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\begin{document}

\title{Fake news? The impact of information mismatch in mating behaviour}



\author[1]{Leonor Rodrigues}%
\author[2]{Sara Magalhaes}%
\affil[1]{Centre for Ecology Evolution and Environmental Changes}%
\affil[2]{Faculdade de Ciências, Universidade de Lisboa}%


\vspace{-1em}



  
  \date{May 27, 2024}


\begingroup
\let\center\flushleft
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\selectlanguage{english}
\begin{abstract}
Multiple cues are often used for mate choice in complex environments,
potentially entailing mismatches between different sources of
information. We address the consequences thereof for receivers using the
spider mite Tetranychus urticae, in which virgin females are highly
valuable mates compared to mated females, given first male sperm
precedence. Accordingly, males prefer virgins and distinguish them using
cues from the females and/or that are present on the substrate. Whereas
the former are more reliable, the latter may allow for a faster or more
long-distance response. However, there can be mismatched information
between cues as females move and/or mate. Here, we tested the
consequences thereof by exposing males to mated or virgin females on
patches previously impregnated with cues deposited by females of either
mating status. Male mating attempts were solely affected by substrate
cues while female acceptance and the number of mating events were
independently affected by both cues. Copulation duration, in contrast,
depended mainly on the mating status of the female, with the number of
copulations and the total time spent mating being intermediate in
environments with mismatched information. Ultimately, male survival
costs mirrored male investment in mating. These results suggest that, in
environments with mismatched information, the substrate cues left by
females are instrumental for males to find their mates, but they can
also lead to males paying survival costs without the associated benefit
of mating effectively, or suffering reduced costs at the expense of
losing effective mating opportunities. The benefit of using multiple
cues will then hinge upon the frequency of information mismatch, which
itself should vary with the dynamics of populations.%
\end{abstract}%



\sloppy


\textbf{Fake news? The impact of information mismatch in
mating~behaviour}

Leonor R. Rodrigues and Sara Magalh\selectlanguage{ngerman}ães

cE3c: Centre for Ecology, Evolution, and Environmental Changes, Faculty
of Sciences, University of Lisbon, Edifício C2,3º piso, 1749-016 Lisboa,
Portugal

\emph{Corresponding author} : Leonor Rodrigues,

\emph{alrodrigues@fc.ul.pt}

\textbf{Funding}

This work was supported by the European Research Council (grant
number~COMPCON, GA725419) to SM and the Fundação para a Ciência e a
Tecnologia (grant number EXPL/BIA-EVL/0131/2021) to LRR.

\textbf{Acknowledgements}

The authors wish to thank Matheus Rocha for having performed the
experiments, Flore Zélé for creating the spider mite populations used in
this experiment and Inês Santos and Cátia Eira for maintaining them. The
authors have no conflict of interest to declare.

\textbf{Data Availability Statement}

Analyses reported in this article can be reproduced using the data and
code that will be publicly available in Dryad upon acceptance. For
reviewing purposes, we provide the corresponding private link:
https://datadryad.org/stash/share/OCdqzNAQDww5T9e8jtUIUiWmTyptqxkcOAf6nQtc8UY

\textbf{Abstract}

Multiple cues are often used for mate choice in complex environments,
potentially entailing mismatches between different sources of
information. We address the consequences thereof for receivers using the
spider mite \emph{Tetranychus urticae} , in which virgin females are
highly valuable mates compared to mated females, given first male sperm
precedence. Accordingly, males prefer virgins and distinguish them using
cues from the females and/or that are present on the substrate. Whereas
the former are more reliable, the latter may allow for a faster or more
long-distance response. However, there can be mismatched information
between cues as females move and/or mate. Here, we tested the
consequences thereof by exposing males to mated or virgin females on
patches previously impregnated with cues deposited by females of either
mating status. Male mating attempts were solely affected by substrate
cues while female acceptance and the number of mating events were
independently affected by both cues. Copulation duration, in contrast,
depended mainly on the mating status of the female, with the number of
copulations and the total time spent mating being intermediate in
environments with mismatched information. Ultimately, male survival
costs mirrored male investment in mating. These results suggest that, in
environments with mismatched information, the substrate cues left by
females are instrumental for males to find their mates, but they can
also lead to males paying survival costs without the associated benefit
of mating effectively, or suffering reduced costs at the expense of
losing effective mating opportunities. The benefit of using multiple
cues will then hinge upon the frequency of information mismatch, which
itself should vary with the dynamics of populations.

