Periodical Cicadas Research Articles

Periodical Cicadas as Resource Pulses in North American Forests

Resource pulses are occasional events of ephemeral resource superabundance that occur in many ecosystems. Aboveground consumers in diverse communities often respond strongly to resource pulses, but few studies have investigated the belowground consequences of resource pulses in natural ecosystems. This study shows that resource pulses of 17-year periodical cicadas (Magicicada spp.) directly increase microbial biomass and nitrogen availability in forest soils, with indirect effects on growth and reproduction in forest plants. These findings suggest that pulses of periodical cicadas create "bottom-up cascades," resulting in strong and reciprocal links between the aboveground and belowground components of a North American forest ecosystem.

Asymmetry and Mating Success in a Periodical Cicada, Magicicada septendecim (Hemiptera: Cicadidae)

AbstractPhenotypic symmetry results from both a genetic predisposition and the influence of the developmental environment. Although most studies of mate choice and phenotypic asymmetry are couched in terms of active choice for ‘good genes’, an alternative viewpoint is to consider incidental mating biases that arise from the functional effects of asymmetrical phenotypes. This paper (i) discusses the specific situations in which symmetry‐based mate choice may be likely, and (ii) presents research on female mate choice and symmetry in the periodical cicada, Magicicada septendecim (L.). Male mating aggregations and lack of mating gifts or parental care make this species an ideal target for studying female choice for superior mates, and thus for a relationship between male symmetry and male mating success.

THE HISTORICAL CONTRACTION OF PERIODICAL CICADA BROOD VII (HEMIPTERA: CICADIDAE: MAGICICADA)

We discuss periodical cicada (Magicicada) Brood VII, which is becoming extinct from much of its historically-reported range in upstate New York. During searches in June of 2001, we found Magicicada adults in only 10 of 37 sites (and two of eight counties) where periodical cicadas had been reported previously, and dense populations were restricted to a small region south of Syracuse and centered on the Onondaga Nation. We suggest possible explanations, including land clearing and climate change, for the decline of this brood and the extinction of other Magicicada broods.

Thresholds or Comparisons: Mate Choice Criteria And Sexual Selection in a Periodical Cicada, Magicicada Septendecim (Hemiptera: Cicadidae)

AbstractMany insects possess life history characteristics that make them unlikely to use the kinds of relative mate choice criteria implicit in theoretical discussions of leks; thus, many insect mating aggregations are treated differently, as 'swarms' or 'choruses.' Yet periodical cicadas (Magicicada spp.) seem strong candidates for participating in lek mating systems. We present a series of observations and experiments designed to reveal whether there are mating biases in periodical cicadas and whether any biases are most consistent with flexible ('best-of-N 'choice) or fixed (threshold choice) mating criteria. We rule out postcopulatory choice by demonstrating that most females mate once, after which they become sexually unreceptive. In our study, patterns of mating success among actively chorusing males are indistinguishable from random mating, and we uncover no consistent differences between unmated and mated males on the basis of size and song pitch, two criteria that have been associated with Magicicada mating biases in other contexts. Because our results are most consistent with a fixed-threshold choice mechanism, we suggest that Magicicada mating aggregations do not function in a manner similar to vertebrate leks even though they fulfill Bradbury's (1981) lek criteria. Instead, features of Magicicada behavior suggesting female selectivity may arise incidentally from males' and females' unequal tendencies to mate multiply, the resulting superabundance of sexually receptive males, and the high frequency at which females are courted at the onset of mating readiness.

