RAPID COMMUNICATION FLORAL ODOR VARIATION IN TWO HETEROSTYLOUS SPECIES OF Primula

Abstract-Floral traits such as odor, color, and morphology are important pollinator attractants. Variation in floral traits may influence floral constancy, the tendency of pollinating insects to visit flowers of only one type. We investigated for the first time variation in odor between floral morphs in heterostylous species. We analyzed inter-and intraspecific odor variation in the Bpin^and Bthrum^floral morphs of sympatric Primula elatior and P. farinosa (Primulaceae). Floral volatiles were sampled with headspace sorption. Quantitative analysis and chemical identification were performed by gas chromatography coupled to mass spectrometry. The species produced different floral bouquets. P. elatior emitted mostly limonene with small amounts of a-pinene, myrcene, and sabinene. P. farinosa produced benzaldehyde, 4-oxoisophorone (2,6,6-trimethyl-2-cyclohexene-1,4-dione), benzyl alcohol, and benzyl acetate. These interspecific differences may play a role in promoting floral constancy and maintaining species integrity. Conversely, no differences were detected between the scents of pin and thrum morphs within each species. Heterostyly relies on pollinators visiting both floral morphs. There may be stabilizing selection against divergences in traits that may cause pollinators to develop floral constancy to only one of the floral morphs

Combining evolutionary inference and metabolomics to identify plants with medicinal potential

Plants have been a source of medicines in human cultures for millennia. The past decade has seen a decline in plant-derived medicines due to the time-consuming nature of screening for biological activity and a narrow focus on individual candidate plant taxa. A phylogenetically informed approach can be both more comprehensive in taxonomic scope and more systematic, because it allows identification of evolutionary lineages with higher incidence of medicinal activity. For these reasons, phylogenetics is being increasingly applied to the identification of novel botanic sources of medicinal compounds. These biologically active compounds are normally derived from plant secondary or specialized metabolites generally produced as induced responses and often playing a crucial role in plant defense against herbivores and pathogens. Since these compounds are typically bioactive they serendipitously offer potential therapeutic properties for humans, resulting in their use by traditional societies and ultimately drug lead development by natural product chemists and pharmacologists. The expression of these metabolites is likely the result of coevolutionary processes between plants and the other species with which they interact and effective metabolites are thus selected upon through evolution. Recent research on plant phylogeny coupled with metabolomics, which is the comprehensive analysis of metabolite profiles, has identified that related taxa produce similar secondary metabolites, although correlations are dependent also on environmental factors. Modern mass spectrometry and bioinformatic chemical networking tools can now assist high throughput screening to discover structurally related and potentially new bioactive compounds. The combination of these metabolomic approaches with phylogenetic comparative analysis of the expression of metabolites across plant taxa could therefore greatly increase our capacity to identify taxa for medicinal potential. This review examines the current status of identification of new plant sources of medicine and the current limitations of identifying plants as drug candidates. It investigates how ethnobotanic knowledge, phylogenetics and novel approaches in metabolomics can be partnered to help in characterizing taxa with medicinal potential

Artificial light at night correlates with seabird groundings: mapping city lights near a seabird breeding hotspot

Artificial light at night (ALAN) is a growing conservation concern for seabirds, which can become disoriented and grounded by lights from buildings, bridges and boats. Many fledgling seabirds, especially Procellariiformes such as petrels and shearwaters, are susceptible to light pollution. The Hauraki Gulf, a seabird hotspot located near Tāmaki Makaurau/Auckland, Aotearoa—New Zealand’s largest urban city, with a considerable amount of light pollution and regularly documented events of seabird groundings. We aim to identify the characteristics of locations especially prone to seabird groundings. We used an online database of seabirds taken to a wildlife rescue facility by the public to map 3 years of seabird groundings and test for correlations between seabird groundings and the natural night sky brightness. We found that areas with lower amounts of natural night sky brightness and greater light pollution often had a higher number of seabirds grounded. Further, we identified important seasonal patterns and species differences in groundings. Such differences may be a by-product of species ecology, visual ecology and breeding locations, all of which may influence attraction to lights. In general, seabird groundings correlate with the brightness of the area and are species-specific. Groundings may not be indicative of human or seabird population abundance considering some areas have a lower human population with high light levels and had high amounts of seabird groundings. These findings can be applied worldwide to mitigate groundings by searching and targeting specific brightly lit anthropogenic structures. Those targeted structures and areas can then be the focus of light mitigation efforts to reduce seabird groundings. Finally, this study illustrates how a combination of community science, and a concern for seabirds grounded from light attraction, in addition to detailed animal welfare data and natural night sky brightness data can be a powerful, collaborative tool to aid global conservation efforts for highly-at-risk animals such as seabirds

