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We conducted a literature review and added some novel observations of the natural history of the bordered patch butterfly, Chlosyne lacinia (Nymphalidae). Regarding color and patterning, C. lacinia is considered one of the most variable butterflies in the Western Hemisphere, with phenotypic variation occurring in larvae, pupae, and adults. Several studies have been conducted on C. lacinia, partly due to its notable phenotypic variation and status as a pest species of domestic sunflowers (Helianthus annuus). Even so, the origins, development, and maintenance of phenotypic variation remain poorly known. Having the most extensive geographic range of any species in its genus, C. lacinia ranges from Argentina to the mid-latitude midwestern United States. Moreover, C. lacinia displays six distinct adult morphs across its geographic range. Morphologically continuous, relatively geographically narrow gradients between adjacent morphs have given rise to alternative interpretations about subspecies. By providing the first comprehensive maps of adult morphs, including data collected via citizen science in iNaturalist, we provide directions for further research into the species' biology. Realizamos una revisión bibliográfica sobre la historia natural de la mariposa del parche bordeado, Chlosyne lacinia (Nymphalidae) que complementamos con observaciones nuevas. En cuanto al color y el patrón, C. lacinia se considera una de las mariposas más variables del hemisferio occidental, con variación fenotípica en larvas, pupas y adultos. Se han realizado numerosos estudios sobre C. lacinia, principalmente debido a su notable variación fenotípica y a su condición de especie plaga del girasol doméstico (Helianthus annuus). Aun así, el origen, desarrollo y mantenimiento de esta variación fenotípica siguen siendo poco estudiados. Teniendo la distribución geográfica más extensa de todas las especies de su género, C. lacinia se encuentra desde Argentina hasta latitudes medias del medio oeste de Estados Unidos. Además, C. lacinia presenta seis distintos morfos adultos a través de su distribución geográfica. Debido a que morfos geográficamente adyacentes presentan una morfología continua entre ellos, el reconocimiento de las subespecies es controversial. A través de mapas de distribución de cada morfo adulto con datos de iNaturalist, planteamos hipótesis y preguntas para futuras investigaciones sobre la biología de esta especie. 

As an abundant element in the Earth’s crust, sodium plays an unusual role in food webs. Its availability in terrestrial environments is highly variable, but it is nonessential for most plants, yet essential for animals and most decomposers. Accordingly, sodium requirements are important drivers of various animal behavioural patterns and performance levels. To specifically test whether sodium limitation increases cannibalism in a gregarious lepidopteran herbivore, we hydroponically manipulatedHelianthus annuushost plants' tissue-sodium concentrations. Gregarious larvae of the bordered patch butterfly,Chlosyne lacinia, cannibalized siblings when plant-tissue sodium concentrations were low in two separate experiments. Although cannibalism was almost non-existent when sodium concentrations were high, individual mortality rates were also high. Sodium concentration in host plants can have pronounced effects on herbivore behaviour, individual-level performance, and population demographics, all of which are important for understanding the ecology and evolution of plant-animal interactions across a heterogeneous phytochemical landscape.

 

Some mistletoe species (Loranthaceae) resemble their host plants to a striking degree. Various mechanisms have been proposed for the developmental origins of novel traits that cause mistletoes to appear similar to their hosts, as well as for the adaptive phenotypic evolution of such traits. Calder (1983) proposed a logically flawed group selectionist seed‐dispersal hypothesis for mistletoes to resemble their hosts. Calder's (1983) hypothesis does not provide a viable potential explanation for mistletoe resemblance to hosts. 

As an essential micronutrient for many organisms, sodium plays an important role in ecological and evolutionary dynamics. Although plants mediate trophic fluxes of sodium, from substrates to higher trophic levels, relatively little comparative research has been published about plant growth and sodium accumulation in response to variation in substrate sodium. Accordingly, we carried out a systematic review of plants' responses to variation in substrate sodium concentrations.

We compared biomass and tissue‐sodium accumulation among 107 cultivars or populations (67 species in 20 plant families), broadly expanding beyond the agricultural and model taxa for which several generalizations previously had been made. We hypothesized a priori response models for each population's growth and sodium accumulation as a function of increasing substrate NaCl and used Bayesian Information Criterion to choose the best model. Additionally, using a phylogenetic signal analysis, we tested for phylogenetic patterning of responses across taxa.

The influence of substrate sodium on growth differed across taxa, with most populations experiencing detrimental effects at high concentrations. Irrespective of growth responses, tissue sodium concentrations for most taxa increased as sodium concentration in the substrate increased. We found no strong associations between the type of growth response and the type of sodium accumulation response across taxa. Although experiments often fail to test plants across a sufficiently broad range of substrate salinities, non‐crop species tended toward higher sodium tolerance than domesticated species. Moreover, some phylogenetic conservatism was apparent, in that evolutionary history helped predict the distribution of total‐plant growth responses across the phylogeny, but not sodium accumulation responses.

Our study reveals that saltier plants in saltier soils proves to be a broadly general pattern for sodium across plant taxa. Regardless of growth responses, sodium accumulation mostly followed an increasing trend as substrate sodium levels increased.

 

When Darwin visited the Galapagos archipelago, he observed that, in spite of the islands’ physical similarity, members of species that had dispersed to them recently were beginning to diverge from each other. He postulated that these divergences must have resulted primarily from interactions with sets of other species that had also diverged across these otherwise similar islands. By extrapolation, if Darwin is correct, such complex interactions must be driving species divergences across all ecosystems. However, many current general ecological theories that predict observed distributions of species in ecosystems do not take the details of between-species interactions into account. Here we quantify, in sixteen forest diversity plots (FDPs) worldwide, highly significant negative density-dependent (NDD) components of both conspecific and heterospecific between-tree interactions that affect the trees’ distributions, growth, recruitment, and mortality. These interactions decline smoothly in significance with increasing physical distance between trees. They also tend to decline in significance with increasing phylogenetic distance between the trees, but each FDP exhibits its own unique pattern of exceptions to this overall decline. Unique patterns of between-species interactions in ecosystems, of the general type that Darwin postulated, are likely to have contributed to the exceptions. We test the power of our null-model method by using a deliberately modified data set, and show that the method easily identifies the modifications. We examine how some of the exceptions, at the Wind River (USA) FDP, reveal new details of a known allelopathic effect of one of the Wind River gymnosperm species. Finally, we explore how similar analyses can be used to investigate details of many types of interactions in these complex ecosystems, and can provide clues to the evolution of these interactions.