Alarm calls of sagebrush converge when herbivory is high.

Herbivory is a major threat to virtually all plants, so adaptations to avoid herbivory will generally be selected. One potential adaptation is the ability to 'listen in' on the volatile cues emitted by plants that are experiencing herbivory and to then respond by ramping up defences. The nature of these volatile cues is poorly understood.

Spatial habitat heterogeneity influences host-pathogen dynamics in a patchy population of Ranchman's tiger moth.

Host-pathogen dynamics are influenced by many factors that vary locally, but models of disease rarely consider dynamics across spatially heterogeneous environments. In addition, theory predicts that dispersal will influence host-pathogen dynamics of populations that are linked, although this has not been examined empirically in natural systems. We examined the spatial dynamics of a patchy population of tiger moths and its baculovirus pathogen, in which habitat type and weather influence dynamics.

The consequence of leaf life span to virus infection of herbivorous insects.

Many herbivorous insects die of pathogen infections, though the role of plant traits in promoting the persistence of these pathogens as an indirect interaction is poorly understood. We tested whether winter leaf retention of bush lupines (Lupinus arboreus) promotes the persistence of a nucleopolyhedroviruses, thereby increasing the infection risk of caterpillars (Arctia virginalis) feeding on the foliage during spring. We also investigated whether winter leaf retention reduces viral exposure of younger caterpillars that live on the ground, as leaf retention prevents contaminated leaves from reaching the ground.

Flowers that self-shade reduce heat stress and pollen limitation.

Premise: Plants are facing increased risk of heat stress with global climate change. Reproductive tissues are particularly heat-sensitive, which can result in lower plant fitness. Floral shading and closure are possible mechanisms to limit heat stress although most previous work on petal orientation has considered adaptations to raise temperatures.

Hilltopping influences spatial dynamics in a patchy population of tiger moths.

Dispersal is a key driver of spatial population dynamics. Dispersal behaviour may be shaped by many factors, such as mate-finding, the spatial distribution of resources, or wind and currents, yet most models of spatial dynamics assume random dispersal. We examined the spatial dynamics of a day-flying moth species () that forms mating aggregations on hilltops (hilltopping) based on long-term adult and larval population censuses.

Plant induced defenses that promote cannibalism reduce herbivory as effectively as highly pathogenic herbivore pathogens.

Plant induced defenses may benefit plants by increasing cannibalism among insect herbivores. However, the general efficacy of plant defenses that promote cannibalism remains unclear. Using a generalist Lepidopteran herbivore (Helicoverpa zea), we examined whether plant induced defenses in Solanum lycopersicum increased cannibalism among H.

Consistent individual variation in plant communication: do plants have personalities?

Animal biologists have recently focused on individual variation in behavioral traits and have found that individuals of many species have personalities. These are defined as consistent intraspecific differences in behaviors that are repeatable across different situations and stable over time. When animals sense danger, some individuals will alert neighbors with alarm calls and both calling and responding vary consistently among individuals.

Risk of herbivory negatively correlates with the diversity of volatile emissions involved in plant communication.

Plant-to-plant volatile-mediated communication and subsequent induced resistance to insect herbivores is common. Less clear is the adaptive significance of these interactions; what selective mechanisms favour plant communication and what conditions allow individuals to benefit by both emitting and responding to cues? We explored the predictions of two non-exclusive hypotheses to explain why plants might emit cues, the kin selection hypothesis (KSH) and the mutual benefit hypothesis (MBH). We examined 15 populations of sagebrush that experience a range of naturally occurring herbivory along a 300 km latitudinal transect.

Advances in the Evolution and Ecology of 13- and 17-Year Periodical Cicadas.

Apart from model organisms, 13- and 17-year periodical cicadas (Hemiptera: Cicadidae: ) are among the most studied insects in evolution and ecology. They are attractive subjects because they predictably emerge in large numbers; have a complex biogeography shaped by both spatial and temporal isolation; and include three largely sympatric, parallel species groups that are, in a sense, evolutionary replicates. are also relatively easy to capture and manipulate, and their spectacular, synchronized mass emergences facilitate outreach and citizen science opportunities.

Loss of branches due to winter storms could favor deciduousness in oaks.

Premise: Ecologists have an incomplete understanding of the factors that select for deciduous, evergreen, and marcescent leaf habits. Evergreens have more opportunities for photosynthesis but may experience costs when abiotic conditions are unfavorable such as during ice and windstorms.

Methods: We documented branch loss for species of oaks (Quercus spp.

Altered precipitation dynamics lead to a shift in herbivore dynamical regime.

