Supporting Spartina: Interdisciplinary perspective shows Spartina as a distinct solid genus

In 2014, a DNA-based phylogenetic study confirming the paraphyly of the grass subtribe Sporobolinae proposed the creation of a large monophyletic genus Sporobolus, including (among others) species previously included in the genera Spartina, Calamovilfa, and Sporobolus. Spartina species have contributed substantially (and continue contributing) to our knowledge in multiple disciplines, including ecology, evolutionary biology, molecular biology, biogeography, experimental ecology, biological invasions, environmental management, restoration ecology, history, economics, and sociology. There is no rationale so compelling to subsume the name Spartina as a subgenus that could rival the striking, global iconic history and use of the name Spartina for over 200 yr. We do not agree with the subjective arguments underlying the proposal to change Spartina to Sporobolus. We understand the importance of both the objective phylogenetic insights and of the subjective formalized nomenclature and hope that by opening this debate we will encourage positive feedback that will strengthen taxonomic decisions with an interdisciplinary perspective. We consider that the strongly distinct, monophyletic clade Spartina should simply and efficiently be treated as the genus Spartina

Data from: Latitudinal patterns of herbivore pressure in a temperate herb support the biotic interactions hypothesis

The longstanding biotic interactions hypothesis predicts that herbivore pressure declines with latitude, but the evidence is mixed. To address gaps in previous studies, we measured herbivory and defense in the same system, quantified defense with bioassays, and considered effects of leaf age. We quantified herbivory and defense of young and mature leaves along a continental gradient in eastern North America in the native herb Phytolacca americana. Herbivory in the field declined with latitude and was strongly correlated with Lepidopteran abundance. Laboratory bioassays revealed that leaf palatability was positively correlated with latitude of origin. Young leaves were more damaged than mature leaves at lower latitudes in the field, but less palatable in bioassays. Both defense and palatability displayed non-linear latitudinal patterns, suggesting potential mechanisms based on biological or climatic thresholds. In sum, observational and experimental studies find patterns consistent with high herbivore pressure and stronger plant defenses at lower latitudes