Bugs That Count

Along the East Coast of the United States, a cohort of periodical cicadas known as Brood X occupies the prime turf from New York City down to Washington, D.C. Brood Xers are the hip, urban cicadas, the inside-the Beltway cicadas, the media-savvy celebrity cica das. When they emerge from their underground existence every 17 years, they face predatory flocks of science writers and television crews, hungry for a story. This year was a Brood X year. Back in May and June, all along the Metroliner corridor, the air was abuzz with cicada calls, echoed and am plified by the attentive journalists. Then, in just a few weeks, it was all over. The cicadas paired off, fell silent, laid eggs and died. The press moved on to the next sensation. Perhaps a few straggler cicadas showed up days or weeks late, but no one was there to notice, and their prospects can not have been bright. I worry that the same fate may befall an article about cicadas appearing weeks after the great emergence, at the very mo ment when most of us want to hear not another

Regional impacts of periodical cicadas on oak radial increment

We investigated the effects of periodical cicadas (Magicicada spp.) on growth of their hosts using records of radial tree-ring growth on oaks (Quercus spp., a common host genus) and pines (Pinus spp., a common nonhost genus) growing within the ranges of 13- and 17-year broods. Growth of oaks was significantly depressed during years of adult emergence by about 4%. Effects in years following emergences or in years prior to emergences were variable or absent. Spectral analyses revealed a significant tendency for periodicity in the growth of oaks, but not pines, matching that of the life cycle of the broods. These results provide some of the first evidence for landscape-level effects of a root-feeding insect and demonstrate that periodical cicadas have a small but detectable effect on growth of their hosts on a geographical scale, considerably larger than previously suspected.

A COMMENT ON GENE INTROGRESSION VERSUS EN MASSE CYCLE SWITCHING IN THE EVOLUTION OF 13-YEAR AND 17-YEAR LIFE CYCLES IN PERIODICAL CICADAS

In companion papers, Simon et al. (2000) and Marshall and Cooley (2000) discuss geographic distributions of phenotypic characters and genetic markers of Magicicada decim spp. in the lower Mississippi valley and vicinity. Periodical cicadas (Magicicada spp.) of eastern North America have spurred many debates concerning the evolutionary origin of their unusual 13-year and 17-year life cycles, and instantaneous speciation through en masse cycle switching has been a recurring hypothesis. En masse switching both from 13to 17-year cycles and from 17to 13-year cycles are components of the cycle-switching model of Magicicada evolution (e.g., Lloyd and Dybas 1966a, 1966b; Lloyd and White 1976; Simon 1979, 1988; Martin and Simon 1988, 1990; Williams and Simon 1995). The new field data of Marshall and Cooley (2000) document character displacement between 13-year cicadas with genotypes similar to northern 17-year populations, and sympatric 13-year cicadas with genotypes similar to southern 13-year populations. Simon et al. (2000) interpret this character displacement and other new genetic data as support for the hypothesis of instantaneous speciation by en masse cycle switching from 17to 13-year cycles. However, it is our view that these authors do not adequately explore conventional gene flow explanations of the observed phenotypic and genetic variation that do not require en masse cycle switching. Evaluation of these competing hypotheses can benefit from an interdisciplinary perspective incorporating paleoecological data. We (Cox and Carlton 1988, 1991, 1998; Cox 1992) previously proposed an alternative selection-gene introgression model for Magicicada evolution incorporating paleoecological reconstructions that also explains these new genetic and phenotypic observations of Simon et al. (2000) and Marshall and Cooley (2000). Our hypothesis offers an important caveat about the use of mtDNA in certain circumstances to interpret the magnitude of gene flow between populations and evolutionary processes. We hypothesize unidirectional gene flow via dispersing male cicadas that transferred limited nuclear DNA and no mtDNA to the recipient population. In brief, our model presented in Cox and Carlton (1988) proposes that life-cycle timing differences between cicada populations arose not from en masse cycle switching, but from stochastic selection processes involving Magicicada temperature thresholds, Pleistocene climate characteristics, and hybridization frequencies between populations having a spectrum of life-cycle lengths. Heath (1967, 1968) reports that periodical cicadas emerge from their burrows when soil temperature is 64.3?F and that the air temperature must reach 68?F for flight and mating. In our quantitative model, during glacial maximum it was much more common than it is now for summers to remain too cold for ancestral periodical cicadas to emerge and/or mate, and the ancestors of periodical cicada populations must have failed to reproduce during those years. This seasonal capriciousness gave rise to periodicity (years without cicadas) and selection of long life cycles (conferring a reduced chance of emerging on a cool summer). By the parameters of our model, selected life cycles would be ? 12 years and would be longer in colder climates. This aspect of our model explains the climatically correlated zonation of Magicicada life cycles (Fig. 1). Once periodicity and long life cycles were established, satiation of predators by synchronized emergence became an important strategy for periodical cicadas. Predator satiation works best with precisely synchronized periodicity, and cycle synchronization is diminished by increased heterozygosity. Thus, cicadas that are hybrids of two populations with different cycle lengths will suffer greater predation losses, as many may emerge on years before or after the main population. Cicadas with prime-numbered cycles (13 years and 17 years) will hybridize significantly less frequently than cicadas with non-prime (composite) cycles and thus will have larger emergences and a greater advantage of predator satiation. See Cox and Carlton (1988) for a full discussion of this topic. Marshall and Cooley (2000) studied M. decim spp. of southern 13-year Brood XIX (each brood consists of all synchronized individuals) within the contact zone with more northern 17-year broods (M. septendecim). These authors document character displacement of call pitch between male 13year cicadas with abdominal coloration like cicadas of contiguous 17-year populations (new 13-year cicadas, M. neotredecim) and sympatric male 13-year cicadas with coloration like contiguous Brood XIX populations in the lower Mississippi valley (old 13-year cicadas, M. tredecim). Marshall and Cooley (2000, see their Figs. 4 and 9) argue that M. tredecim have never been present within the range M. neotredecim north of the contact zone and that these two species have hybridized only along the contact zone at the southern margin of the M. neotredecim range. The steep gradient in call pitch frequency along the southern margin of M. neo-