The interaction between endogenous dynamics and exogenous environmental variation is central to population dynamics. Although investigations into the effects of changing mean climate are widespread, changing patterns of variation in environmental forcing also affect dynamics in complex ways. Using wavelet and time series analyses, we identify a regime shift in the dynamics of a moth species in California from shorter to longer period oscillations over a 34-year census, and contemporaneous changes in regional precipitation dynamics.

Effects of experimental watering but not warming on herbivory vary across a gradient of precipitation.

Climate change can affect biotic interactions, and the impacts of climate on biotic interactions may vary across climate gradients. Climate affects biotic interactions through multiple drivers, although few studies have investigated multiple climate drivers in experiments. We examined the effects of experimental watering, warming, and predator access on leaf water content and herbivory rates of woolly bear caterpillars () on a native perennial plant, pacific silverweed (), at two sites across a gradient of precipitation in coastal California.

Proportional fitness loss and the timing of defensive investment: a cohesive framework across animals and plants.

The risk of consumption is a pervasive aspect of ecology and recent work has focused on synthesis of consumer-resource interactions (e.g., enemy-victim ecology).

Feeding and damage-induced volatile cues make beetles disperse and produce a more even distribution of damage for sagebrush.

Induced plant responses to herbivory are common, and we have learned a lot about the mechanisms of induced resistance and their effects on herbivore performance. We know less about their effects on herbivore behaviour and especially on spatial patterns of damage. Theoretical models predict that induced responses can cause patterns of damage to become aggregated, random or even.

Induction of the sticky plant defense syndrome in wild tobacco.

Many plants engage in protective mutualisms, offering resources such as extrafloral nectar and shelters to predatory arthropods in exchange for protection against herbivores. Recent work indicates that sticky plants catch small insects and provide this carrion to predators who defend the plants against herbivores. In this study, we investigated whether wild tobacco, Nicotiana attenuata, fits this sticky plant defense syndrome that has been described for other sticky plants.

The effects of pulsed fertilization and chronic herbivory by periodical cicadas on tree growth.

Although many studies have investigated plant growth in the context of episodic herbivory and pressed resource availability, relatively few have examined how plant growth is affected by pulsed resources and chronic herbivory. Periodical cicada (Magicicada spp.) adults represent a pulsed detrital subsidy that fertilizes plants, and live cicada nymphs are long-lived root-feeding herbivores.

Unidirectional grass hairs usher insects away from meristems.

Grasses are major agricultural products worldwide and they are critical to ecosystem function in many terrestrial habitats. Despite their global importance, we know relatively little about their defenses against herbivory. Grasses tend to be tolerant of leaf loss because their valuable meristems are located underground, out of reach for above ground herbivores.

A judgment and decision-making model for plant behavior.

Recently plant biologists have documented that plants, like animals, engage in many activities that can be considered as behaviors, although plant biologists currently lack a conceptual framework to understand these processes. Borrowing the well-established framework developed by psychologists, we propose that plant behaviors can be constructively modeled by identifying four distinct components: (1) a cue or stimulus that provides information, (2) a judgment whereby the plant perceives and processes this informative cue, (3) a decision whereby the plant chooses among several options based on their relative costs and benefits, and (4) action. Judgment for plants can be determined empirically by monitoring signaling associated with electrical, calcium, or hormonal fluxes.

As temperature increases, predator attack rate is more important to survival than a smaller window of prey vulnerability.

Climate change can have strong effects on species interactions and community structure. Temperature-dependent effects on predator-prey interactions are a major mechanism through which these effects occur. To understand the net effects of predator attack rates and dynamic windows of prey vulnerability, we examined the impacts of temperature on the interaction of a caterpillar (Arctia virginalis) and its ant predator (Formica lasioides).

Wet years have more caterpillars: interacting roles of plant litter and predation by ants.

Climate is widely recognized as an important factor that affects temporal and spatial patterns of occurrence and abundance of herbivorous insects, although the ecological mechanisms responsible are poorly understood. We found that precipitation and standing water were positively correlated with locations and years of high abundance of caterpillars of the ranchman's tiger moth, Platyprepia virginalis. We analyzed 30 years of survey data and found that the number of large rainfall events was a better predictor of caterpillar abundance than total annual accumulation.

Tradeoff between resistance induced by volatile communication and over-topping vertical growth.

Plants commonly respond to reliable cues about herbivores by inducing greater defenses. Defenses are assumed to incur costs for plants when they are not needed. Sagebrush responds to volatile cues from experimentally clipped neighbors to induce resistance against chewing herbivores.