Lawrence F. Gall

Climate change impacts on bumblebees converge across continents

Bucking the trend Responses to climate change have been observed across many species. There is a general trend for species to shift their ranges poleward or up in elevation. Not all species, however, can make such shifts, and these species might experience more rapid declines. Kerr et al. looked at data on bumblebees across North America and Europe over the past 110 years. Bumblebees have not shifted northward and are experiencing shrinking distributions in the southern ends of their range. Such failures to shift may be because of their origins in a cooler climate, and suggest an elevated susceptibility to rapid climate change. Science, this issue p. 177 Cool-adapted bumblebees are failing to shift their ranges in response to climate warming. For many species, geographical ranges are expanding toward the poles in response to climate change, while remaining stable along range edges nearest the equator. Using long-term observations across Europe and North America over 110 years, we tested for climate change–related range shifts in bumblebee species across the full extents of their latitudinal and thermal limits and movements along elevation gradients. We found cross-continentally consistent trends in failures to track warming through time at species’ northern range limits, range losses from southern range limits, and shifts to higher elevations among southern species. These effects are independent of changing land uses or pesticide applications and underscore the need to test for climate impacts at both leading and trailing latitudinal and thermal limits for species.

A Single Origin for Nymphalid Butterfly Eyespots Followed by Widespread Loss of Associated Gene Expression

Understanding how novel complex traits originate involves investigating the time of origin of the trait, as well as the origin of its underlying gene regulatory network in a broad comparative phylogenetic framework. The eyespot of nymphalid butterflies has served as an example of a novel complex trait, as multiple genes are expressed during eyespot development. Yet the origins of eyespots remain unknown. Using a dataset of more than 400 images of butterflies with a known phylogeny and gene expression data for five eyespot-associated genes from over twenty species, we tested origin hypotheses for both eyespots and eyespot-associated genes. We show that eyespots evolved once within the family Nymphalidae, approximately 90 million years ago, concurrent with expression of at least three genes associated with early eyespot development. We also show multiple losses of expression of most genes from this early three-gene cluster, without corresponding losses of eyespots. We propose that complex traits, such as eyespots, may have originated via co-option of a large pre-existing complex gene regulatory network that was subsequently streamlined of genes not required to fulfill its novel developmental function.

Assessing declines of North American bumble bees (Bombus spp.) using museum specimens

Bumble bees are an important group of wild pollinators in North America and considerable concern has been expressed over declines in their populations. However, before causes for declines can be assessed, it is essential that the geographical and chronological patterns of decline be discovered. Hitherto a lack of assessment of historical data has hindered our efforts to determine which species are most at risk. Here, the status of 21 North American bumble bee species (Hymenoptera: Apidae) occurring in the eastern nearctic biogeographic region is assessed using a specimen-level database from compiled museum and survey records dating back to the late nineteenth century from various institutional collections. Using a combination of measures, bumble bee declines were assessed over their entire native ranges. We report here that half of the selected fauna is in varying levels of decline (especially Bombus ashtoni, B. fervidus, and B. variabilis), with the remaining species exhibiting stable or increasing trends (e.g., B. bimaculatus, B. impatiens, and B. rufocinctus). Suggestions for prioritizing conservation efforts for this important group of pollinators are given.

The effects of capturing and marking on subsequent activity in Boloria acrocnema (Lepidoptera: Nymphalidae), with a comparison of different numerical models that estimate population size

Abstract Capturing and marking disrupts flight activity in the alpine fritillary butterfly, Boloria acrocnema. This effect is limited to the date an individual receives its mark, and does not appear to increase mortality significantly. It nevertheless can generate large positive biases in population size estimates, especially in single-census mark-recapture models. The bias may overestimate by 2 to 4 times the actual population size. Similar marking effects in several other Lepidoptera are also analysed. Tests for the presence of marking effects are reviewed, with discussion of the general influence they have on population data.