HOLOCENE CLIMATE SHIFTS, LIFE-CYCLE PLASTICITY, AND SPECIATION IN PERIODICAL CICADAS: A REPLY TO COX AND CARLTON

Journal Article HOLOCENE CLIMATE SHIFTS, LIFE‐CYCLE PLASTICITY, AND SPECIATION IN PERIODICAL CICADAS: A REPLY TO COX AND CARLTON Get access David C. Marshall, David C. Marshall Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Storrs, Connecticut 06269‐3043 E‐mail: david.marshall@uconn.edu Search for other works by this author on: Oxford Academic Google Scholar John R. Cooley, John R. Cooley Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Storrs, Connecticut 06269‐3043 E‐mail: jcooley@sp.uconn.eduDepartment of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Storrs, Connecticut 06269‐3043 E‐mail: david.marshall@uconn.edu Search for other works by this author on: Oxford Academic Google Scholar Chris Simon Chris Simon Department of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Storrs, Connecticut 06269‐3043 E‐mail: csimon@uconnvm.uconn.eduDepartment of Ecology and Evolutionary Biology, University of Connecticut, 75 N. Eagleville Road, Storrs, Connecticut 06269‐3043 E‐mail: david.marshall@uconn.edu Search for other works by this author on: Oxford Academic Google Scholar Evolution, Volume 57, Issue 2, 1 February 2003, Pages 433–437, https://doi.org/10.1111/j.0014-3820.2003.tb00277.x Published: 01 February 2003 Article history Received: 23 October 2002 Accepted: 20 November 2002 Published: 01 February 2003

HOLOCENE CLIMATE SHIFTS, LIFE-CYCLE PLASTICITY, AND SPECIATION IN PERIODICAL CICADAS: A REPLY TO COX AND CARLTON

HOLOCENE CLIMATE SHIFTS, LIFE-CYCLE PLASTICITY, AND SPECIATION IN PERIODICAL CICADAS: A REPLY TO COX AND CARLTON

Temporal Separation and Speciation in Periodical Cicadas

Abstract Speciation, the set of processes by which two populations of one species become distinct species, is an important topic in evolutionary biology. It is usually impractical to conduct experiments on how new species form, but occasionally the natural history of a species places it in a context that may be thought of as a “natural experiment” with regard to speciation. One such natural experiment involves the periodical cicadas of eastern North America, a group in which populations have become isolated in time and space. Some of these isolated populations appear to have evolved into distinct genetic lineages. A rare life-cycle switching event brought two such lineages into contact in the relatively recent past, and the two lineages are now behaving as distinct species. This natural experiment provides important insights into species differences and the processes that underlie species formation.

