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Subfossil remains of the Quaternary megafauna from two Ukrainian natural history collections stored at Kaniv Nature Reserve and the National Museum of Natural History NAS of Ukraine were examined. Most of the bones were collected in 1965–1966, in the building pit and the gateway of the Kaniv hydroelectric power plant. The fauna is represented at least by ten taxa (Gulo gulo, Mammuthus trogonterii chosaricus, Mammuthus intermedius, Coelodonta antiquitatis, Megaloceros giganteus, Alces alces, Bison priscus, Cervus elaphus, Capra cf. ibex, and Equus ferus). Skeletal parts are represented mainly by skulls, long bones, horns, and tusks. Based on the species composition of proboscideans, at least part of the faunal assemblage is dated by the end of the Middle Pleistocene (Dnieper Stage = Saale, Warta, MIS 6), but majority of bones could be older or younger (Late Pleistocene and Holocene age) due to the alluvial origin of accumulation.

The Bering Land Bridge connecting North America and Eurasia was periodically exposed and inundated by oscillating sea levels during the Pleistocene glacial cycles. This land connection allowed the intermittent dispersal of animals, including humans, between Western Beringia (far north-east Asia) and Eastern Beringia (north-west North America), changing the faunal community composition of both continents. The Pleistocene glacial cycles also had profound impacts on temperature, precipitation, and vegetation, impacting faunal community structure and demography. While these palaeoenvironmental impacts have been studied in many large herbivores from Beringia (e.g., bison, mammoths, horses), the Pleistocene population dynamics of the diverse guild of carnivorans present in the region are less well understood, due to their lower abundances. In this study, we analyse mitochondrial genome data from ancient brown bears (Ursus arctos; n = 103) and lions (Panthera spp.; n = 39), two megafaunal carnivorans that dispersed into North America during the Pleistocene. Our results reveal striking synchronicity in the population dynamics of Beringian lions and brown bears, with multiple waves of dispersal across the Bering Land Bridge coinciding with glacial periods of low sea levels, as well as synchronous local extinctions in Eastern Beringia during Marine Isotope Stage 3. The evolutionary histories of these two taxa underscore the crucial biogeographic role of the Bering Land Bridge in the distribution, turnover, and maintenance of megafaunal populations in North America.

Proboscideans were keystone Cenozoic megaherbivores and present a highly relevant case study to frame the timing and magnitude of recent megafauna extinctions against long-term macroevolutionary patterns. By surveying the entire proboscidean fossil history using model-based approaches, we show that the dramatic Miocene explosion of proboscidean functional diversity was triggered by their biogeographical expansion beyond Africa. Ecomorphological innovations drove niche differentia- tion; communities that accommodated several disparate proboscidean species in sympatry became commonplace. The first burst of extinctions took place in the late Miocene, approximately 7 million years ago (Ma). Importantly, this and subsequent extinction trends showed high ecomorphological selectivity and went hand in hand with palaeoclimate dynamics. The global extirpation of proboscideans began escalating from 3 Ma with further extinctions in Eurasia and then a dramatic increase in African extinctions at 2.4 Ma. Overhunting by humans may have served as a final double jeopardy in the late Pleistocene after climate-triggered extinction trends that began long before hominins evolved suitable hunting capabilities., This work was supported by the Talent Attraction Program of the Madrid Government (no. 2017-T1/AMB5298), the German Research Foundation (AOBJ no. 637491) and the Academy of Finland (post-doctoral research fund no. 315691).

Dating bone collagen has been problematic in the Argentinean Pampas. Many bone samples do not have collagen or have poor preservation giving collagen of questionably quality, in many cases it is contaminated by humic substances. The combination of these factors has produced suspicious results, leading to the proposition of the Holocene survival in the region of the extinct Pleistocene megamammals such as the Megatherium Holocene ages from the Campo Laborde site. However, new dates from the same sample, purified from humates with XAD-2 resin, gave results of ~10,650 14C years BP. In this article, we apply different methodological procedures (chemical, geoarchaeological and taphonomic analysis) in order to reconstruct the formation at the Campo Laborde the site and identify the processes and agents that affected its chronology. The previously obtained Early Holocene ages of megafauna bones resulted from the interrelation of various factors as physical and chemical weathering, humification processes linked to pedogenesis, and diagenetic processes. In sum, they caused the degradation of collagen and the subsequent contamination by fulvic acids from the overlaying soil, which classic pretreatment techniques could not remove. We conclude that the obtained results do not support the Holocene survival of the megafauna in the Pampas.

Litter in the marine environment, in particular plastic, is a significant threat to marine megafauna. Cetaceans are known to ingest or become entangled in marine debris, likely impacting individuals and populations. Southeast Asia is a biodiversity hotspot and harbours a diverse cetacean assemblage. However, there are key knowledge gaps relating to the impact of litter in this region due the lack of experts to survey its vast coastlines. This study aims to address such gaps by using social media, gathering data from Facebook posts relating to cetacean strandings and litter across Southeast Asia between 2009 and 2019. Results show that at least 15 cetacean species have been negatively affected by litter, with ingestion most commonly affecting deep-diving species. Epipelagic and mesopelagic foragers were most vulnerable to entanglement. Davao in the Philippines was identified as a litter-related stranding hotspot. The Irrawaddy dolphin (Orcaella brevirostris) and pygmy sperm whale (Kogia breviceps) are particularly vulnerable to litter. The combination of social media and peer reviewed literature can help build a more complete picture of the spatial distribution of marine litter and the scale of the impact it has on cetacean populations. In this study we provide details of a valuable online tool for helping to understand the impact of marine litter on cetaceans and other charismatic species that are a focus of community engagement.

