Since the 1980s, the existence of one or more extinction events in the late Ediacaran has been the subject of debate. Discussion surrounding these events has intensified in the last decade, in concert with efforts to understand drivers of global change over the Ediacaran–Cambrian transition and the appearance of the more modern-looking Phanerozoic biosphere. In this paper we review the history of thought and work surrounding late Ediacaran extinctions, with a particular focus on the last 5 years of paleontological, geochemical, and geochronological research. We consider the extent to which key questions have been answered, and pose new questions which will help to characterize drivers of environmental and biotic change. A key challenge for future work will be the calculation of extinction intensities that account for limited sampling, the duration of Ediacaran ‘assemblage’ zones, and the preponderance of taxa restricted to a single ‘assemblage’; without these data, the extent to which Ediacaran bioevents represent genuine mass extinctions comparable to the ‘Big 5’ extinctions of the Phanerozoic remains to be rigorously tested. Lastly, we propose a revised model for drivers of late Ediacaran extinction pulses that builds off recent data and growing consensus within the field. This model is speculative, but does frame testable hypotheses that can be targeted in the next decade of work.

Extinction is a new open-access journal focused on the patterns and processes underlying the loss of biodiversity. It aims to inform conservation efforts, with a broad spatial and temporal scope. Extinction biology – the scientific study of species loss – has a long history and has recently become a more interdisciplinary and integrated field. This journal offers a unique, synthetic forum in which to present cutting-edge research and discuss its implications. This includes ecological, molecular, paleontological, and social perspectives, based on empirical data, theory, and modelling, to understand extinction processes. By tackling the big challenges, the research published in Extinction will be valuable for researchers and practitioners concerned with extinction and its role in shaping the history and future of life on Earth.

Termites are essential components of tropical ecosystems, in which they provide fundamental ecosystem services, such as decomposition of dead plant material, fostering of soil mineralization and provisioning of new microhabitats. We investigated the termite communities of four habitats in two protected areas in West Africa, which differ in management effectiveness: the strictly protected Lamto Reserve (LR) and the Marahoué National Park (MNP), which suffers from anthropogenic disturbance despite its protection status. We tested the effect of disturbance on species composition, richness and abundance as well as on functional (feeding type) composition. The effect of disturbance was clearly visible in the termite communities. Compared to the LR, the MNP had less termite species overall and in all habitats except the shrub savannah. Also the abundance of termites was generally reduced and a decrease of soil feeders recorded. The latter is well-known to be sensitive to anthropogenic disturbance in forests. Comparing our results with other studies, we were able to identify suitable bioindicators of ecosystem health for West-African savannahs. Furthermore, we discuss the potential consequences of anthropogenic disturbance on ecosystem services provided by termites.

Understanding how raptors select prey is important to determine taphonomic biases both in modern and paleo pellet assemblages. We tested whether pellets more closely represent raptor dietary specialization or local small mammal diversity by sampling pellets from seven raptor species across four study sites in Yellowstone National Park, Wyoming, USA. We identified small mammal craniodental elements from each pellet and tested for differences among small mammal assemblages for each raptor species and study site. We found that reconstructed avian predator diets clustered significantly by site but not by predator species. Bray-Curtis diet dissimilarities were also significantly lower when comparing different raptor species within a site than when comparing the same raptor species across different sites. Our results suggest that raptors choose to eat a diversity of small mammal species close to their roosts rather than fly long distances to specialize on a particular prey species. Neontologists and paleoecologists alike can therefore be confident that raptor pellets faithfully represent local small mammal diversity.

In different parts of the world, aphid populations and their natural enemies are influenced by landscapes and climate. In the Neotropical region, few long-term studies have been conducted, maintaining a gap for comprehension of the effect of meteorological variables on aphid population patterns and their parasitoids in field conditions. This study describes the general patterns of oscillation in cereal winged aphids and their parasitoids, selecting meteorological variables and evaluating their effects on these insects. Aphids exhibit two annual peaks, one in summer–fall transition and the other in winter-spring transition. For parasitoids, the highest annual peak takes place during winter and a second peak occurs in winter–spring transition. Temperature was the principal meteorological regulator of population fluctuation in winged aphids and parasitoids during the year. The favorable temperature range is not the same for aphids and parasitoids. For aphids, temperature increase resulted in population growth, with maximum positive effect at 25°C. Temperature also positively influenced parasitoid populations, but the growth was asymptotic around 20°C. Although rainfall showed no regulatory function on aphid seasonality, it influenced the final number of insects over the year. The response of aphids and parasitoids to temperature has implications for trophic compatibility and regulation of their populations. Such functions should be taken into account in predictive models.