Infectivity of resting spores of Massospora cicadina (Entomophthorales: Entomophthoraceae), an entomopathogenic fungus of periodical cicadas (Magicicada spp.) (Homoptera: Cicadidae).

Massospora cicadina Peck is a fungal pathogen of 13- and 17-year periodical cicadas (Magicicada spp.). In northwest Arkansas, during the spring 1998 emergence of the 13-year periodical cicada, Magicicada tredecassini (Brood XIX), <1% of emerging cicadas were infected with the conidial stage of M. cicadina, similar to data collected from the same population in 1985. However, in northwest Arkansas plots treated with M. cicadina resting spores collected from infected 17-year Magicicada septendecim cicadas (Brood IV) in 1997 from southern Iowa, 10 months prior to the 1998 emergence in Arkansas, conidial stage infections of M. cicadina in 13-year Arkansas M. tredecassini cicadas increased significantly to 10.6% (7.9% in males and 2.6% in females). These data suggest that M. cicadina resting spores do not require a dormancy of 13 or 17 years between cicada emergences. Instead M. cicadina resting spores appear to be capable of germinating and infecting periodical cicadas after less than 1 year. In addition, M. cicadina resting spores derived from one species (17-year M. septendecim cicadas) were infective for a second species (13-year M. tredecassini cicadas). A mean of 1.4 x 10(6)(SE = 1.8 x 10(5)) mature resting spores were produced per infected male M. septendecim.

Periodical Cicada (Magicicada cassini) Oviposition Damage: Visually Impressive yet Dynamically Irrelevant

Abstract Selective herbivory by animals can have significant effects on the succession of a plant community. Damage resulting from major insect outbreaks has been shown to alter species dominance and competitive balance of woody plants in temperate North America. In this study we examine the effects over three seasons of a visually striking herbivory event: periodical cicada (Magicicada cassini) oviposition into an early successional tree community in the prairie-forest ecotone in eastern Kansas. Oviposition damage during cicada emergence in 1998 was large in overall magnitude, highly variable in space and varied by host tree species. From 1998–2000 we monitored four measures of tree growth on individuals of each tree species on the study site, and infructescence production on the dominant species (rough leaved dogwood, Cornus drummondii). Cicada damage in 1998 was regressed against each measure of tree performance in following years. Only a few statistically significant results were found. Overall, we co...

Long-range Acoustical Signals, Phonotaxis, and Risk in the Sexual Pair-Forming Behaviors of &lt;I&gt;Okanagana canadensis&lt;/I&gt; and &lt;I&gt;O. rimosa&lt;/I&gt; (Hemiptera: Cicadidae)

The sexual behaviors of Okanagana canadensis (Provancher) and O. rimosa (Say) are described. In northern Michigan, O. canadensis is typically found in coniferous vegetation, such as cedars; whereas O. rimosa frequent deciduous vegetation. In both species, males call from stationary perches, and females approach them. Females have no specialized receptivity signals, but both males and females engage in bouts of wing flicking that may be alternative, low-risk signaling. Mating is brief and involves no elaborate courtship. The Okanagana mating system, characterized by male advertisement and female searching, is contrasted with that of Magicicada spp., the periodical cicadas of North America, and discussed in the context of relative risks of signaling and searching behaviors.

Phylogeography of the New Zealand cicada Maoricicada campbelli based on mitochondrial DNA sequences: ancient clades associated with cenozoic environmental change.

