DOI: 10.5061/dryad.qnk98sfdx
title: Alternative responses by two species of jumping spiders to unpalatability and toxicity in prey

description: A key challenge for generalist predators is avoiding toxins in prey.
 Species-specific strategies range from total avoidance of distasteful (and
 potentially toxic) prey to the use of physiological mechanisms to
 metabolize toxins after consumption. We compare two species of jumping
 spiders, Habronattus trimaculatus and Phidippus regius. Based on several
 anecdotal observations and other aspects of their biology, we hypothesized
 a priori that H. trimaculatus would be (1) less willing to feed on
 unpalatable prey and (2) more susceptible to toxins that are consumed
 compared with P. regius. In Experiment 1, we presented spiders of both
 species with size-matched quinine-dipped crickets. Consistent
 with our hypothesis, all H. trimaculatus attacked and rejected them while
 all P. regius attacked and consumed them. In Experiments 2 and 3 we
 assigned spiders of both species to experimental feeding treatments with
 varying levels of toxicity (using toxic springtails, Folsomia candida) and
 assessed effects on their growth. Spiders of both species readily fed on
 the springtails. Collectively, results from these two experiments suggest
 that springtails have negative effects on both species, but that these
 effects are stronger in H. trimaculatus. Habronattus has a unique red
 retinal filter pigment (not found in Phidippus) that likely improves their
 ability to discriminate reds and oranges. The evolution of this unique
 visual system may have been driven by their heightened susceptibility to
 prey toxins, and thus the benefits of avoiding prey that advertise toxins
 with long-wavelength colors.  
description: The attached data excel file is arranged into three experiments
 which are found on different labeled excel worksheets. For each experiment
 the data are as follows: <strong>Experiment
 1:</strong> <b>Determining the willingness of spiders to
 consume distasteful prey.</b> In order to
 determine if the two species of spiders differed in their willingness to
 consume distasteful prey we collected the following data: stage (adult or
 immature), sex (male or female), and whether spiders attacked-and-consumed
 (yes or no) or attacked-and-rejected (yes or no) quinine dipped
 crickets. <b>Experiment 2: Determining the
 effects of toxins on spiders once toxic prey have been
 consumed.</b> To determine whether the two spider
 species were affected by the consumption of toxic prey we collected the
 following data metrics from three feeding treatments (control = no
 prey; crickets-only; springtails-only): spider ID, stage (adult or
 immature), sex (male or female), carapace width (mm), pre-trial weight
 (g), 4-week weight (g), mass change (the difference between 4-week and
 pre-trial in grams).  <b>Experiment 3:
 Determining the extent to which spiders were feeding on toxic prey and
 re-examining the effects of toxic prey once consumed.</b>
 First, to assess whether spiders were feeding on springtails we
 conducted 15-minute visual observations and recorded whether or not (yes
 or no) spiders were feeding on a springtail. Second, to re-examine the
 effects of toxic prey once consumed by the two species we collected the
 following data metrics from two feeding treatments (cricket only = 1/4  of
 the spider's body size; cricket + springtail = one pinhead cricket,
 1/4 of the spider's body size, plus 3-4 springtails): spider ID,
 stage (all spiders were immature), initial collection size (body length
 estimate, mm), carapace widths (mm), pre-trial weight (g), 4-week weight
 (g), mass change (the difference between 4-week and pretrial weights in
 grams). Finally, to examine mortality we recorded whether spiders died
 (yes or no), day of death, and time to death (the number of days between
 the start of feeding treatments and day of death).