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In this letter, we focus on a very curious and bibliometrically important case of a 2017 moth pheromone paper published in Cell Press' Current Biology that has already accumulated over 1600 Google Scholar-based citations within the past 4 years (i.e., since 2020) to appreciate whether all those citations are valid, i.e., within thematic scope, or whether a portion of those citations might be invalid, and which we colloquially refer to herein as "unwanted citations". Our investigation assessed Scopus-based data (1088 citations on 10 August 2023). In addition to creating a SciVal thematic profile, which indicated a wide diversity of topics of papers citing the 2017 paper, a manual screen revealed only one paper that was directly thematically relevant to the topic of insect reproductive biology. The remaining > 99% of citations, or "unwanted citations", are invalid. To reflect a valid state of scientific truthfulness, those papers should be corrected to reflect that citation abuse has taken place. [ABSTRACT FROM AUTHOR]

Reproductive isolation between sympatric, closely related species can be accomplished through a variety of pre-zygotic isolating mechanisms, including courtship-signaling behavior that involves pheromones. In the moths Heliothis virescens and H. subflexa, males display abdominal hairpencils (HP), which release volatile chemicals during courtship. In this study, we demonstrated that HP volatiles released by male H. subflexa function to improve mating success with conspecific females. Interspecific mating experiments were conducted to determine any influence of HP volatiles on species isolation. Female H. virescens and H. subflexa were observed during courtship with males of the other species, following either sham-operation or ablation of HPs, both with and without concurrent presentation of HP volatiles. Mating success was improved by co-presentation of HP extract from males of the same species during courtship. Ablation of HPs improved mating between H. subflexa females and H. virescens males. During interspecific matings, male H. virescens attempted copulation less frequently in the presence of H. virescens HP extract, though H. subflexa males were not affected by the presence of H. subflexa HP extract. This suggests that HP volatiles produced by males of each species may inhibit mating between species through effects on males ( H. virescens) and females ( H. subflexa). [ABSTRACT FROM AUTHOR]

Heliothis subflexa males were flown in a wind tunnel to a variety of combinations of synthetic pheromone components admixed on a filter paper disk. Blends containing ( Z)-11-hexadecenal ( Z11–16:Ald, 1000 ng), ( Z)-9-hexadecenal ( Z9–16:Ald, 500 ng) and ( Z)-11-hexadecenol ( Z11–16:OH, 10–500 ng) elicited upwind flight and source contact in 52–69% of males. All these compounds have previously been isolated and identified from female H. subflexa gland extracts and volatile pheromone emissions. Males were not attracted by blends in which Z9–16:Ald was omitted (0% source contact). Similarly, blends lacking Z11–16:OH were unattractive to male H. subflexa (3% or less source contact). Males were extremely sensitive to the presence of Z11–16:OH; however, responding in high numbers (57–69% source contact) to blends containing a dosage of 1% (10 ng) or greater Z11–16:OH. Males were unresponsive to blends in which Z9–16:Ald was replaced with a variety of dosages of ( Z)-9-tetradecenal, a secondary component of a closely-related congeneric species, Heliothis virescens. Another compound present in the blend emitted by conspecific females, ( Z)-11-hexadecenyl acetate ( Z11–16:Ac), did not inhibit H. subflexa males (69% source contact) when added to the three-component mixture (1:0.5:0.1) at a ratio of 0.1 (100 ng) with respect to Z11–16:Ald. These results indicate that Z9–16:Ald and Z11–16:OH are required in addition to Z11–16:Ald to elicit significant levels of upwind flight in H. subflexa males. The effects of Z11–16:Ac are more subtle, but at the dosage tested in these experiments, this compound does not have an antagonistic effect on upwind flight and source location by H. subflexa males. [ABSTRACT FROM AUTHOR]

Shows that with naturally intermittent odor stimulation, spike patterns recorded from moth antennal-lobe output neurons varied predictably with the fine-scale temporal dynamics and intensity of the odor. How this finding supports the hypothesis the olfactory circuits compensate for contextual variations in the stimulus pattern with high temporal precision; Observation that the timing of output neuron activity is constantly modulated to reflect ongoing changes in stimulus intensity and dynamics that occur on a millisecond timescale.

Addition of ( Z)-11-hexadecenyl acetate (Z11-16:Ac) into a normally attractive binary blend of Heliothis virescens pheromone components resulted in a suppression of upwind flight and source location by males. Male response was reduced even at the lowest dosages of Z11-16:Ac tested but upwind flight and source location were most clearly reduced when the loading of Z11-16:Ac reached 10% or more of the ( Z)-11-hexadecenal (Z11-16:Ald) loading (the major component present in the binary blend). Similar patterns of suppression in response were noted when Z11-16:Ac was added to binary blends of pheromone components at both 10 and 100 μg loadings of Z11-16:Ald. Males in casting flight following upwind flight in a mechanically generated pulsed plume, responded to the interception of a subsequent, single binary-blend filament by making a toward-source upwind surge. Responses of males to a single filament that was tainted by a level of Z11-16:Ac that had allowed some reduced level of upwind flight and source location to occur in the previous plume experiments were diminished compared with their control counterparts. Analysis of the flight tracks revealed that the surges in response to single tainted filaments were stunted because males made fewer significant changes in course angles steered, airspeeds generated, and in the tempo of counterturns executed. [ABSTRACT FROM AUTHOR]