Quantifying variation in the ability of yeasts to attract Drosophila melanogaster

Yeasts that invade and colonise fruit significantly enhance the volatile chemical diversity of this ecosystem. These modified bouquets are thought to be more attractive to Drosophila flies than the fruit alone, but the variance of attraction in natural yeast populations is uncharacterised. Here we investigate how a range of yeast isolates affect the attraction of female D. melanogaster to fruit in a simple two choice assay comparing yeast to sterile fruit. Of the 43 yeast isolates examined, 33 were attractive and seven repellent to the flies. The results of isolate-versus-isolate comparisons provided the same relative rankings. Attractiveness varied significantly by yeast, with the strongly fermenting Saccharomyces species generally being more attractive than the mostly respiring non-Saccharomyces species (P = 0.0035). Overall the habitat (fruit or other) from which the isolates were directly sampled did not explain attraction (P = 0.2352). However, yeasts isolated from fruit associated niches were more attractive than those from non-fruit associated niches (P = 0.0188) regardless of taxonomic positioning. These data suggest that while attractiveness is primarily correlated with phylogenetic status, the ability to attract Drosophila is a labile trait among yeasts that is potentially associated with those inhabiting fruit ecosystems. Preliminary analysis of the volatiles emitted by four yeast isolates in grape juice show the presence/absence of ethanol and acetic acid were not likely explanations for the observed variation in attraction. These data demonstrate variation among yeasts for their ability to attract Drosophila in a pattern that is consistent with the hypothesis that certain yeasts are manipulating fruit odours to mediate interactions with their Drosophila dispersal agent. © 2013 Palanca et al

Orchid diversity : spatial and climatic patterns from herbarium records

Aim: We test for spatial and climatic patterns of diversification in the Orchidaceae, an angiosperm family characterized by high levels of species diversity and rarity. Globally, does orchid diversity correlate with land area? In Australia, does diversity correlate with herbarium collecting effort, range size, or climate niche breadth? Where are Australia’s orchids distributed spatially, in protected areas, and in climate space? Location: Global, then Australia. Methods: We compared orchid diversity with land area for continents and recognized orchid diversity hotspots. Then, we used cleaned herbarium records to compare collecting effort (for Australian Orchidaceae vs. all other plant families, and also among orchid genera). Spatial and climate distributions were mapped to determine orchids’ coverage in the protected area network, range sizes, and niche breadths. Results: Globally, orchid diversity does not correlate with land area (depauperate regions are the subantarctic: 10 species, and northern North America: 394 species). Australian herbarium records and collecting effort generally reflect orchid species diversity (1,583 spp.), range sizes, and niche breadths. Orchids are restricted to 13% of Australia’s landmass with 211 species absent from any protected areas. Species richness is the greatest in three biomes with high general biodiversity: Temperate (especially southwest and southeast Australia), Tropical, and Subtropical (coastal northern Queensland). Absence from the Desert is consistent with our realized climate niche—orchids avoid high temperature/low rainfall environments. Orchids have narrower range sizes than nonorchid species. Highly diverse orchid genera have narrower rainfall breadths than less diverse genera. Main conclusions: Herbarium data are adequate for testing hypotheses about Australian orchids. Distribution is likely driven by environmental factors. In contrast, diversification did not correlate with increases in range size, rainfall, or temperature breadths, suggesting speciation does not occur via invasion and local adaptation to new habitats. Instead, diversification may rely on access to extensive obligate symbioses with mycorrhizae and/or pollinators

Deception down under : is Australia a hot spot for deception?

The Australian continent is renowned for its idiosyncratic flora and fauna and high diversity of endemic taxa (e.g., Eucalyptus, marsupials, and monotremes; Braithwaite RW. 1990. Australia's unique biota: implications for ecological processes. J Biogeogr. 17:347-354.). Given this diversity, it is perhaps not surprising that Australia is a coveted and productive field site for behavioral ecologists worldwide. The prevalence of some unusual animal behaviors is well documented, such as cooperative breeding in birds, low rates of herbivory, and high rates of pollination by vertebrates. However, other behavioral phenomena, especially those involving deception and exploitation, are also remarkably prevalent in some systems and still require comprehensive treatment. We examine 3 distinct forms of deception in entirely different taxa, cuckoos, crab spiders, and orchids, where there is strong evidence that deception is more prevalent in Australia than in other geographic regions. We offer several explanations addressing environmental conditions, evolutionary isolation, the prevalence of behavioral ecologists, and the research culture in Australia. The aim of this "Idea" paper is to draw attention to intriguing patterns of deception in a limited number of well-studied systems and to generate several testable predictions. It is not intended as a thorough review of all deceptive systems, but we hope to stimulate more research, a systematic review, and further testing in this area.5 page(s