Climatic and environmental changes, as well as human action, have been cited as potential causes for the extinction of megafauna in South America at the end of the Pleistocene. Among megamammals lineages with Holarctic origin, only horses and proboscideans went extinct in South America during this period. This study aims to understand how the spatial extent of habitats suitable for Equus neogeus and Notiomastodon platensis changed between the last glacial maximum (LGM) and the middle Holocene in order to determine the impact that climatic and environmental changes had on these taxa. We used species distribution modeling to estimate their potential extent on the continent and found that both species occupied arid and semiarid open lands during the LGM, mainly in the Pampean region of Argentina, southern and northeastern Brazil, and parts of the Andes. However, when climate conditions changed from dry and cold during the LGM to humid and warm during the middle Holocene, the areas suitable for these taxa were reduced dramatically. These results support the hypothesis that climatic changes were a driving cause of extinction of these megamammals in South America, although we cannot rule out the impact of human actions or other potential causes for their extinction.

Most studies about benthic community use small-scale sampling methods focused on the infauna such as grabs or box-corers. The benthic data collected by scientific trawl surveys in all European waters, in the frame of the Common Fishery Policy Data Collection Multiannual Program, can be used to study the impact of large-scale fisheries such as trawling. However, the catchability of trawls is very dependent on the nature of the seabed as well as resulting ground-gear adaptations. Due to its non-destructive nature and its ability to focus on benthic macro-epifauna, towed video sampling appears to be a good alternative to monitor the impact of trawling on benthic communities. In the present work, we studied the influence of fishery induced seabed abrasion and video characteristics on nine indices, which can be used to monitor the effect of trawling on benthic communities, was studied. Among them, three indices specific to fishery effect detection based on biological traits appeared to be the best performing benthic indices with video data: modified-Trawling Disturbance Index, partial-Trawling Disturbance Index, and modified sensitivity index. The effectiveness of these indices to monitor the effect of trawling was evaluated and compared between trawl and video sampling. This work has highlighted that video sampling could be a good alternative, or at least a complementary method, to scientific trawling to monitor the effect of trawling on benthic communities in European waters.

Mutualism is a form of symbiosis whereby both parties benefit from the relationship. An example is cleaning symbiosis, which has been observed in terrestrial and marine environments. The most recognized form of marine cleaning symbiosis is that of cleaner fishes and their clients.Cleaner species set up cleaning stations on the reef, and other species seek out their services. However, it is not well understood how the presence of cleaning stations influence movements of large highly mobile species. We examined the role of cleaning stations as a driver of movement and habitat use in a mobile client species.Here, we used a combination of passive acoustic telemetry and in‐water surveys to investigate cleaning station attendance by the reef manta ray Mobula alfredi. We employed a novel approach in the form of a fine‐scale acoustic receiver array set up around a known cleaning area and tagged 42 rays. Within the array, we mapped structural features, surveyed the distribution of cleaner wrasse, and observed the habitat use of the rays.We found manta ray space use was significantly associated with blue‐streak cleaner wrasse Labroides dimidiatus distribution and hard coral substrate. Cleaning interactions dominated their habitat use at this site, taking precedence over other life history traits such as feeding and courtship.This study has demonstrated that cleaning symbiosis is a driver for highly mobile, and otherwise pelagic, species to visit inshore reef environments. We suggest that targeted and long‐term use of specific cleaning stations reflects manta rays having a long‐term memory and cognitive map of some shallow reef environments where quality cleaning is provided. We hypothesize that animals prefer cleaning sites in proximity to productive foraging regions., This study investigates the role of mutualism in determining site selection in marine megafauna. The aim was to determine the role of cleaning stations as a driver of movement and habitat use in a mobile client species. Through a combination of in‐water observations and a novel application of fine‐scale passive acoustic tracking, we demonstrated that cleaning symbiosis is a driver for highly mobile, and otherwise pelagic species to visit inshore reef environments. We suggest that targeted and long‐term use of specific cleaning stations reflects manta rays having a long‐term memory and cognitive map of some shallow reef environments where quality cleaning is provided. We hypothesize that animals preference cleaning sites in proximity to productive foraging regions.

Monitoring large marine mammals is challenging due to their low abundances in general, an ability to move over large distances and wide geographical range sizes.The distribution of the pygmy (Kogia breviceps) and dwarf (Kogia sima) sperm whales is informed by relatively rare sightings, which does not permit accurate estimates of their distribution ranges. Hence, their conservation status has long remained Data Deficient (DD) in the Red list of the International Union for Conservation of Nature (IUCN), which prevent appropriate conservation measures.Environmental DNA (eDNA) metabarcoding uses DNA traces left by organisms in their environments to detect the presence of targeted taxon, and is here proved to be useful to increase our knowledge on the distribution of rare but emblematic megafauna.Retrieving eDNA from filtered surface water provides the first detection of the Dwarf sperm whale (Kogia sima) around the remote Malpelo island (Colombia).Environmental DNA collected during oceanic missions can generate better knowledge on rare but emblematic animals even in regions that are generally well sampled for other taxa., Retrieving eDNA from filtered surface water provides the first detection of the Dwarf sperm whale (Kogia sima) around the remote Malpelo island (Colombia).

