. Group size was the covariance.
Post hoc tests (Tukey test, p<0.05) were performed among
the variables considered. Results are expressed as sampling mean ± standard error.
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Results
Record of predators
The density of cavies was 7.22±0.5 adults/ha at El Leoncito
and 1.91±0.22 adults/ha at Ñacuñán. There were no differences in the predation rate on cavies among the periods of the
year for each site (Ñacuñán: Kruskal–Wallis test, H=1.88,
df=2, p=0.501; El Leoncito, Kruskal–Wallis test, H=1.22,
df=2, p=0.332). A total of nine groups were defined at
Nácuñán and 13 at El Leoncito. Social groups were formed
by 5–6 individuals at El Leoncito and 3–4 at Ñacuñán.
Predators at Ñacuñán are diurnal raptors all throughout
the year (Buteo polyosoma, Milvago chimango, 23 total
records) with a peak of records at midday, 1.1±0.15
raptors/cavy (mean ± standard error), followed by the
morning and the afternoon, 0.5±0.1 raptors/cavy, and lower
records in the evening 0.3±0 raptors/cavy. And mammalian
carnivores (Lycalopex gymnocercus, Galictis cuja, Conepatus chinga, Felis catus, seven total records) are the other
predators, with 0.09±0.05 carnivores/cavy.
Predation risk at El Leoncito is constant throughout the
day (χ2 =28.27, df=3, p=0.00003). Predators recorded
across the year at El Leoncito are crepuscular and nocturnal
mammalian carnivores (25 total records) with 0.21±0.05
carnivores/cavy, such as Lycalopex sp. (records of Lycalopex culpaeus are the highest) and P. concolor. Diurnal
raptors (Athene cunicularia, Geranoaetus melanoleucus,
Buteo polysoma, Falco femoralis, Falco sparverius, Circus
cinereus, 24 total records) were recorded from the morning
to the afternoon, with 0.20±0.09 raptors/cavy.
Small cavies compose about 44% of the diet of
Lycalopex sp. and 45% of the diet of P. concolor at El
Leoncito. At Ñacuñán, the cavy was not observed to be
included in the diet of A. cunicularia or in the diet of
Lycalopex sp.
Behavior samplings
The vigilance behavior was observed in cavies located on the
edge of the vegetation, under shrubs, and/or trees or in open
spaces (Ñacuñán, 11 adults and five pair of individuals
observed, El Leoncito, 28 adults and 23 pairs of individuals
observed). Concerning vigilance proportion between sites,
proportion (duration) was significantly higher at Ñacuñán
(Ñacuñán 0.19±0.02 min/min, El Leoncito 0.12±0.01 min/
min; F1 =8.6, p=0.0036, df=1, N=67). A difference in
vigilance proportion along the day is observed only at
Ñacuñán, where the peak of vigilance is at midday, followed
by the morning and afternoon, and vigilance behavior is low
in the evening; at El Leoncito, vigilance is constant
throughout the day (F3 =1.07, p=0.021, df=3, N=67;
Fig. 1). Vigilance showed no differences among times of
acta ethol (2011) 14:27–33
Proportion of vigilance (min/min)
30
0.4
c
0.3
0.2
0.1
b
b
a
ab
a
a
a
0
morning midday afternoon evening
Period of day
El Leoncito
Ñacuñán
Fig. 1 Vigilance proportion (vigilance duration in minutes/minutes of
observation) along the day at El Leoncito and Ñacuñán. a, b, c
indicate significant differences (Tukey test p<0.05)
the year (rate. F2 =0.18, p=0.833, df=2; N=67; proportion,
F2 =0.99, p=0.373, df=2, N=67).
On both sites, intermittent locomotion was observed in
individuals solely when going across open areas and when the
cavy was alone or with only one more individual of the group.
The intermittent locomotion was recorded in seven adults and
five pairs of cavies at Ñacuñán and 23 adults and 11 pairs of
individuals at El Leoncito. Records (moves and pauses) were
significantly higher at El Leoncito (34 and Ñacuñán 12). Only
at Ñacuñán did the rate of intermittent locomotion vary along
the day, where the peak of frequency of intermittent locomotion
per minute occurred at midday, instead of in the morning and
afternoon; on the other hand, at El Leoncito, this rate was
constant throughout the day (F3 =3.4, p=0.0219, df=3, N=46;
Fig. 2). But, the proportion of this behavior did not change
between periods of the day (F3 =8.22, p=0.397, df=3, N=46).
Moreover, there were no differences in intermittent locomotion between times of the year (rate F2 =0.44, p=0.644, df=2,
N=46; proportion F1 =1.03, p=0.362, df=2, N=46).
With respect to the number of pauses per intermittent
locomotion event, the rate was found to be significantly
higher at El Leoncito (19±1 pauses min−1, Ñacuñán 11±2
pauses min−1; F1 = 1.12, p = 0.03, df = 1, N = 46). And
proportion (duration) of pauses per intermittent locomotion
was also significantly higher at El Leoncito (0.17±0.01
minutes/minutes, Ñacuñán 0.13±0.02 minutes/minutes; F1 =
4.02, p=0.034, df=1, N=46). Then, cavies spent approximately 17% of their time making pauses at El Leoncito and
13% of it at Ñacuñán.