\textbf{Keywords:} mate choice; mating costs; reproductive behaviour;
spider mites; first male sperm precedence



\textbf{Introduction}

In many taxa, individuals use multiple sources of information to search
for mates and engage in copulations . Along the years, several
hypotheses have been put forward to explain the role of different cues
in mate decision (see detailed classifications in : a) each cue may
convey information about different mate qualities, the cues together
increasing the accuracy of assessment, b) cues can be redundant but
together improve discrimination, reducing errors associated to each cue,
and/or c) cues can work differently in distinct environments and/or at
dissimilar distances. The use of multiple cues is particularly useful in
varying and complex environments , as information transfer to receivers
may be disrupted in such environments due to excess noise and/or a
mismatch between cues .

Mismatches among cues can occur when cues have different
susceptibilities to changes in the environment, or when they persist for
different periods of time . For instance, during development, the
butterfly \emph{Pieris rapae} relies on both temperature and the
photoperiod to evaluate climatic conditions at adult emergence. Climate
warming promotes the mismatch between these two cues, affecting
temperature but not the photoperiod, which can result in a sub-optimal
wing melanisation phenotype upon emergence . Likewise, mate quality can
be perceived via both ephemeral cues (e.g., behavioural traits), and
more permanent cues such as morphological traits . That is the case of
the field cricket (\emph{Gryllus campestris} ) that uses both body size
and chirp rate in males as indicators of mate quality, typically giving
priority to body size, the most permanent cue . In variable
environments, however, fixed cues may become unreliable indicators of
male quality , in which case the use of ephemeral cues may be favoured.

Whereas the use of multiple cues can be beneficial in many contexts,
their use also come at some costs. First, processing information
stemming from multiple cues is expected to lead to increased energetic
and cognitive investment . Second, when there is mismatched information,
using multiple cues may lead to an inaccurate response from the
receiver. When this perception of cues concerns mate choice, costs for
receivers are likely to be associated with missing opportunities of
mating with a suitable mate or with investing in matings with unsuitable
mates . For example, in \emph{Gryllus integer} males the stimuli of
heterospecific females compromise conspecific chemical cues detection
during mating trials, leading to equal intensity of heterospecific and
conspecific courting . Therefore, the optimal use of multiple cues and
corresponding mating behaviour should depend on the balance between the
costs of acceptance and rejection errors .

The existence of cues mismatch in mate choice can be particularly
disadvantageous in species with first male sperm precedence, where
female mating status discrimination is essential for male mating
success. Indeed, under this pattern of sperm precedence, mating with
mated females provides low, if any, fertilization opportunities, whereas
mating with virgin females strongly contributes to reproductive success
. Accordingly, it has been shown that males of these species have the
ability to discriminate female mating status, preferring the virgins,
and modulate their reproductive behaviour based on the cues presented by
females . Yet, the behaviour of males when discordant information
concerning the female mating status is provided, as well as the
associated costs thereof, remain largely unknown.

To fill this gap, we observed the mating behaviour of male and female
two-spotted spider mites (\emph{Tetranychus urticae)} in environments
with information concerning the female mating status coming from two
sources, the female itself and the cues it leaves in the substrate.
Spider mites have first male sperm precedence and, accordingly, males
prefer to mate with virgins, basing their decision upon volatiles
released by females into the air and/or substrate cues remaining on the
patches . Furthermore, matings with virgin females take less time to
start, are longer, and induce more survival costs in males than matings
with mated females . All this suggests that male reproductive investment
in matings with virgins and with mated females is not the same. However,
matings involving mated females are frequently observed in laboratory
populations , despite often leading to lower fecundity . This suggests
that discrimination in this species is not perfect and may depend on the
composition of cues present in the environment. Spider mite populations
occur in variable environments, as they colonize seasonal resources such
as agricultural crops . Moreover, they disperse among patches after a
variable number of generations in the same patch, following a subdivided
haystack population structure . This results in a scenario of cyclic
waves of virgin and mated females across time within the same plant,
which fosters the conditions for a temporal mismatch between the
different cues signalling female mating status. Here, we tested the
consequences of information mismatch within this context. We predict
that, in an environment with information mismatches, the chance of
mating with less favourable females and losing valuable mating
opportunities is higher than in environments with concordant
information, which should influence the overall mating costs suffered by
males.