The many high-resolution tools that are uniquely applicable to specimens from the Quaternary period (the past ~2.5 Ma) provide an opportunity to cross-validate data and test hypotheses based on the morphology and distribution of fossils. Among these tools is palaeogenomics - the genome-scale sequencing of genetic material from ancient specimens - that can provide direct insight into ecology and evolution, potentially improving the accuracy of inferences about past ecological communities over longer timescales. Palaeogenomics has revealed instances of over- and underestimation of extinct diversity, detected cryptic faunal migration and turnover, allowed quantification of widespread sex biases and sexual dimorphism in the fossil record, revealed past hybridisation events and hybrid individuals, and has highlighted previously unrecognised routes of zoonotic disease transfer.

Seamounts and oceanic islands of the Chilean Exclusive Economic Zone at the intersection of the Nazca and Salas y Gómez ridges lie within one of the least explored areas in the world. The sparse information available, mainly for seamounts outside Chilean jurisdiction and shallow-water fauna of the Desventuradas Islands, suggests that the area is a hotspot of endemism. This apparent uniqueness of the fauna motivated the creation of the large Nazca-Desventuradas Marine Park (NDMP, ~ 300,000 km2) around the small islands San Felix and San Ambrosio in 2015. We report for the first time a detailed description of benthic microhabitats (i.e., centimeter to meter scale), macrohabitats (i.e., meter to kilometer-scale) and associated megafauna within the NDMP. Descriptions were based on analysis of fauna collected by trawling and ROV video observations from ~ 50 to 370 m depth. Rocky, coarse sand and silty sediment bottom habitats were observed at island slopes. In contrast, rocky and coarse sandy bottom habitats with a predominance of rhodoliths, thanatocoenosis, and other biogenic components were observed at seamounts. Mobile fauna and predators dominated the oceanic islands and nearby seamounts, whereas seamounts farther from the islands were dominated by sessile and hemisessile fauna that were mainly suspension and deposit feeders. Based on the register of 118 taxonomic units, our results provide an expanded and updated baseline for the benthic biodiversity of NDMP habitats, which seemed pristine, without evidence of trawling or anthropogenic debris.

The earliest appearance of elk/wapiti (Cervus canadensis) in eastern North America is not thoroughly documented due to the small number of directly dated remains. Until recently, no absolute dates on elk bone older than 10,000 14C yr BP (11,621 to 11,306 calibrated years (cal yr) BP) were known from this region. The partial skeleton of the Tope Elk was discovered in 2017 during commercial excavation of peat deposits from a small bog in southeastern Medina County, Ohio, United States. Subsequent examination of the remains revealed the individual to be a robust male approximately 8.5 years old at death. The large size of this individual is compared with late Holocene specimens and suggests diminution of elk since the late Pleistocene. Two accelerator mass spectrometry (AMS) radiocarbon assays on bone collagen samples taken from the scapula and metacarpal of this individual returned ages of 10,270 ± 30 14C yr BP (Beta-477478) (12,154 to 11,835 cal yr BP) and 10,260 ± 30 14C yr BP (Beta-521748) (12,144 to 11,830 cal yr BP), respectively. These results place Cervus canadensis in the terminal Pleistocene of the eastern woodlands and near the establishment of the mixed deciduous forest biome over much of the region. This early temporal placement also situates this early elk as closely following the last representatives of now-extinct megafauna such as the American mastodon (Mammut americanum) and contemporary with the Late Paleoindian inhabitants of the region.

Understanding predator–prey relationships is critical in ecology, but relatively challenging when investigating elusive marine megafauna. In this study, we document the presence of shark-inflicted ...

An extinct thermophile European water buffalo Bubalus murrensis was recorded in the interglacials of the Middle and Late Pleistocene in Central and Western Europe. The species was unknown after the Eemian Interglacial (c. 123 ka) there and have never been found in Eastern Europe. Here we report on an unexpected record of this exotic species in the center of East European Plain near the Kolomna town (Moscow Region) more than 110 millennia later, in the Bolling – Allerod warming of the Last glacial. The unique paleontological discovery of the last European water buffalo in the center of Eastern Europe occupied mainly by a cold adapted so-called ‘Mammoth fauna’ allow us to discuss this unusual occurrence in paleoenvironmental context and suggest the model of dispersal and final extinction of the species. Based on recent integrated studies, we show that the species could persist in the Ponto-Caspian region and then spread northwards during the last Late Pleistocene warming. Main factors of its extinction could be the rapid global climatic changes and strong regional paleoenvironmental instability as well as increasing activity of Upper Paleolithic hunters. The discovery is important in the context of the late Quaternary megafaunal extinctions and a recent phenomenon of global warming.

Records of Pleistocene reptiles are relatively well known in different countries. However, reptile fossil records of Pleistocene from Latin America are scarce and limited to presence data associated with records of megafauna remains. Taphonomic studies in Pleistocene reptiles are focused on finding out the origin of the paleontological remains; that is, if the remains found at a particular place correspond to organisms that lived and died there or if they were carried out and deposited there by water currents or predators. Pleistocene reptiles have been used as a proxy for qualitative paleoclimatic reconstructions of localities. In this study, we describe the fossil record of squamate reptiles from the Pleistocene of San Jose Buenavista (Puebla, Mexico), and the taphonomic relationship between them and the associated megafauna, as well as reconstruct the paleoclimate of the paleontological site in Central Mexico where the remains were found. We present the first Mexican Pleistocene record of Anolis and Storeria, the third fossil record of the alligator lizard Barisia sp. in Mexico, and the first North American Pleistocene record for the rattlesnake Crotalus triseriatus. The rattlesnake (C. triseriatus) was found inside the mandible of the American mastodon (Mammut americanum). This finding suggests that the mastodon remains were used as burrow by the rattlesnake during the Pleistocene. Paleoclimate was reconstructed using the Mutual Ecogeographic Range method, which uses the distribution and climate niche of the nearest extant representatives of the identified fossil taxa. A mean annual temperature of 13.91 ± 1.54 °C and an annual precipitation of 964.04 ± 316.82 mm were inferred for the locality. This suggests that the assemblage of fossil species found inhabited the locality during a glacial period.