New Zealand's isolation, its well-studied rapidly changing landscape, and its many examples of rampant speciation make it an excellent location for studying the process of genetic differentiation. Using 1520 base pairs of mitochondrial DNA from the cytochrome oxidase subunit I, ATPase subunits 6 and 8 and tRNA(Asp) genes, we detected two well-differentiated, parapatrically distributed clades within the widespread New Zealand cicada species Maoricicada campbelli that may prove to represent two species. The situation that we uncovered is unusual in that an ancient lineage with low genetic diversity is surrounded on three sides by two recently diverged lineages. Using a relaxed molecular clock model coupled with Bayesian statistics, we dated the earliest divergence within M. campbelli at 2.3 +/- 0.55 million years. Our data suggest that geological and climatological events of the late Pliocene divided a once-widespread species into northern and southern components and that near the middle of the Pleistocene the northern lineage began moving south eventually reaching the southern clade. The southern clade seems to have moved northward to only a limited extent. We discovered five potential zones of secondary contact through mountain passes that will be examined in future work. We predict that, as in North American periodical cicadas, contact between these highly differentiated lineages will exist but will not involve gene flow.

Periodical Cicada (Homoptera: Cicadidae) Life-Cycle Variations, the Historical Emergence Record, and the Geographic Stability of Brood Distributions

The complex biogeography of the 13- and 17-yr periodical cicadas offers important opportunities for testing hypotheses of Magicicada evolution and ecology. However, misinterpretation of stragglers as on-schedule emergences, combined with systematic biases in search effort and the use of cross-generational brood maps, likely results in erroneous edge extension of adjacent broods and the appearance of sympatric shadow broods in published maps. Substantial recent changes in brood distributions have been inferred from the Magicicada historical record, the most significant being the decline and extinction of 17-yr brood X in the midwestern United States, the widespread expansion and contraction of 17-yr brood VI and 13-yr brood XXIII, and the displacement of brood XIII 17-yr cicadas in Illinois by 13-yr brood XIX in Illinois. Reanalysis of the historical data with an awareness of straggler-induced error suggests instead that brood distributions in these cases have remained stable.

Allochronic speciation, secondary contact, and reproductive character displacement in periodical cicadas (Hemiptera: Magicicada spp.): genetic, morphological, and behavioural evidence.

Periodical cicadas have proven useful in testing a variety of ecological and evolutionary hypotheses because of their unusual life history, extraordinary abundance, and wide geographical range. Periodical cicadas provide the best examples of synchronous periodicity and predator satiation in the animal kingdom, and are excellent illustrations of habitat partitioning (by the three morphologically distinct species groups), incipient species (the year classes or broods), and cryptic species (a newly discovered 13-year species, Magicicada neotredecim). They are particularly useful for exploring questions regarding speciation via temporal isolation, or allochronic speciation. Recently, data were presented that provided strong support for an instance of allochronic speciation by life-cycle switching. This speciation event resulted in the formation of a new 13-year species from a 17-year species and led to secondary contact between two formerly separated lineages, one represented by the new 13-year cicadas (and their 17-year ancestors), and the other represented by the pre-existing 13-year cicadas. Allozyme frequency data, mitochondrial DNA (mtDNA), and abdominal colour were shown to be correlated genetic markers supporting the life-cycle switching/allochronic speciation hypothesis. In addition, a striking pattern of reproductive character displacement in male call pitch and female pitch preference between the two 13-year species was discovered. In this paper we report a strong association between calling song pitch and mtDNA haplotype for 101 individuals from a single locality within the M. tredecim/M. neotredecim contact zone and a strong association between abdomen colour and mtDNA haplotype. We conclude by reviewing proposed mechanisms for allochronic speciation and reproductive character displacement.

Spatial variability in oviposition damage by periodical cicadas in a fragmented landscape.