\textbf{Materials and Methods}

\textbf{Spider mite populations and rearing conditions}

The spider mite population used was created from an outbred population
of \emph{Tetranychus urticae} , established in 2016 at the host
laboratory, by merging six populations collected in the field around
Lisbon in 2013 . The population was reared in large numbers
(\textgreater{}200) on bean plants (\emph{Phaseolus vulgaris} ,
Fabaceae, var. Contender; Germisem Sementes Lda, Oliveira do Hospital,
Portugal), under controlled conditions (25°C, photoperiod of 16L: 8D).
All bean plants used in the experiment were grown for 14 days in an
herbivore-free climatic chamber under the same controlled conditions as
spider mites.

\textbf{Experimental Setup}

All experiments were done on bean leaves. Females and males were
isolated from the base population on detached leaves at the quiescent
stage, immediately before completing the last moult. This way, all
individuals used in the experiment shared the same age-at-maturity, and
virginity was ensured in both sexes before they were allocated to
different treatments.

Previous work shows that to choose between virgin and mated females male
spider mites use volatiles emitted by females and substrate cues left by
females on patches . Based on this information, we created with our
setup the conditions for mate discrimination to take place in an
environment in which there was matching information (e.g., virgin
females on patches previously impregnated with cues released by virgin
females) or in which there was a mismatch between the information
released by the females present on the patch and the cues that were left
on the substrate by previous females (e.g., virgin females on patches
previously impregnated with cues released by mated females). To create
these different environments for males, multiple groups of 10 virgin
females were randomly assigned to patches (leaf discs of 2.55
cm\textsuperscript{2}) with 3 virgin males. Behaviour was observed for 1
hour and, when matings occurred, females were transferred in groups of
10 to a new empty patch of the same size. Simultaneously, groups of 10
virgin females were directly transferred to similar empty patches
without ever being in contact with males. Both types of females were
left on those patches during 24h such that they could release cues that
remained on the substrate. Those females were then removed, and 5 new
females (either mated or virgin) were placed on those patches.
Subsequently, one focal male was added to all patches. Henceforth, for
simplicity, we refer to the cues left on the patch by virgins or by
mated females that were removed prior to the beginning of the mating
sessions as ``substrate cues'' and the information emitted by females
present on the patch (including their own behaviour) as ``female mating
status''. Note that, although we are aware that chemical information is
sufficient for mate choice (Rodrigues et al. 2017), it is possible that
other cues or signals (e.g., tactile, visual) are used by males as well
(Royalty et al. 1993). In any case, we assume that the information
provided by the presence of a female is composed of multiple cues that
are concordant, and thus, for simplicity, consider ``female mating
status'' a unit of information. Likewise, substrate cues include web,
faeces, eggs and any chemical information left behind by females; once
more we consider those a unit of information. We cannot rule out the
possibility that new substrate cues are being deposited by the females
present in the patch, but given the short duration of trials, these are
not expected to play a significant role in the behaviours described.

Male and female behaviour, i.e., the number of male mating attempts, the
frequency of female acceptance, the number of mating events and
copulation duration were observed for 1 hour. A mating attempt was
registered whenever a male touched the female with the two front legs
and started bending its opisthosoma . Whenever a mating attempt resulted
in the insertion of the male aedeagus into the female abdomen for more
than one minute, the observer registered it as the occurrence of a
mating event . It has been shown that females can reject male mating
attempts by moving away from them (Rodrigues et al. 2020). As such, we
also studied the frequency of female acceptance, calculated as the
number of mating events over the number of mating attempts. Copulation
duration was registered as the time in seconds a male spent with his
aedeagus inside a female. Note that females were not removed from the
patch during a mating session, so mating events could have occurred with
mated females in patches with virgin females at later stages of the
mating session.

Subsequently, males were transferred individually to a new patch (2.55
cm\textsuperscript{2}), made from uninfested bean plants, and their
survival was followed daily, to measure whether different mating
histories would translate into a longevity cost. Death was classified as
natural (i.e., the corpse was found on the patch) or censored (i.e.,
males died by drowning or by being accidentally stuck in the leaf or
squeezed).

This experiment was carried out in 21 mating sessions divided in 8 days,
and in total, 84 males and 420 females, corresponding to 21 males and
105 females per treatment (i.e., combination of type of substrate cues
and female mating status) were observed.

\textbf{Statistical analyses}

All analyses were carried out using the R statistical package (v.
3.5.2). The same model structure was followed for the analysis of all
traits: the substrate cues (i.e., cues left on the patch by virgins or
by mated females that were removed prior to the beginning of the mating
sessions) and the female mating status (i.e., virgin or mated females
present on the patch during the mating session) were fitted as fixed
explanatory variables, whereas block (the day and time of the day at
which the experiment was done) was fitted as a random explanatory
variable (see Table S1).