Proboscideans arrived in South America from North America during the Great American Biotic Interchange, becoming one of the most representative animals of the megafauna that inhabited this continent throughout the Quaternary. In Colombia, the abundance of their remains contrasts with scarce scientific descriptions and publications. This paper identifies dental and postcranial proboscidean fossils from the Center and Northeast of Colombia. The fossil remains were identified as molars (six), a tusk, cervical vertebrae, and a distal part of the right humerus. The tusk was assigned to Notiomastodon platensis, while the other remains were assigned to Gomphotheriidae, with at least six individuals: two immatures, two subadults, and two older adults – mature and senile. Keywords: South America, megamammals, taxonomy, Gomphotheriidae, Notiomastodon platensis.

Elephants have profound effects on the functioning of the ecosystems they inhabit. Little is known, however, about the role of Asian elephants (Elephas maximus) as agents of seed dispersal in tropical rainforests of Southeast Asia, particularly in the Sundaland region. Sundaic forests are peculiar in their phenology, with supra-annual and highly irregular episodes of mast fruiting. Here I present a long-term (73-month) monitoring of the seeds dispersed by elephants in dipterocarp forests of northern Peninsular Malaysia. I conducted monthly dung surveys in two mineral licks (11.3 km apart) frequently visited by elephants. Additionally, I recorded haphazard observations of seeds and seedlings in elephant dung. I recorded a minimum of 45 morphospecies from at least 25 plant families dispersed by elephants. Elephant seed dispersal varies spatially, with only 39.4% of the morphospecies dispersed at both sites (Jaccard dissimilarity index = 0.45). Temporally, elephants dispersed seeds in sporadic pulses in terms of abundance and diversity, without any apparent seasonality (seeds appeared in 19.1 % of 1,284 dung piles and 49.3 % of 73 months sampled). Around 14 morphospecies exhibited the two types of megafaunal syndrome traits defined by Guimaraes et al. (2008). However, another 11 morphospecies were found to conform to a Type 3 trait; species with large fruits and moderately large (> 1.5 cm) seeds in moderately large numbers (> 15). This makes the total of 24 morphospecies exhibiting megafaunal syndrome traits. However, the current definition is over simplified, and a new definition is needed that expands beyond physical fruit traits. Over half (53%) of the plants dispersed by elephants exhibit the megafaunal dispersal syndrome, suggesting a higher level of specialized elephant-plant seed dispersal interactions than previously assumed in Asia. Sundaland’s forests are undergoing a rapid loss of their rich megafaunal assemblages, with profound and long-term consequences for their function.

The study of faecal samples to reconstruct the diets and habitats of extinct megafauna has traditionally relied on pollen and macrofossil analysis. DNA metabarcoding has emerged as a valuable tool to complement and refine these proxies. While published studies have compared the results of these three proxies for sediments, this comparison is currently lacking for permafrost preserved mammal faeces. Moreover, most metabarcoding studies have focused on a single plant-specific DNA marker region. In this study, we target both the commonly used chloroplast trnL P6 loop as well as nuclear ribosomal ITS (nrITS). The latter can increase taxonomic resolution of plant identifications but requires DNA to be relatively well preserved because of the target length (∼300–500 bp). We compare DNA results to pollen and macrofossil analyses from permafrost and ice-preserved faeces of Pleistocene and Holocene megafauna. Samples include woolly mammoth, horse, steppe bison as well as Holocene and extant caribou. Most plant identifications were found using DNA, likely because the studied faeces contained many vegetative remains that could not be identified using macrofossils or pollen. Several taxa were, however, identified to lower taxonomic levels uniquely with macrofossil and pollen analysis. The nrITS marker provides species level taxonomic resolution for commonly encountered plant families that are hard to distinguish using the other proxies (e.g. Asteraceae, Cyperaceae and Poaceae). Integrating the results from all proxies, we are able to accurately reconstruct known diets and habitats of the extant caribou. Applying this approach to the extinct mammals, we find that the Holocene horse and steppe bison were not strict grazers but mixed feeders living in a marshy wetland environment. The mammoths showed highly varying diets from different non-analogous habitats. This confirms the presence of a mosaic of habitats in the Pleistocene ‘mammoth steppe’ that mammoths could fully exploit due to their flexibility in food choice.

The extinction of megafauna in the Neotropics is thought to have reduced the potential of large seeds to be dispersed over long distances by endozoochory (ingestion by animals), but some seed dispersal systems have not been considered. We describe the role of oilbirds (Steatornis caripensis) as seed dispersers, in terms of seed width and dispersal distance (using GPS tracking devices), and we compare with data reported for other animals. Oilbirds dispersed seeds up to 29 mm wide, with a mean dispersal distance of 10.1 km (range 0–47.6 km). Some components of seed dispersal by oilbirds are outliers compared to that of other frugivores, such as the relationship between maximum seed width and body weight (however, few other extant specialized frugivores are also outliers). Estimates of mean dispersal distance by oilbirds are the largest reported, and we confirm that some living frugivores currently fulfil roles of seed dispersers and ecosystem services previously assumed to be only performed by extinct species.