A paleontological deposit near San Clemente de Térapa represents one of the very few Rancholabrean North American Land Mammal Age sites within Sonora, Mexico. During that time, grasslands were common, and the climate included cooler and drier summers and wetter winters than currently experienced in northern Mexico. Here, we demonstrate restructuring in the mammalian community associated with environmental change over the past 40,000 years at Térapa. The fossil community has a similar number of carnivores and herbivores whereas the modern community consists mostly of carnivores. There was also a 97% decrease in mean body size (from 289 kg to 9 kg) because of the loss of megafauna. We further provide an updated review of ungulates and carnivores, recognizing two distinct morphotypes of Equus, including E. scotti and a slighter species; as well as Platygonus compressus; Camelops hesternus; Canis dirus; and Lynx rufus; and the first regional records of Palaeolama mirifica, Procyon lotor, and Smilodon cf. S. fatalis. The Térapa mammals presented here provide a more comprehensive understanding of the faunal community restructuring that occurred in northern Mexico from the late Pleistocene to present day, indicating further potential biodiversity loss with continued warming and drying of the region.

Among the Brazilian marsupials, the species of the genus Didelphis are the most parasitized by helminths. This study aimed to describe the species composition and to analyse the helminth communities of the Atlantic Forest common opossum Didelphis aurita at infracommunity and component community levels using the Elements of Metacommunity Structure Analysis, considering peri-urban, sylvatic and rural environments in the state of Rio de Janeiro, Brazil. Seventy-three specimens of D. aurita were captured during the study. Fourteen species of helminths were collected: nine of the phylum Nematoda (Trichuris minuta, Trichuris didelphis, Globocephalus marsupialis, Heterostrongylus heterostrongylus, Travassostrongylus orloffi, Viannaia hamata, Aspidodera raillieti, Cruzia tentaculata and Turgida turgida); four of the phylum Platyhelminthes (three species of Trematoda, Duboisiella proloba, Brachylaima advena and Rhopalias coronatus, and one species of the class Cestoda); and one species of the phylum Acanthocephala (Oligacanthorhynchus microcephalus). More than 95% of the animals were infected with parasites. The most abundant parasite species were V. hamata, T. turgida, C. tentaculata and T. orloffi. The nematodes T. turgida, C. tentaculata and A. raillieti were the most dominant species in the three environments. The analysis of the metacommunity structure indicated a structured pattern as a function of the environmental gradient, but only when all localities were considered together. At the infracommunity and component community levels, quasi-nested and nested structures with stochastic species loss were observed, respectively. The results indicate that the settlement of helminth species in the opossums can be attributed to the heterogeneity among individual hosts in relation to their exposure to parasites and to extrinsic factors, which vary among habitats, considering a regional scale. On a local scale, the characteristics of this host species may promote homogenization among individual hosts in terms of their exposure to the helminths. This study constitutes a new host record for the species G. marsupialis and T. didelphis and represents a pioneering investigation of the helminth metacommunity of a Neotropical marsupial.

To address how seasonality affects the richness and abundance of tropical insects, we compared the canopy and understorey communities of fruit-feeding butterflies in a seasonal Atlantic forest in south-eastern Brazil. Butterflies were sampled over 1 y using a standardized design with baited traps. A total of 2047 individuals in 69 species were recorded (1415 in the canopy, 632 in the understorey). Clear differences were found between canopy and understorey, with significantly higher butterfly abundances in the canopy. We observed two marked peaks of abundance and richness in both strata; one at the transition from dry to the wet seasons, and the other at the transition from wet to dry seasons. We found lower species turnover throughout the year in the canopy. We interpret this as evidence that temperature is more important than rainfall in explaining the yearly variation of abundance in vertical strata. The higher temperatures found in the canopy may allow butterflies to maintain activity in this stratum all year round, whereas the understorey is subject to colder temperatures, thus presenting a higher species turnover. These results improve our understanding of diversity gradients between evergreen and seasonal tropical forests, allowing insights into how climate and beta diversity gradients interact.

Despite metabarcoding being widely used to analyse bacterial community composition, its application in parasitological research remains limited. What interest there has been has focused on previously intractable research settings where traditional methods are inappropriate, for example, in longitudinal studies and studies involving endangered species. In settings such as these, non-invasive sampling combined with metabarcoding can provide a fast and accurate assessment of component communities. In this paper we review the use of metabarcoding in the study of helminth communities in wild mammals, outlining the necessary procedures from sample collection to statistical analysis. We highlight the limitations of the metabarcoding approach and speculate on what type of parasitological study would benefit from such methods in the future.

