The Distribution of Periodical Cicada (Hemiptera: Cicadidae:Magicicada) Brood II in 2013: Disjunct Emergences Suggest Complex Brood Origins

The periodical cicada four-year acceleration hypothesis revisited and the polyphyletic nature of Brood V, including an updated crowd-source enhanced map (Hemiptera: Cicadidae: Magicicada)

“… Orange symbols are verified positive records; gray symbols are verified negative records. Brood II presence records are shown in red and reprinted from Cooley et al (2015) . …”

“…We used these records to inform our decisions about areas to map in detail. Individual crowdsourced records are not necessarily reliable; thus, we weighted crowdsourced records by assigning higher confidence to records that were clustered or that were in close proximity to verified records as described in Cooley et al (2015) . After we had stopped collecting data from the general public, we received an unusual number of reports from Carbon County, Pennsylvania, via the website http://www.cicadamania.com/ which we then investigated.…”

“…1 ; see also Lloyd & White, 1976 ; Simon, 1983 ). The discovery of persistent disjunct “miniature” brood isolates on Long Island, New York and elsewhere ( Simon & Lloyd, 1982 ; Cooley, 2015 ; Cooley et al, 2015 ) and genetic evidence that many broods have complex, multiple origins ( Martin & Simon, 1988 ; Martin & Simon, 1990 ; Simon et al, 2000 ; Cooley et al, 2001 ; Sota et al, 2013 ) suggest that the process modeled by this hypothesis, in which populations become temporally isolated and form new broods or join existing ones, may be more common than previously thought and apply to more than just the known disjunct populations. Here we test whether the main body of Brood V has a single origin, or whether it reflects multiple episodes of brood formation.…”

Peer Review #2 of "The periodical cicada four-year acceleration hypothesis revisited and the polyphyletic nature of Brood V, including an updated crowd-source enhanced map (Hemiptera: Cicadidae: Magicicada) (v0.1)"

“…While a four-year jump model can account for the timing and geography of the Long Manuscript to be reviewed origin of populations of Brood II in eastern Oklahoma, found occupying a gap within Brood IV (Cooley et al 2015).…”

“…In one scenario, the These scenarios, involving either a Brood XIV or a Brood II ancestor, each require at least one four-year deceleration. Of these scenarios, a Brood II ancestor seems more plausible because a) no populations of Brood XIV are currently found nearby(Cooley et al 2011), and b) present-day Carbon County Brood V populations are encircled by Brood II(Cooley et al 2015). However, all of these hypotheses are diminished by the complete absence of any cicadas on a Brood I or Brood VI cycle in or near Carbon County(Cooley 2015); thus, each scenario requires that the shift away from the intermediate stage of either scenario be so complete that it left behind no local populations on the intermediate schedule.…”