A new Pleistocene site in the Pabbi Hills of Pakistan, and deposits to the east near Bhimbar provide important additions to the Upper Siwalik fauna of South Asia. The mammalian fauna of 10 species from Panjan Sher Shahana at the southwestern tip of the Pabbi Hills is a rich mammalian assemblage dating to the early to Middle Pleistocene of the Upper Siwalik Subgroup. The Panjan Sher Shahana assemblage shows strong resemblance to other Pleistocene faunas of the Siwalik Group from the Indian subcontinent. The new site is dominated by Bovidae and Equus. Among megafauna, two species of Elephas, commonly found in the Upper Siwaliks, are associated with the uncommon Stegodon in Pabbi Hills. These and other elements of the Panjan Sher Shahana fauna are treated briefly here. The Late Neogene deposits of Bhimbar, 30 km east of Jhelum, appear to represent a similar succession equivalent to the Pleistocene (“Pinjor”) fauna and produce important new elements, including a rare record of the bamboo rat Anepsirhizomys opdykei.

The Arctic sea-ice-scape is rapidly transforming. Increasing light penetration will initiate earlier seasonal primary production. This earlier growing season may be accompanied by an increase in ice algae and phytoplankton biomass, augmenting the emission of dimethylsulfide and capture of carbon dioxide. Secondary production may also increase on the shelves, although the loss of sea ice exacerbates the demise of sea-ice fauna, endemic fish and megafauna. Sea-ice loss may also deliver more methane to the atmosphere, but warmer ice may release fewer halogens, resulting in fewer ozone depletion events. The net changes in carbon drawdown are still highly uncertain. Despite large uncertainties in these assessments, we expect disruptive changes that warrant intensified long-term observations and modelling efforts., info:eu-repo/semantics/published

Understanding how threatened species are distributed in space and time can have direct applications to conservation planning. However, implementing standardized methods to monitor populations of wide-ranging species is often expensive and challenging. In this study, we used baited remote underwater video stations (BRUVS) to quantify elasmobranch abundance and distribution patterns across a gradient of protection in the Pacific waters of Costa Rica. Our BRUVS survey detected 29 species, which represents 54% of the entire elasmobranch diversity reported to date in shallow waters (

Plastic pollution is increasing rapidly throughout the world’s oceans and is considered a major threat to marine wildlife and ecosystems. Although known to cause lethal or sub-lethal effects to vulnerable marine megafauna, population-level impacts of plastic pollution have not been thoroughly investigated. Here, we compiled and evaluated information from peer-reviewed studies that reported deleterious individual-level effects of plastic pollution on air-breathing marine megafauna (i.e. seabirds, marine mammals, and sea turtles) worldwide, highlighting those that assessed potential population-level effects. Lethal and sub-lethal individual-level effects included drowning, starvation, gastrointestinal tract damage, malnutrition, physical injury, reduced mobility, and physiological stress, resulting in reduced energy acquisition and assimilation, compromised health, reproductive impairment, and mortality. We found 47 studies published between 1969 and 2020 that considered population-level effects of plastic entanglement (n = 26), ingestion (n = 19), or both (n = 2). Of these, 7 inferred population-level effects (n = 6, entanglement; n = 1, ingestion), whereas 19 lacked evidence for effects (n = 12, entanglement; n = 6, ingestion; n = 1, both). However, no study in the past 50 yr reported direct evidence of population-level effects. Despite increased interest in and awareness of the presence of plastic pollution throughout the world’s oceans, the extent and magnitude of demographic impacts on marine megafauna remains largely unassessed and therefore unknown, in contrast to well-documented effects on individuals. Addressing this major assessment gap will allow researchers and managers to compare relative effects of multiple threats—including plastic pollution—on marine megafauna populations, thus providing appropriate context for strategic conservation priority-setting.

We studied ice algae utilization by benthic fauna from the northern Bering and Chukchi Seas using highly branched isoprenoid (HBI) biomarkers. We assessed whether various food acquisition strategies influence the observed HBI signatures. The proportion of phytoplankton to ice algae-sourced HBIs was determined through the H-Print approach that is presumed to reflect the percentage of sea ice organic carbon (iPOC) incorporated into tissues, relative to phytoplankton organic carbon. Cluster analysis separated 3 groups based on location and feeding strategy that were significantly influenced by annual sea ice persistence. Ice algae utilization was most significant in the northeast Chukchi Sea, where seasonal sea ice was present the longest. General feeding strategy was determined to be a significant factor in the degree of ice algae utilization. Predominant deposit feeders (both surface and subsurface) used more ice algae relative to suspension feeders. Organic carbon incorporated by predominant suspension feeders was primarily phytoplankton-based. The vast majority of all organisms sampled (~90%) incorporated a measurable quantity of iPOC. Sipunculids and brittle stars had the highest relative dependence on ice algae, while other taxa displayed plastic dietary responses, including the suspension/surface deposit feeder Macoma calcarea. This study indicates that ice algae are widely utilized in Pacific Arctic benthic food webs, but most benthic organisms displayed flexibility in consuming the available food sources. The elevated utilization of ice algae by deposit feeders may prove to be a disadvantage for these organisms if they cannot adapt to the ongoing decline of iPOC as seasonal sea ice declines.