Riparian forests (RF) provide shelter, feeding resources and commuting areas and are fundamental for local fauna during long drought periods in tropical dry forests. Nevertheless, information regarding vertebrate ecology in tropical RF is scarce. The studies of bats in riparian habitats have been mostly focused on insectivorous assemblages in non-tropical regions. We contrasted the occurrence of frugivorous bats between RF and upland dry forest (UDF) in a Neotropical dry forest region and evaluated how vegetation structure modulates frugivorous bat presence and abundance. We sampled bat ensembles and vegetation structure in three UDF and three RF sites in Jalisco, Mexico. Bat ensembles and populations were analysed with generalized linear models, including as independent factors: (1) habitat and (2) vegetation attributes. In 72 nights we captured 840 bats belonging to seven species. No effect of habitat type or vegetation structure on species richness was found, but habitat type did affect bat species composition and abundance. Moreover, vegetation structural traits affected frugivorous bat abundance. Frugivore abundance was higher in RF than in UDF probably because RF provides greater resources and more roosting sites. Riparian forests also present more canopy cover and accessible flight spaces. Our results support the importance of RF for frugivorous bats in terms of abundance and composition. Additionally, the lack of differences in species richness between UDF and RF highlights the importance of both habitats for maintaining frugivorous bats, as well as the related ecosystem processes and services in tropical dry forest landscapes.

When animals or groups of animals in their wild habitats come close to each other within a defined distance, it is termed as an association. Observing two groups of the lion-tailed macaque at Nelliyampathy and Andiparai forests of the Western Ghats of India, we asked whether the lion-tailed macaque associations with the sympatric Nilgiri langur and bonnet macaque were by chance or had any biological significance. Employing ‘all occurrences’ sampling, we recorded an association if a group of another primate species came within 30 m of the focal group of the lion-tailed macaque. Date, time, associating species, activity of the study species and of the associating species, type of interaction, aggressor and the recipient, species displaced and duration of the association were recorded. We used the Waser gas model to calculate the expected frequency and duration of associations and compared them with the observed associations. The lion-tailed macaque spent less time in associations than expected. The lion-tailed macaque and the Nilgiri langur initiated associations less often, and remained in association for less time, than expected by chance. Whereas the expected and observed initiation of associations between the lion-tailed macaque and the Nilgiri langur in Nelliyampathy was significantly different (expected rate = 153; observed rate = 64), in Andiparai, it was not (expected rate = 55.5; observed rate = 61). The expected and observed association duration was significantly different in Nelliyampathy (expected duration = 54 min; observed duration = 15 min) and Andiparai (expected duration = 48 min; observed duration = 19 min). In contrast, we detected few differences between observed and expected association frequency for the lion-tailed macaque and the bonnet macaque. Aggressive interactions were common in areas where density of the Nilgiri langur groups was high. This is the first study on Asian primates using the ideal gas approach to show that primates do not form active associations with each other.

Reproductive interference is one of the major factors mediating species exclusion among insects. The cryptic species Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) of the whitefly Bemisia tabaci complex have invaded many parts of the world and often exhibit niche overlap and reproductive interference. However, contrasting patterns of competitive displacement between the two invaders have been observed between regions such as those in USA and China. Understanding the roles of reproductive interference in competitive interactions between populations of the two species in different regions will help unravel other factors related to their invasion. We integrated laboratory population experiments, behavioural observations and simulation modelling to investigate the role of reproductive interference on species exclusion between MEAM1 and MED in China. In mixed cohorts of the two species MEAM1 always excluded MED in a few generations when the initial proportion of MEAM1 was ⩾0.25. Even when the initial proportion of MEAM1 was only 0.10, however, MEAM1 still had a higher probability of excluding MED than that for MED to exclude MEAM1. Importantly, we show that as MEAM1 increased in relative abundance, MED populations became increasingly male-biased. Detailed behavioural observations confirmed that MEAM1 showed a stronger reproductive interference than MED, leading to reduced frequency of copulation and female progeny production in MED. Using simulation modelling, we linked our behavioural observations with exclusion experiments to show that interspecific asymmetric reproductive interference predicts the rate of species exclusion of MED by MEAM1. These findings not only reveal the importance of reproductive interference in the competitive interactions between the two invasive whiteflies as well as the detailed behavioural mechanisms, but also provide a valuable framework against which the effects of other factors mediating species exclusion can be explored.

