20th International Congress of Arachnology

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of coercive mating tactics, and female sexual cannibal-
ism. We used topical application (via dimethyl sulfoxide)
to manipulate OA and 5-HT levels at different concentra-
tions (2mg/uL and 10mg/uL). In general, males provided
with OA had significantly reduced levels of courtship in
comparison to control groups in response to isolated
female chemical cues. In live mating trials, males and/or
females were each give 10mg/uL of OA or 5-HT in a 2x2
design in order to determine whether the male or female
amine levels best predicted mating success. These live
mating trials demonstrated that female biogenic amine
levels are more likely to affect mating outcomes, likely
due to increased aggression when given OA and reduced
aggression when given 5-HT. Our findings demonstrate the
importance of OA and 5-HT in the regulation of mating
behaviors of a well-studied wolf spider, but might also lead
to further evolutionary insight into the roles of OA and
5-HT in other arachnids and arthropods.
Keywords: male courtship, female mate choice, mating
behaviors, neuromodulation, Lycosidae, Schizocosa
Poster presentation
The effects of dopamine on mating behav-
iors of a wolf spider
Brent Stoffer, Breanna Bohan, George W. Uetz
University of Cincinnati, Department of Biological
Sciences, P.O. Box 210006 Cincinnati, OH 45221, USA
An array of animal behaviors is modulated by biogenic
amines (e.g., histamine, serotonin, octopamine, norepi-
nephrine, and dopamine) that act as neurotransmitters,
neuromodulators, or neurohormones. However, the role
of these amines in the regulation of pre-copulatory and
post-copulatory mating behaviors in arthropods, and espe-
cially arachnids, is poorly understood. Dopamine (DA), in
particular, has been associated with motivation and reward
across different contexts, and is increased during copula-
tion in some vertebrates. In this study, we experimentally
elevated DA levels in male and female brushed-legged wolf
spiders, Schizocosa ocreata. Dopamine was given topically
on the cephalothorax using dimethyl sulfoxide (DMSO) as
a carrier solvent. Either the male, the female, or both sexes
was given DA and paired (1 male, 1 female) in live mating
trials. Additional control groups were included to ensure
that carbon dioxide or DMSO treatments did not affect
mating behaviors. We found that DA did not have a signifi-
cant effect on mating success or male courtship. However,
dopamine shortened the copulation duration when the
female was given dopamine. We speculate that dopamine
stimulated the reward center, giving spiders no further
motivation to mate and reducing the copulation duration.
Keywords: mating behaviors, copulation, neuromodula-
tion, biogenic amines, Lycosidae, Schizocosa
Oral presentation
Vision and visually guided behavior in the
hunting spider Cupiennius salei (Araneae:
Ctenidae)
Martin Streinzer, Axel Schmid
Department of Neurobiology, University of Vienna,
Althanstraße 14, 1090 Vienna, Austria
Cupiennius salei, a nocturnal Central American hunting
spider, serves as important model in neurobiology, neuro-
physiology and neuroethology. Aside from its remarkable
mechanosensory organs, it is equipped with eight well
developed eyes. Behavioral observations confirm that
vision is used by the spider in the context of orientation
and hunting. This presentation aims to give an overview
about experiments on visually guided behaviors in
Cupiennius. These show that C. salei is capable of visual
object detection and discrimination and likely also visual
memory. Cupiennius is further likely to use vision for
depth perception. Behavioral experiments suggest that
the main depth cue is motion induced parallax, gener-
ated during their zigzag like approaches towards target
objects. To overcome limitations of the previously used
real-world arena setup, we recently started to use Virtual
Reality (VR). Our setup consists of a large, actively driven
sphere that compensates for the spiders’ movement, and
a circum surrounding seamless projection. The projection
is updated in real time based on the spider’s own move-
ment, to create a closed-loop virtual reality environment
in which the spider can move freely. The Spider VR allows
186 DENVER MUSEUM OF NATURE & SCIENCE REPORTS | No. 3, July 2, 2016
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