The Coc Muoi fauna provides a good example of the type of tropical mammalian communities that existed in northern Vietnam during the late Middle Pleistocene. The first results of the analysis of hypoplasia indicated that rhinoceroses and wild cattle were exposed to multiple physiological and psychological stress events specific to age [ Bacon et al., 2018 . A rhinocerotid-dominated megafauna at the MIS6-5 transition: The late Middle Pleistocene Coc Muoi assemblage, Lang Son province, Vietnam. Quat. Sci. Rev. 186, 123–141]. In this paper, we aim to supplement the study of hypoplasia in the orangutans (Pongo) from Coc Muoi and, more widely, from different Pleistocene faunas. To address this issue, we conducted a macroscopic analysis of linear enamel hypoplasia [LEH] on Pongo from three collections: Coc Muoi (148–117 ka), Duoi U'Oi (70–60 ka), and Tham Khuyen (>475 ka). Such comparative analysis based on isolated teeth is constrained by numerous biases including: the small datasets; the differential representation of tooth types; the difficulty in distinguishing first from second molars; the small number of individuals [MNI]; the differential representation of males versus females. The data analysis has been divided into two parts: (1) an analysis of the frequency and expression of LEH on incisors, premolars, and molars (three sites), and (2) an analysis of the frequency and expression of LEH on a set of canines (Tham Khuyen). We used a reference sample composed of 17 adult and 10 immature Pongo individuals to determine the age range of fossil Pongo individuals, at the time of the defects. Results show that hypoplasia was a common phenomenon in Pleistocene Pongo: two individuals at Coc Muoi; 2 out of 3 individuals at Duoi U’Oi; and 4 out of 6 individuals at Tham Khuyen. They experienced multiple stresses between ∼2 and 5 years of age, a period of great vulnerability for immature individuals. The occurrence of accentuated lines of hypoplasia on canine crowns of Tham Khuyen suggests a greater intensity of the stressor, in a time range consistent with the long dietary and behavioral transition of the weaning. In terms of paleoecology, Pleistocene orangutans from the Asian mainland could survive in different environmental conditions than those they occupy today. Various sources (archaeozoology, geological context, and ecology of wild populations), suggest that they might have been larger apes than extant orangutans, living in limestone forests on hills and tower karsts.

One of the most striking human impacts on global biodiversity is the ongoing depletion of large vertebrates from terrestrial and aquatic ecosystems. Recent work suggests this loss of megafauna can affect processes at biome or Earth system scales with potentially serious impacts on ecosystem structure and function, ecosystem services, and biogeochemical cycles. We argue that our contemporary approach to biodiversity conservation focuses on spatial scales that are too small to adequately address these impacts. We advocate a new global approach to address this conservation gap, which must enable megafaunal populations to recover to functionally relevant densities. We conclude that re-establishing biome and Earth system functions needs to become an urgent global priority for conservation science and policy., Highlights The loss of large vertebrates (megafauna) from the world’s ecosystems has been occurring throughout human history. Emerging evidence suggests these losses can have dramatic impacts on ecological functions, including the near collapse of biogeochemical cycles at biome and Earth system scales. Although the biodiversity conservation community increasingly recognises the need to restore ecological functions at landscape scales, it currently operates at scales that are too small to adequately address the functional consequences of megafaunal losses at biome and earth system scales. Re-establishing biome and Earth system functions needs to become a global priority for the biodiversity conservation community, and we will need a new global initiative to deliver this.

Extinctions stemming from environmental change often trigger trophic cascades and coextinctions. Bottom-up cascades occur when changes in the primary producers in a network elicit flow-on effects to higher trophic levels. However, it remains unclear what determines a species' vulnerability to bottom-up cascades and whether such cascades were a large contributor to the megafauna extinctions that swept across several continents in the Late Pleistocene. The pathways to megafauna extinctions are particularly unclear for Sahul (landmass comprising Australia and New Guinea), where extinctions happened earlier than on other continents. We investigated the potential role of bottom-up trophic cascades in the megafauna extinctions in Late Pleistocene Sahul by first developing synthetic networks that varied in topology to identify how network position (trophic level, diet breadth, basal connections) influences vulnerability to bottom-up cascades. We then constructed pre-extinction (-80 ka) network models of the ecological community of Naracoorte, south-eastern Sahul, to assess whether the observed megafauna extinctions could be explained by bottom-up cascades. Synthetic networks showed that node vulnerability to bottom-up cascades decreased with increasing trophic level, diet breadth and basal connections. Extinct species in the Naracoorte community were more vulnerable overall to these cascades than were species that survived. The position of extinct species in the network - tending to be of low trophic level and therefore having relatively narrow diet breadths and fewer connections to plants - made them vulnerable. However, these species also tended to have few or no predators, a network-position attribute that suggests they might have been particularly vulnerable to new predators. Together, these results suggest that trophic cascades and naivety to predators could have contributed to the megafauna extinction event in Sahul.