Positive plant interactions have strong effects on plant diversity at several spatial scales, expanding species distribution under stressful conditions. We evaluated the joint effect of climate and grazing on the nurse effect of Croton wagneri, by monitoring several community attributes at two spatial scales: microhabitat and plant community. Two very close locations that only differed in grazing intensity were surveyed in an Ecuadorian dry scrub ecosystem. At each location, two 30 × 30-m plots were established at four altitudinal levels (1500, 2630, 1959 and 2100 m asl) and 40 microsites were surveyed in each plot. Croton wagneri acted as community hubs, increasing species richness and plant cover at both scales. Beneath nurses mean richness and cover values were 3.4 and 21.9%, and in open areas 2.3 and 4.5%, respectively. Magnitude of nurse effect was dependent on climate and grazing conditions. In ungrazed locations, cover increased and diversity reduced with altitude, while grazed locations showed the opposite trend. In ungrazed plots the interactions shifted from positive to negative with altitude, in grazed locations interactions remained positive. We conclude that the nurse effect is a key mechanism regulating community properties not only at microsite but also at the entire community scale.

Shade plots, simple visual representations of abundance matrices from multivariate species assemblage studies, are shown to be an effective aid in choosing an overall transformation (or other pre-treatment) of quantitative data for long-term use, striking an appropriate balance between dominant and less abundant taxa in ensuing resemblance-based multivariate analyses. Though the exposition is entirely general and applicable to all community studies, detailed illustrations of the comparative power and interpretative possibilities of shade plots are given in the case of two estuarine assemblage studies in south-western Australia: (a) macrobenthos in the upper Swan Estuary over a two-year period covering a highly significant precipitation event for the Perth area; and (b) a wide-scale spatial study of the nearshore fish fauna from five divergent estuaries. The utility of transformations of intermediate severity is again demonstrated and, with greater novelty, the potential importance seen of further mild transformation of all data after differential down-weighting (dispersion weighting) of spatially ‘clumped’ or ‘schooled’ species. Among the new techniques utilized is a two-way form of the RELATE test, which demonstrates linking of assemblage structure (fish) to continuous environmental variables (water quality), having removed a categorical factor (estuary differences). Re-orderings of sample and species axes in the associated shade plots are seen to provide transparent explanations at the species level for such continuous multivariate patterns.

There is little understanding of how large mammalian herbivores in Asia partition habitat and forage resources, and vary their diet and habitat selection seasonally in order to coexist. We studied an assemblage of four large herbivores, chital (Axis axis), sambar (Cervus unicolor), gaur (Bos gaurus) and Asian elephant (Elephas maximus), in the seasonal tropical forests of Bandipur and Mudumalai, South India, and tested predictions regarding the species’ seasonal diet browse : graze ratios, habitat selection and habitat-niche preference and overlap. Field data collected for the study included the seasonal variation in grass quality, the seasonal variation in δ13C in the species’ faeces and the seasonal variation in the species’ habitat selection and overlap using a grid-based survey. Results of the δ13C analyses showed that the chital was more of a grazer in the wet season (−17.9‰ to −21.6‰), but that it increased the proportion of browse in its diet in the dry season (−25.6‰ to −27.7‰); the gaur was a grazer for most of the year (−15.3‰ to −18.6‰); the sambar preferred to browse throughout the year (−21.1‰ to −30.4‰); and that the elephant was a mixed feeder (−14.2‰ to −21.4‰). Elephant habitat-niche breadth was high (0.53 in wet and 0.54 in dry) and overlapped equally with that of the other species in both seasons (0.39–0.94). The gaur had the most restricted habitat-niche breadth in both seasons (0.25 in wet and 0.28 in dry), and it switched from the moist deciduous habitat in the dry season to the dry deciduous habitat in the wet season. These results offer the first insights into the seasonal variation in browse : graze diet ratios and the habitat-niche overlap amongst the common largest-bodied mammalian herbivore species found in South India.

Seasonal changes in resource use and reproduction within a guild of nectar-feeding phyllostomid bats were studied between 2002 and 2004 in a west Mexican dry forest using mist-net captures and diet analysis over 82 nights during both dry and wet seasons. The local guild consisted of three resident species, Glossophaga soricina, Leptonycteris yerbabuenae, Musonycteris harrisoni, and of Anoura geoffroyi, which was mostly captured during the wet season. The proportion of L. yerbabuenae females more than doubled during the dry season. Diet was accessed by identifying the pollen collected from the bats' bodies and by analysis of faecal material. Bats used at least 28 different nectar plants over the year. In the dry season, 91.9% of all bats carried pollen while only 54.6% did so in the wet season. Bat individuals used the highest number of plant species during the dry season, mainly the cactus Pachycereus pecten-aboriginum, various Bombacaceae and the Capparaceae Cleome spinosa. Niche overlap was higher in the dry season than in the wet season. Musonycteris harrisoni and Leptonycteris yerbabuenae showed the largest overlap and both relied heavily on cactus flowers, whereas G. soricina supplemented its nectar diet with fruits. While reproductive females of most species were found only in the flower-rich dry season, G. soricina showed a bimodal reproductive pattern.