In many prey taxa with aposematic coloration, prey defenses also involve signals in other modalities (odors, sounds, etc.), yet the selective forces that have driven multimodality in warning displays are not well understood. One potential hypothesis that has recently received support in the avian literature (but has yet to be examined in invertebrates) is that different signal components may interact synergistically, such that one component of a signal (odor) may trigger a predator’s aversion to another component of a signal (color). Here, we gave jumping spiders (Habronattus trimaculatus) the choice between red or black prey (artificially colored termites) in either the presence or absence of odor from the chemically defended coreid bug (Acanthocephala femorata). When the odor was present, spiders were more likely to avoid the color red compared with when the odor was absent. Interestingly, this pattern only held up when the odor was novel; subsequent exposure to the odor had no effect on color preference. Moreover, this pattern only held for the color red (a color typically used as a warning color and often paired with odor). We replicated this experiment giving spiders the choice between green or black prey, and found that the presence of the odor had no effect on the spiders’ responses to the color green. We discuss these findings in the context of predator psychology and the evolution of prey coloration.

Multimodal warning displays often pair one signal modality (odor) with a second modality (color) to avoid predation. Experiments with bird predators suggest these signal components interact synergistically, with aversive odors triggering otherwise hidden aversions to particular prey colors. In a recent study, this phenomenon was found in a jumping spider (Habronattus trimaculatus), with the defensive odor from a coreid bug (Acanthocephala femorata) triggering an aversion to red. Here, we explore how generalizable this phenomenon is by giving H. trimaculatus the choice between red or black prey in the presence or absence of defensive odors secreted from (1) eastern leaf-footed bugs (Leptoglossus phyllopus, Hemiptera), (2) grass stinkbugs (Mormidea pama, Hemiptera), (3) Asian ladybird beetles (Harmonia axyridis, Coleoptera), and (4) eastern lubber grasshoppers (Romalea microptera, Orthoptera). As expected, in the presence of the hemipteran odors, spiders were less likely to attack red prey (compared to no odor). Unexpectedly, the beetle and grasshopper odors did not bias spiders away from red. Our results with the hemipteran odors were unique to red; follow-up experiments indicated that these odors did not affect biases for/against green prey. We discuss our findings in the context of generalized predator foraging behavior and the functions of multimodal warning displays.

Stable between‐group differences in collective behavior have been documented in a variety of social taxa. Here we evaluate the effects of such variation, often termed collective or colony‐level personality, on coral recovery in a tropical marine farmerfish system. Groups of the farmerfish Stegastes nigricans cultivate and defend gardens of palatable algae on coral reefs in the Indo‐Pacific. These gardens can promote the recruitment, growth, and survival of corals by providing a refuge from coral predation. Here we experimentally evaluate whether the collective response of farmerfish colonies is correlated across intruder feeding guilds – herbivores, corallivores and egg‐eating predators. Further, we evaluate if overall colony responsiveness or situation‐specific responsiveness (i.e. towards herbivores, corallivores, or egg‐eaters in particular) best predicts the growth of outplanted corals. Finally, we experimentally manipulated communities within S. nigricans gardens, adding either macroalgae or large colonies of coral, to assess if farmerfish behavior changes in response to the communities they occupy. Between‐group differences in collective responsiveness were repeatable across intruder guilds. Despite this consistency, responsiveness towards corallivores (porcupinefish and ornate butterflyfish) was a better predictor of outplanted coral growth than responsiveness towards herbivores or egg‐eaters. Adding large corals to farmerfish gardens increased farmerfish attacks towards intruders, pointing to possible positive feedback loops between their aggression towards intruders and the presence of corals whose growth they facilitate. These data provide evidence that among‐group behavioral variation could strongly influence the ecological properties of whole communities.

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Phidippus audax (Hentz 1845), a common North American jumping spider, is a visual predator that uses its highly developed eyesight to detect and forage actively for prey. We demonstrate that P. audax can survive throughout its life cycle as a scavenger. We separated 600 spiderlings into eight treatments examining all combinations of three different variables: live versus dead prey, substrate present versus substrate absent, and large versus small arenas. Over the course of the study, we recorded survival rates, instar durations, and carapace widths. Our results indicate that P. audax can survive solely on a diet of dead prey, but at significantly lower survival rates and with longer instar durations than spiders fed on live prey. Scavenging spiders, however, exhibited no significant difference in carapace widths when compared to predators. Choice tests conducted on adults indicate that spiders raised as either predators or scavengers exhibit no significant differences in prey choice when given the option of live or dead prey.

Chemically defended prey often advertise their toxins with bright and conspicuous colors. To understand why such colors are effective at reducing predation, we need to understand the psychology of key predators. In bird predators, there is evidence that individuals avoid novelty—including prey of novel colors (with which they have had no prior experience). Moreover, the effect of novelty is sometimes strongest for colors that are typically associated with aposematic prey (e.g., red, orange, yellow). Given these findings in the bird literature, color neophobia has been argued to be a driving force in the evolution of aposematism. However, no studies have yet asked whether invertebrate predators respond similarly to novel colors. Here, we tested whether naive lab-raised jumping spiders (Habronattus pyrrithrix) exhibit similar patterns of color neophobia to birds. Using color-manipulated living prey, we first color-exposed spiders to prey of two out of three colors (blue, green, or red), with the third color remaining novel. After this color exposure phase, we gave the spiders tests where they could choose between all three colors (two familiar, one novel). We found that H. pyrrithrix attacked novel and familiar-colored prey at equal rates with no evidence that the degree of neophobia varied by color. Moreover, we found no evidence that either prey novelty nor color (nor their interaction) had an effect on how quickly prey was attacked. We discuss these findings in the context of what is known about color neophobia in other animals and how this contributes to our understanding of aposematic signals.

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