Copulation duration was examined as ``copulation duration of the first
mating only'' and ``copulation duration across mating events''. In the
analysis of the latter variable, the order of each copulation (i.e.,
whether it was the first, second, third mating, etc) was added as a
covariate. All possible interactions between fixed factors were
included.

The number of mating attempts and the number of mating events were
analysed using a Poisson distribution (\emph{glmer} , lme4 package; .
The frequency of female acceptance was analysed using a binomial
distribution (\emph{glmer} , lme4 package), with the formulation of the
dependent variable including the number of female rejections and
acceptances within a \emph{cbind} function. The duration of the first
mating and the copulation duration across events were tested for
normality and analysed using linear mixed-effect models (\emph{lmer} ,
lme4 package; . Male survival was analysed using a Cox proportional
hazards mixed-effect model (\emph{coxme} , coxme package; , with the
death of males being classified as natural or censored. This model
included the number of matings as a covariate.

All maximal models were simplified by sequentially eliminating
non-significant terms from the highest- to the simplest-order
interaction . The significance of the explanatory variables was
determined using Wald F tests, for continuous distributions and
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2} tests for discrete distributions .

\textbf{Results}

Results from all statistical analyses are presented in Table S2. Males
approached females more often in patches with substrate cues of virgin
females, independently of the mating status of the females present on
the patch (substrate cues x mating status:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=1.104, P=0.293; patch cues:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=54.323, P\textless{}0.01; mating
status: \selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}= 2.055, P= 0.152; Fig.
1a). Virgins accepted male mating attempts more often than mated females
and the frequency of female acceptance was higher in patches with cues
of virgin females (patch cues x mating status:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=2.625, P=0.105; patch cues:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=8.553, P\textless{}0.01; mating
status: \selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}= 64.252, P=
P\textless{}0.01; Fig. 1b). The number of mating events was also
affected by both the substrate cues and the mating status of the female
independently (patch cues x mating status:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=1.274, P=0.259; patch cues:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=35.445, P\textless{}0.001; mating
status: \selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}= 17.89, P\textless{}0.001;
Fig. 1c). Indeed, the number of mating events was lower when matings
were with mated vs virgin females and when they occurred on patches with
cues of mated vs virgin females (Fig. 1c).

The first mating of a male lasted longer when it involved virgin females
and when it occurred in patches with cues of virgins than when it
involved mated females and occurred on patches with cues from mated
females (patch cues x mating status: F\textsubscript{1,60}=0.002,
P=0.966; patch cues: F\textsubscript{1,61}=4.737, P=0.033; mating
status: F\textsubscript{1,61}=70.367, P\textless{}0.001; Fig. 2a).
Copulation duration was always significantly higher in patches with cues
of virgins than in patches with cues of mated females (patch cues:
F\textsubscript{1,72.70}=4.624, P=0.035; Fig. 2c) but it significantly
decreased across mating events and this decrease was steeper when males
were placed in patches with virgin females (copulation order x mating
status: F\textsubscript{1,364.06}=5.652, P=0.018).

Male survival on patches with cues left by virgin females and the
presence of virgin females was reduced compared to that of males on
patches with cues left by mated females or with mated females present
(patch cues x mating status:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=0.496, P=0.481; patch cues:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=4.283, P=0.038; mating status:
\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}= 8.774, P= 0.003; Fig. 3). The
number of matings did not influence male survival
(\selectlanguage{greek}χ\selectlanguage{english}\textsuperscript{2}\textsubscript{1}=0.051, P=0.821).

\textbf{Discussion}

Here we examine the impact of multiple cues and the potential resulting
information mismatch on the mating behaviour of spider mites. We found
that the number of mating attempts was only influenced by cues left on
the patch prior to the mating sessions, being higher in patches with
cues of virgins. In turn, female acceptance was affected by both
substrate cues and the mating status of the females, being the highest
in patches with virgins and with substrate cues of virgin females and
the lowest on patches with mated females and with substrate cues of
mated females. As a consequence, the number of mating events was
affected by both substrate cues and the mating status of the females,
such that the number of copulations was intermediate in environments
with mismatched information. Once copulation started, its duration
seemed to depend mainly on the mating status of the female being
fertilized, with the overall amount of time invested in mating being
higher in matings with virgins than with mated females and intermediate
in environments with mismatched information. Ultimately, male survival
mirrored the reproductive investment of males, with patches in which
there was mismatched information showing intermediate survival costs.