Effects of the periodical cicada (Magicicada spp.) on forest dynamics are poorly documented. A 1998 emergence of M. cassini in eastern Kansas led to colonization of a fragmented experimental landscape undergoing secondary succession. We hypothesized that per-tree rates of oviposition damage by cicadas would reflect: (1) distance from the source of the emergence, (2) patch size, and (3) local tree density. Ovipositing females displayed clear preferences for host species and damage incidence showed predictable spatial patterns. Two species (smooth sumac, Rhus glabra, and eastern red cedar, Juniperus virginiana) were rarely attacked, whereas others (rough-leaved dogwood, Cornus drummondii; slippery elm, Ulmus rubra; box elder, Acer negundo, and honey locust, Gleditsia triacanthos) were strongly attacked. The dominant early successional tree, dogwood, received on average the most attacks. As predicted, attacks per stem declined strongly with distance from the emergence source, and with local stem density (a "dilution" effect). Contrary to expectations, there were more attacks per stem on larger patches. Because ovipositing cicadas cut damaging slits in host tree branches, potentially affecting tree growth rate, competitive ability, and capacity to reproduce, cicada damage could potentially influence spatial variation in secondary succession.

Emergence of Periodical Cicadas (Magicicada cassini) From a Kansas Riparian Forest: Densities, Biomass and Nitrogen Flux

The 1998 emergence of 17-y periodical cicadas (Magicicada cassini) on Konza Prairie Research Natural Area (KPRNA), Kansas, was quantified using emergence trap transects and counts of emergence holes. Emergence density, biomass (emergence production) and associated nitrogen flux were estimated for the entire 100 ha gallery forest of Kings Creek, the major drainage network on KPRNA. Emergence commenced on 22 May 1998 and lasted for 24 d, with 87% of the individuals emerging within the first 9 d. Males dominated early during the emergence, and the sex ratio for the entire population was estimated at 54:46 male:female. Average emergence abundance and biomass estimated from trap transects located in low areas where cicadas were most abundant were 152/m2 and 34.9 g ash-free dry mass (AFDM)/m2, respectively. Based on emergence hole counts, average density and biomass for the 59 ha of gallery forest where cicadas emerged were 27.2 individuals/m2 and 6.3 g AFDM/m2, and emergence hole densities >100/m2 were evident in low areas of the drainage. Emergence density generally decreased with increasing elevation in the catchment. Belowground to aboveground N flux associated with M. cassini emergence in high density areas was ∼3 g N/m2, and the average for the entire emergence area was 0.63 g N/m2. The total number of individuals that emerged from the Kings Creek riparian forest was estimated at 19.6 million, which represents 4.6 metric tons AFDM and ∼0.5 metric tons N. This linear, fragmented, gallery forest of the Flint Hills supports a high density of M. cassini, and an emergence event constitutes a significant belowground to aboveground flux of energy and nutrients. Thus, the periodical cicada may be an exception to the notion that insects generally do not represent important resource pools at the ecosystem level.

Sexual Signaling in Periodical Cicadas, Magicicada spp. (Hemiptera: Cicadidae)

Periodical cicada ( Magicicada spp.) sexual pair formation takes place in dense aggregations and involves intense male-male competition for limited mating opportunities. Pair-forming behavior in these species has been poorly understood because of limited knowledge of sexual communication. We have found that sexually receptive female Magicicada flick their wings in timed response to an individual chorusing male; this previously unrecognized female response is hereafter referred to as a 'wing-flick' signal. We document the nature, timing, and species-specificity of this signal as well as its absence in both immature and mated females. We also document changes in male chorusing and searching behavior in response to wing-flick signals and male responses to the signals' visual and acoustical components. We test the hypothesis that female sensory psychology has shaped the evolution of-decim calls by favoring frequency-modulated male calls that are more readily distinguishable in an intense background chorus. Within mating aggregations, male Magicicada attempt to usurp ongoing courtships and also engage in interference competition by acoustically obscuring the calls of potential interlopers, reducing the likelihood of a female response.

The prime number periodical cicada problem

Mathematical models are presented to argue for the significance of prime number emergences of 13 year and 17 year periodical cicadas (Magicicada spp.). The prime number values arise as resonances of emergences with 2 and 3 year quasi-cycling predators. Predators with 2 and 3 year quasi-cycles are present due to their age dependent fecundity and mortality rates. Their quasi-cycles are enhanced by the predation of cicadas during emergences and thus exert significant influence on the cicada periodic life cycles.