Population structure and recommendations for conservation of the narrowly endemic alpine butterfly, Boloria acrocnema (Lepidoptera: Nymphalidae)

Abstract Boloria acrocnema is a glacial relict species, known from two colonies in alpine southwestern Colorado, USA. Mark-recapture techniques were used to analyse its population structure at its type locality, Mt Uncompahgre. Adult activity there is confined largely to about 1 ha in which the larval foodplant, Salix nivalis, is abundant. Mark-recapture data indicate that daily population sizes are low, most adults remain in residence at the colony only a few days, and there are age-specific sexual differences in movement, with older females perhaps leaving the colony site. Survival of B. acrocnema is probably governed by a pattern of local extinctions, counter-balanced by colonizations of new habitat. The autoecology of B. acrocnema is discussed in the light of present conservation needs of this butterfly. Management actions being taken by several agencies are also presented; these include enforcing grazing restrictions, monitoring collecting pressure, and formal listing of this species under federal and state endangered species programmes.

Nymphalid eyespot serial homologues originate as a few individualized modules

Serial homologues are repeated traits that share similar development but occur in different parts of the body. Variation in number of repeats accounts for substantial diversity in animal form and considerable work has focused on identifying the factors accounting for this variation. Little is known, however, about how serial homologues originally become repeated, or about the relative timing of repeat individuation relative to repeat origin. Here, we show that the serially repeated eyespots on nymphalid butterfly wings most likely arose as a small cluster of units on the ventral hindwing that were later co-opted to the dorsal and anterior wing surfaces. Based on comparative analyses of over 400 species, we found support for a model of eyespot origin followed by redeployment, rather than by the conventional model, where eyespots arose as a complete row of undifferentiated units that later gained individuation. In addition, eyespots most likely evolved from simpler pattern elements, single-coloured spots, which were already individuated among different wing sectors. Finally, the late appearance of eyespots on the dorsal, hidden wing surface further suggests that these novel complex traits originally evolved for one function (thwarting predator attacks) and acquired a second function (sexual signalling) when moved to a different body location. This broad comparative analysis illustrates how serial homologues may initially evolve as a few units serving a particular function and subsequently become repeated in novel body locations with new functions.

A Fossil Noctuid Moth Egg from the Late Cretaceous of Eastern North America

A moth egg assignable to the family Noctuidae (Lepidoptera) is described from 75-million-year-old sediments from Marthas Vineyard, Massachusetts. This sample, which extends the fossil record of this farnily and modern heteroneuran moths back to the Cretaceous, may provide insight into the coevolution of moths and flowering plants, as well as have implications for the evolution of bats.

LepNet: The Lepidoptera of North America Network

The Lepidoptera of North America Network, or LepNet, is a digitization effort recently launched to mobilize biodiversity data from 3 million specimens of butterflies and moths in United States natural history collections (http://www.lep-net.org/). LepNet was initially conceived as a North American effort but the project seeks collaborations with museums and other organizations worldwide. The overall goal is to transform Lepidoptera specimen data into readily available digital formats to foster global research in taxonomy, ecology and evolutionary biology.

Relocation risky for bumblebee colonies—Response.

Lozier et al. accept our findings but take issue with a concluding sentence alluding to relocation to mitigate potential climate change impacts on bumblebee species. We welcome thoughtful discussion of this admittedly difficult area ([ 1 ][1]). However, Lozier et al. present an idiosyncratic view of

Systematics of Moths in the Genus Catocala (Lepidoptera: Noctuidae). V. Neotypification of Names in the Nearctic Fauna

Abstract Nine previously published neotype designations in the noctuid moth genus Catocala are reviewed for compliance with the International Code of Zoological Nomenclature. Eight of the designations are found to have not fulfilled one (75.3.2) of the seven qualifying conditions of Article 75.3 when these were originally published, and are redesignated herein. The eight Catocala names involved are connubialis Guenée, dollii Beutenmüller, grotiana Bailey, irene Behr, micronympha Guenée, stretchii Behr, texanae French and walshii Edwards. The ninth neotype designation, for calphurnia Henry Edwards, is considered valid as originally published.