In species with first male sperm precedence, like spider mites and many
spiders, the sperm from the first insemination sires most of the
offspring, thus virgins are more valuable mates than mated females.
Accordingly, males exhibit a preference for virgin females, in this and
other species with the same pattern of sperm precedence . Such result is
recapitulated here in patches with concordant cues, with mating
eagerness, copulation duration and survival costs being the highest in
patches with virgins.

When exposed to discordant information males based their pre-copulatory
mating behaviour solely on the substrate cues on the patch. These cues
are obviously less reliable determinants of the status of the female on
those patches than information emanating from the female itself. Thus,
the fact that pre-copulatory mating behaviour is triggered by substrate
cues only suggests that these cues are the most far-reaching of the two,
being beneficial in mate searching. A non-exclusive alternative is that
this less accurate cue is cheaper to assess, in which case it may pay
off to consider it alone (Fawcett and Johnstone 2003). In the field
cricket (\emph{Gryllus integer} ), calling songs are used as
long-distance cues to find mates while short-range chemical cues are
employed to assess mate quality (Lenard \& Hedrick 2010). Interestingly,
being exposed to attractive long-distance cues results in a quicker
positive response to short-distance cues, which may suggest a reduced
investment in the assessment of the latter cue in this species (Lenard
\& Hedrick 2010). A similar pattern could be taking place here. The use
of more unreliable information in pre-copulatory mating behaviour might
help explain why, in spider mites and perhaps in species with a similar
pattern of sperm precedence, matings with mated females are frequently
observed, despite their weak reproductive value.

Unlike male eagerness, female acceptance depended both on the substrate
cues and on the females' own mating status, with increased acceptance in
mated females and reduced acceptance in virgins in environments with
mismatched information, compared to concordant environments. Possibly
mated females accept more matings in patches with substrate cues of
virgins because those are the patches in which the number of male mating
attempts is the highest and thus, resistance is expected to be more
costly. This strategy, called ``convenience polyandry'', should occur
under intense harassment, when by accepting more mates than their
optima, females suffer fewer costs than by resisting them . Such is the
case for instance in female water striders that modify their mating rate
based on the relative costs of mating and of resisting mating attempts .
In turn, reduced acceptance of virgin females in patches with substrate
cues of mated females could be a byproduct of male's reduced eagerness
to mate in those patches, that may result in meek, and thus easy to
reject, mating attempts. Importantly, because females' pre-copulatory
behaviour depended both on their own mating status and on the substrate
cues present but that of males only relied on substrate cues, the
response of the two sexes was not aligned, resulting in intermediate
number of mating events in environments with mismatched information.

Once copulation started, the response of males seemed to be more
affected by the mating status of the female mating than by substrate
cues present in the environment. This is probably because, once males
reach the females, they have access to the more reliable cues emanating
from the female itself, and can thus use those to accurately modulate
their post-copulatory strategies. Still, substrate cues played a, albeit
less significant, role in copulation duration. Indeed, when exposed to
virgin cues, males mated for a longer period with both virgin and mated
females than when exposed to cues of mated females. This suggests the
information obtained before mating keeps influencing mating behaviour
even when more accurate cues are available.

The response of males to multiple cues, including both pre- and
post-copulatory behaviours, must come at some costs. Previously, it was
shown that, in male spider mites, survival is affected differently
depending on the mating status of their reproductive partners : matings
with virgin females result in high offspring yield but reduced male
survival, while matings with mated females lead to no offspring but also
fewer survival costs. Again, being exposed to discordant cues influenced
this trait. First, we saw that, in patches occupied by mated females,
males had lower survival when substrate cues were from virgins than when
they were from mated females only. It seems that in these cases, the
existence of a mismatch leads to an over-investment in ineffective
matings. This behaviour could be maintained not to risk rejecting mating
opportunities with suitable females, as proposed by Reeve . In his
model, Reeve shows that males are expected to exhibit more permissive
mating acceptance thresholds as the value of the desirable female
increases and the costs of accepting a wrong female decreases, which are
the exact conditions we find in this system. Indeed, virgin females are
highly valuable compared to mated females and the costs for males of
mating with mated females is quite low . An equivalent decrease of the
acceptance threshold would be expected if assessing multiple cues was
too costly, in which case one would expect individuals to neglect the
least reliable cue , that is the cues left on the substrate by females.