Deep learning has become a key tool for the automated monitoring of animal populations with video surveys. However, obtaining large numbers of images to train such models is a major challenge for rare and elusive species because field video surveys provide few sightings. We designed a method that takes advantage of videos accumulated on social media for training deep-learning models to detect rare megafauna species in the field. We trained convolutional neural networks (CNNs) with social media images and tested them on images collected from field surveys. We applied our method to aerial video surveys of dugongs (Dugong dugon) in New Caledonia (southwestern Pacific). CNNs trained with 1303 social media images yielded 25% false positives and 38% false negatives when tested on independent field video surveys. Incorporating a small number of images from New Caledonia (equivalent to 12% of social media images) in the training data set resulted in a nearly 50% decrease in false negatives. Our results highlight how and the extent to which images collected on social media can offer a solid basis for training deep-learning models for rare megafauna detection and that the incorporation of a few images from the study site further boosts detection accuracy. Our method provides a new generation of deep-learning models that can be used to rapidly and accurately process field video surveys for the monitoring of rare megafauna.El aprendizaje profundo se ha convertido en una importante herramienta para el monitoreo automatizado de las poblaciones animales con video-censos. Sin embargo, la obtención de cantidades abundantes de imágenes para preparar dichos modelos es un reto primordial para las especies elusivas e infrecuentes porque los video-censos de campo proporcionan pocos avistamientos. Diseñamos un método que aprovecha los videos acumulados en las redes sociales para preparar a los modelos de aprendizaje profundo para detectar especies infrecuentes de megafauna en el campo. Preparamos algunas redes neurales convolucionales con imágenes tomadas de las redes sociales y las pusimos a prueba con imágenes tomadas en los censos de campo. Aplicamos nuestro método a los censos aéreos en video de dugongos (Dugong dugon) en Nueva Caledonia (Pacífico sudoccidental). Las redes neurales convolucionales preparadas con 1,303 imágenes de las redes sociales produjeron 25% de falsos positivos y 38% de falsos negativos cuando las probamos en video-censos de campo independientes. La incorporación de un número pequeño de imágenes tomadas en Nueva Caledonia (equivalente al 12% de las imágenes de las redes sociales) dentro del conjunto de datos usados en la preparación dio como resultado una disminución de casi el 50% en los falsos negativos. Nuestros resultados destacan cómo y a qué grado las imágenes recolectadas en las redes sociales pueden ofrecer una base sólida para la preparación de modelos de aprendizaje profundo para la detección de megafauna infrecuente. También resaltan que la incorporación de unas cuantas imágenes del sitio de estudio aumenta mucho más la certeza de detección. Nuestro método proporciona una nueva generación de modelos de aprendizaje profundo que pueden usarse para procesar rápida y acertadamente los video-censos de campo para el monitoreo de megafauna infrecuente.

Aim: Connectivity among ecosystems is necessary to sustain ecological processes that promote biodiversity, community stability and ecosystem resilience, such as organism and nutrient dispersal. Along with human land use and habitat fragmentation, connectivity can also be affected by faunal changes. Here, we address this issue by studying how human-driven late Quaternary extinctions and extirpations of terrestrial mammals have affected the movement capacity of assemblages, an estimate of the potential connectivity among ecosystems promoted by wildlife. Location: Global. Time period: Late Pleistocene to the Anthropocene. Major taxa studied: All 4,395 (4,073 extant and 322 extinct) terrestrial mammals alive in the Late Pleistocene. Methods: We combined macroecological estimates of home range size with range maps of current and natural geographical distributions of species to investigate how human pressure has modified natural movement capacity of terrestrial assemblages and how movement capacity will respond to future extinction and rewilding scenarios. Results: Our results showed that 74% of average and 83% of maximum movement capacity of Late Pleistocene mammal assemblages has been lost owing to prehistorical and historical extinctions and extirpations. We also found that movement capacity will decrease further if current extinction trajectories are not averted. However, our results showed that current average and maximum movement capacity can be restored to twice their current values under a full rewilding scenario and that average, but not maximum movement capacity, will increase under a conservative rewilding scenario, that is, without restoring the largest megafauna most likely to cause major human–wildlife conflicts. Main conclusions: Prehistorical and historical losses of megafauna have caused severe decreases in movement capacity of mammal assemblages, hence large reductions in ecosystem connectivity. Reintroductions can partly restore biotic connectivity, especially when the largest megafauna are also restored. However, natural levels of movement capacity cannot be recovered fully without including ecological replacements for extinct species in rewilding efforts.

1. The mahseer (Tor spp.) fishes of South and Southeast Asia are iconic megafaunal species that are highly valued by recreational anglers. Knowledge on their populations is limited due to the challenges associated with sampling these large bodied fishes (>50kg) in remote monsoonal rivers. Despite its global iconic status among recreational anglers, the hump-backed mahseer of South India’s River Cauvery lacked a valid scientific name and was on a trajectory towards extinction until its rapidly declining population status was established by analyses of angler catch records. 2. Angling records from 1998 to 2012 revealed that mahseer catch rates had increased in the period. The resulting publication in Aquatic Conservation (AQC) highlighted the positive role of catch-and-release angling in providing information on data-poor species. However, further analyses revealed these catches comprised of not one but two distinct phenotypes. Prior to 1993, all mahseer captured were hump-backed; since then, a blue-fin phenotype appeared in catches and subsequently dominated them. These results triggered further studies that revealed the hump-backed mahseer was the endemic Tor remadevii and the blue-fin was the invasive Tor khudree that had been introduced in 1976 and then stocked periodically from hatcheries. 3. The initial AQC publication successfully demonstrated the high value of organised angling as a monitoring tool for data-poor fishes and its application to assessing the temporal population patterns of large bodied fishes in monsoonal rivers. It was also the catalyst for initiating subsequent studies on T. remadevii that, in entirety, enabled its recent assessment as ‘Critically Endangered’ on the IUCN Red List. In the absence of the AQC paper, and the subsequent studies it triggered, it is highly probable that the species would have remained on a trajectory towards rapid extinction. Instead, the first major steps to safeguarding its future have been taken.