Discussion
Antipredator responses in M. australis could be directly
related to the risk of predation on each site, as the duration
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Rate of intermittent locomotion (Freq/min)
acta ethol (2011) 14:27–33
31
1
0.8
b
0.6
0.4
a
0.2
a
a
ab
a
a
a
0
morning midday afternoon evening
Period of day
El Leoncito
Ñacuñán
Fig. 2 Rate of intermittent locomotion (frequency of intermittent
locomotion/minutes of observation) along the day at El Leoncito and
Ñacuñán. a, b indicate significant differences (Tukey test p<0.05)
of the vigilance behavior is significantly higher at Ñacuñán,
where the vigilance peak is at midday, followed by the
morning and the afternoon, and where vigilance is low in
the evening. At Ñacuñán, the major risk of predation is
from raptors, predators that overlap with the period of
activity of cavies, with a peak of records at midday
followed by the morning and the afternoon, and lower
records in the evening. And records of mammalian
carnivores are constant throughout the day (Taraborelli
2006). At El Leoncito, both vigilance predation risk are
constant throughout the day. Raptors have been recorded
from morning to afternoon and mammalian carnivores
would be overlapping in the early morning and in the
evening (Taraborelli 2006). Other studies and a standard
model of optimal vigilance behavior have found that an
increase in the rate of predator attacks leads to an increase
in vigilance (Lima 1987; Sundell and Ylönen 2004).
Therefore, vigilance would respond to predation risk
because vigilance time increases when the number of
predator records is higher. Then, vigilance proportion could
be an indicator of predation risk.
Cavies adjusted their locomotion behavior according to
the type of habitat used. Intermittent locomotion was
observed for adults and juveniles on both sites, when the
individual was alone or with only one more individuals of
the group and when going across open areas. Lima (1987)
described that when distance to the plant cover increases,
the likelihood of escaping decreases, since predators prefer
to attack in open areas. Therefore, the area of danger
increases with distance from a refuge (Taylor 1998) because
predation risk per time unit is higher in open places than
near or under shrubs (Djawdan and Garland 1988; Hughes
and Ward 1993). At El Leoncito, records of intermittent
locomotion were higher than at Ñacuñán. This could be due
to the fact that open areas at El Leoncito are wider (80%
approximately), and to the cavies moving from one burrow
to another and in search for food among three to four
patches of Larrea nitida, whereas cavies at Ñacuñán
restricted their activity to only one burrow under a complex
plant structure (tree, shrub, and herb layers; Ebensperger et
al. 2006; Taraborelli 2006). At El Leoncito, cavies travel
longer distances than they do at Ñacuñán; for example, at
El Leoncito, distances traveled are 10–100 m, whereas at
Ñacuñán they are 6–17 m (Taraborelli 2006).
At El Leoncito, the number and duration of pauses per
intermittent locomotion event was significantly higher than
at Ñacuñán. Cavies made 19±1 pauses min−1 and spent
17% of their time in this stance at El Leoncito. At Ñacuñán,
they made 11±2 pauses min−1, with pauses taking 13% of
their time. For example, gray squirrels approaching a food
source away from forest cover made 22 pauses min−1 and
spent 35% of their time pausing, whereas those carrying a
nut to a site for hoarding under forest cover made 10 pauses
min−1, which took them 14% of their time. Pausing
increases with early detection of predators (MacAdam and
Kramer 1998). Longer pausing may increase the efficacy of
antipredator vigilance because it enhances predator detection.
During pauses, cavies often adopted a crouching posture
with the head raised in an alert stance. This position may
allow M. australis to visually scan the surroundings,
increasing their visual detection of dangerous events, and
hence decreasing their reaction time to flee from potential
predators, as it occurs in other social rodents (Blumstein
1998; MacAdam and Kramer 1998; Kramer and McLaughlin
2001; Trouilloud et al. 2004). Intermittent locomotion may
be advantageous, therefore, in providing brief periods of
visual field stability (Kramer and McLaughlin 2001). The
static position adopted during pauses may also improve
hearing performance in comparison to running behavior
when audition may be interfered by the noise generated by
the very movement of the animal (Kramer and McLaughlin
2001; Vásquez et al. 2002). MacAdam and Kramer (1998)
and Trouilloud et al. (2004) found that S. carolinensis and T.
striatus increase their pauses with the head raised when
approaching situations of higher risk, for instance when
foraging farther from their burrows. Vásquez et al. (2002)
reported that the pauses in O. degus lasted longer in open
habitats and high-risk areas. And these interruptions would
play an antipredator role since they would improve antipredator vigilance (Trouilloud et al. 2004).
Pauses might also make prey more cryptic and reduce
capture ability if predators are more likely to detect and/or
attack moving prey because such motionless periods may
also reduce the probability that visually or auditory
sensitive predators will detect the prey (Curio 1976; Kramer
and McLaughlin 2001). Also, Vásquez et al. (2002) noted
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32
that it was far more difficult for the predator to detect a
motionless degu than a moving one. Therefore, when alone
or with only one more individual of the group, M. australis
would adjust its antipredator behavior (e.g., intermittent
locomotion) according to the type of habitat used, particularly when going across open areas where there are
situations of higher risk.
On the other hand, differences found between populations might have an evolutionary explanation. Sassi
(unpublished data) found that analyses of genetic differentiation (ISSR markers) for M. australis revealed that the
population at Ñacuñán constitutes a group and that
populations at El Leoncito compose a different group, so
there could be two separate gene pools, one at Ñacuñán and
the other one at El Leoncito. However, the levels of genetic
variability show that each population would maintain a
large effective size and a high level of intra- and interpopulation polymorphism. From the genetic viewpoint,
plasticity of this species would depend on the heterogeneity
of the environment it has to cope with. In this respect,
phenotypic plasticity plays a key role in the ecological
success of organisms and in the local adaptation of the
species.
Acknowledgments This study was partially financed by CONICET,
PICT Nº 03281, and PIP 02884. The authors wish to express their
thanks to M. C. González, N. Borruel, A.J. Sandobal, M. Martínez,
and V. Bauni for their cooperation in the field. Thanks also to N.
Horak for the English version of the manuscript and to Dr. R. Ojeda
for his contributions in reviewing the manuscript and for the literature
provided.
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