Male survival in patches with mismatches between cues is higher than in
patches with cues of virgins only. In these patches, the number of
mating attempts is similar to that in patches with virgins, but the
total number of matings and the total amount of time spent copulating is
significantly lower. This suggests that the number of mating events
and/or postcopulatory events are important determinants of male mating
costs, ensuring a reduction in the costs of reproduction in mating with
less valuable females. Moreover, male survival was higher in patches
with virgin females but substrate cues of mated females, than in patches
with cues of virgins only. Therefore, it seems that in these conditions,
males invest less in effective matings, possibly via a reduction in the
number of male mating attempts and in the total amount of time spent
mating. However, we have not tested whether the observed reduction in
copulation duration is translated into reduced mating success and
previous results suggest copulation duration does not correlate
positively with offspring production .

We did not measure the chemical composition of the different sources of
information that males were exposed to, nor do we know exactly which
cues are used by males to choose between virgin and mated females.
Indeed, we know that substrate cues and volatiles emitted by females are
sufficient for male choice (Rodrigues et al. 2017) but other cues, such
as visual and tactile cues, not being necessary, may play a role
(Royalty et al. 1993). In addition, substrate cues themselves,
considered here as a unit of information, include web, faeces, eggs and
any chemical compounds deposited by females in the patches. Web is used,
among other functions, in mate searching behaviour (Penman and Cone
1972, 1974) but the role of other substances is unknown. Still, we can
make a few inferences from the patterns observed in male behaviour upon
exposure. For example, we do not know whether the chemicals used by
males to assess females themselves are the same present on the
substrate. This is however not very likely, as different components of
male mating behaviour react differently to the different combinations of
cues from virgins and/or mated females. Another possibility is that only
virgin females produce cues. Our results are compatible with this
possibility. Regardless, this would still mean that males are exposed to
situations in which the information stemming from the females themselves
and the substrate they occupy are either concordant or discordant.

The optimal use of information and corresponding behaviour should depend
on the balance between the costs of acceptance and rejection errors and
this, in turn, should vary with the dynamics of the social and
ecological environment, which set the stage for different selection
pressures to operate upon mating cues and their perception (Alpedrinha
et al. 2019). In spider mite populations, individuals disperse among
patches after a variable number of generations in the same patch,
following a subdivided haystack population structure . Such cycles of
colonization-expansion foster the conditions for information mismatches
within a patch. Indeed, while the information emitted by females will
change simultaneously with the shift in mating status, the cues left on
the patch should remain unaltered for some time after this shift. While
these cues seem to be less reliable than the information provided by
females themselves, they are probably accessible at a larger scale,
allowing males to move in the direction of areas with suitable mates
(i.e., virgins) before their competitors. This should be highly
advantageous in species with first male sperm precedence. These findings
could thus have important implications for mating system evolution,
potentially helping to explain why female multiple mating is maintained
in species with first male sperm precedence. Still, the benefit of using
multiple, sometimes discordant, cues will hinge upon the frequency of
discordance among them, which itself should vary with the dynamics of
populations.

\textbf{References}

\textbf{Figure 1. Male and female pre-copulatory mating behaviour and
the corresponding number of mating events in response to substrate cues
and female mating status.} a) Number of male mating attempts, b)
proportion of mating attempts accepted by females and c) number of
mating events. Males were exposed for 1 hour to 5 virgin or mated
females in patches impregnated with cues of virgin or mated females.
Circles represent individual replicates. Black circles --patches with
mated females; grey circles -- patches with virgin females; open circles
-- patches with cues of virgin females; full circles -- patches with
cues of mated females.\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image1/image1}

\end{center}
\end{figure}

\textbf{Figure 2. Duration in seconds of a) first matings and b) across
mating events, in response to patch cues and female mating status.}Males
were exposed for 1 hour to 5 virgin or mated females in patches
impregnated with cues of virgin or mated females. Circles represent
individual replicates. Black circles --patches with mated females; grey
circles -- patches with virgin females; dashed lines and open circles --
patches with cues of virgin females; continuous lines and full circles
-- patches with cues of mated females.\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image2/image2}

\end{center}
\end{figure}

\textbf{Figure 3. Male survival curves in response to patch cues and
female mating status.} Male survival was followed daily after males
being exposed for 1 hour to 5 virgin or mated females in patches
impregnated with cues of virgin or mated females. Circles represent mean
values per day per treatment. Black circles --patches with mated
females; grey circles -- patches with virgin females; dashed lines and
open circles -- patches with cues of virgin females; continuous lines
and full circles -- patches with cues of mated females. Vertical bars
correspond to standard errors of the mean.\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image3/image3}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