Data from: Floral community predicts pollinators' color preference: implications for Batesian floral mimicry

Animals that rely on nectar are expected to display floral trait preferences correlating to the signals of nectar source flowers. Batesian mimicry evolves to exploit these pre-existing signal-receiver relationships, attracting pollinators through an adaptive resemblance to specific co-occurring rewarding species. The nectar-feeding long-proboscid flies of South Africa are pollinators for several deceptive orchid species that are putatively Batesian mimics. We tested whether flies’ measured color preference varied among communities providing different nectar-source diets, which would indicate the necessary signal-receiver conditions for the evolution of advergent Batesian mimicry. We introduced artificial rewardless flowers into flowering communities that supported divergent nectar-diets in resident flies and inferred floral trait preferences of a long-proboscid fly species (Prosoeca ganglbaueri) from visitation behavior to these artificial flowers. The experiment showed that the preference of flies for white versus pink was strongly predicted by the colors of flowers most commonly visited by flies at a site. Furthermore, generalization in preference was positively correlated with the variance in nectar-community hue, i.e. flies showed more generalized preference in more spectrally diverse flower communities. The floral tube length of local nectar sources also influenced how readily the flies probed the artificial flowers during attempted foraging. These results support the hypothesis that nectarless orchids pollinated by P. ganglbaueri experience selection for traits that exploit site-specific mutualistic relationships between fly pollinators and their local floral communities

Resilience of haplodiploids to being exploited by sexually deceptive plants

In species with obligate sexual reproduction, scarcity of males can occasionally limit female reproductive success. It is unclear, however, whether this impacts population-level persistence. Sexually deceptive orchids attract mate-searching male insects who lose time, mating opportunities and may even become sperm depleted by mating with flowers. These insects are almost exclusively haplodiploid, and able to reproduce regardless of sperm availability – which might mitigate costs of deception. We model the population dynamics of deceived diploid or haplodiploid pollinators. The model reveals that haplodiploidy can enhance prospects for coexistence. If ‘sperm theft' by orchids is severe enough to generate unmated females in the local pollinator pool, this enhances the production of sons, which are subsequently available to act as pollinators. The mechanism relies on female haplodiploids being able to reproduce with or without sperm; this is absent in many diploid insects – where unmated females do not reproduce. We show that this gives haplodiploids an ability to maintain higher population densities, and to persist up to higher orchid densities, than diploids. Our model identifies the enhanced resilience of haplodiploid pollinators against deceptive exploitation as a possible reason why these systems have persisted

Spectral and behavioral data

Average spectra for flowers in the study. Behavioral response data to interview bouquets

Data from: Exotic flies maintain pollination services as native pollinators decline with agricultural expansion

1.Globally, conversion of natural habitat to agricultural land is a primary driver of declines in critical ecosystem services, including pollination. However, exotic species are often well-adapted to human-modified environments and could compensate for ecosystem services that are lost when native species decline. 2.We measured pollination services (pollen delivery to stigma) provided by wild insects to a mass flowering crop, pak choi Brassica rapa at 12 sites across a gradient of increasing agricultural land use (agricultural expansion) in New Zealand. 3.We found that pollination services increased as the proportion of agricultural land in the surrounding landscape increased; pollination from exotic species exceeded the loss of pollination from native species. However, pollination service delivery became increasingly dominated by a few exotic fly species that were active throughout the day, compared to native species, which had more constrained activity patterns. 4.Synthesis and applications. The best way to ensure continued sufficient crop pollination is to protect and restore diverse natural habitats on or around farms, as species-rich pollinator communities are relatively resilient to further environmental change. However, we show that where human-driven disturbance has caused loss of native pollinator species, exotic pollinators can maintain sufficient pollination. Therefore, in areas where native species loss cannot easily be reversed, decisions about pesticide use and habitat provision that foster populations of beneficial exotic species are likely to maintain pollination service delivery, at least in the short term. This highlights the need for land managers to identify the pollinator communities that are present on their farms, whether native or exotic, and make decisions to support these important communities accordingly