Resilient landscapes have helped maintain terrestrial biodiversity during periods of climatic and environmental change. Identifying the tempo and mode of landscape transitions and the drivers of landscape resilience is critical to maintaining natural systems and preserving biodiversity given today's rapid climate and land use changes. However, resilient landscapes are difficult to recognize on short time scales, as perturbations are challenging to quantify and ecosystem transitions are rare. Here we analyze two components of North American landscape resilience over 20,000 years: residence time and recovery time. To evaluate landscape dynamics, we use plant biomes, preserved in the fossil pollen record, to examine how long a biome type persists at a given site (residence time) and how long it takes for the biome at that site to reestablish following a transition (recovery time). Biomes have a median residence time of only 230-460 years. Only 64% of biomes recover their original biome type, but recovery time is 140-290 years. Temperatures changing faster than 0.5°C per 500 years result in much reduced residence times. Following a transition, biodiverse biomes reestablish more quickly. Landscape resilience varies through time. Notably, short residence times and long recovery times directly preceded the end-Pleistocene megafauna extinction, resulting in regional destabilization, and combining with more proximal human impacts to deliver a one-two punch to megafauna species. Our work indicates that landscapes today are once again exhibiting low resilience, foreboding potential extinctions to come. Conservation strategies focused on improving both landscape and ecosystem resilience by increasing local connectivity and targeting regions with high richness and diverse landforms can mitigate these extinction risks.

The Revillagigedo Archipelago National Park is the largest no-take Marine Protected Area in North America and it is essential for the conservation of globally endangered marine megafauna, including cetaceans, sea birds and cartilaginous fishes. The present paper reports the occurrence of 28 chondrichthyan species, including 19 sharks, seven batoids and two chimaeras in the Revillagigedo Archipelago, comprising eight new records and a brief revision of confirmed species to date.

Many marine animals aggregate seasonally at predictable locations to exploit their prey in oligotrophic environments, making them vulnerable to human disturbance. The foraging strategies and habitats of manta rays and Stenella spp. in the Solor waters were largely unknown, despite the importance of this information for their effective management, e.g. through the establishment of marine protected areas in this region. Over the last few decades, the use of foraging habitat models in describing the foraging strategy and delineating the predicted habitats has grown in popularity. However, most of these studies have relied on remotely sensed data such as sea surface chlorophyll‐a to estimate prey distribution. Very few studies have used the distribution of in situ prey, which is that closer to the trophic level of modelled species, although such a strategy would improve model performance. The study compares foraging habitat model performance for manta rays and Stenella spp. in the waters of Solor using remotely sensed sea surface chlorophyll‐a concentrations and in situ zooplankton biomass as proxies for prey quantities and distribution. A Maximum Entropy model that integrated species sightings with environmental predictors was used to quantify the importance of predictors in explaining habitat preference and distribution of manta rays and Stenella spp. and to compare model performance and predict foraging habitats. Results indicate that the use of prey proxy closer to the trophic level of examined species improve model performance, ecological explanations, and spatial predictions. The zooplankton biomass distribution performed much better in explaining the manta rays' habitats compared to that of Stenella spp., indicating that a trophic level gap might influence the zooplankton's ability to predict foraging habitats of Stenella spp. This study highlights the importance of integrating foraging habitat models into marine protected area design to ensure the effectiveness of species management.

Oxygen decline poses increasing risks to global shelf communities. This study was conducted to measure species oxygen exposures in situ and to assess risks of low oxygen based on the hypothesis that species risk varies spatially and is dependent on the interaction of shelf oxygen dynamics with habitat pattern, species mobility, and tolerance to low oxygen. Here, we report concomitant observations of oxygen, depth, and habitat for the most common benthic and epibenthic megafauna on the southern California shelf (30–125 m). The study was conducted when oxygen concentrations were the lowest observed within the previous 30 years off southern California (2012–2014), yet hypoxic conditions (

A growing body of literature proposes that our ancestors contributed to large mammal extinctions in Africa long before the appearance ofHomo sapiens, with some arguing that premodern hominins (e.g.,Homo erectus) triggered the demise of Africa's largest herbivores and the loss of carnivoran diversity. Though such arguments have been around for decades, they are now increasingly accepted by those concerned with biodiversity decline in the present-day, despite the near complete absence of critical discussion or debate. To facilitate that process, here we review ancient anthropogenic extinction hypotheses and critically examine the data underpinning them. Broadly speaking, we show that arguments made in favor of ancient anthropogenic extinctions are based on problematic data analysis and interpretation, and are substantially weakened when extinctions are considered in the context of long-term evolutionary, ecological, and environmental changes. Thus, at present, there is no compelling empirical evidence supporting a deep history of hominin impacts on Africa's faunal diversity.

A taphonomic comparison among ten Quaternary tank deposits bearing megafauna remains in northeastern Brazil allowed the identification of four regional-scale taphonomic aspects controlled by climate seasonality: differential preservation of mega-mammal bones, poor physical integrity, spatial resolution (local) and time averaging (104 years). Sedimentary aspects, such as the high degree of packing of fossiliferous layer, indicate conditions of low clastic detrital sediment input in arid conditions. The correlation among geochronological data of tank deposits and paleoclimatic curves of northeastern Brazil suggest that the climate was arid/semi-arid characterized by seasonality between dry and rainy periods. Thus, we postulate the succession of the two paleoenvironmental and paleoecological scenarios during the late Quaternary affecting the formation of fossiliferous tank deposits: (i) the intensity and duration of arid periods led animals to search for water and food, and consequently, concentration and death near these water sources; and (ii) in the rainy season, carcasses, disarticulated and fragmented bones around these water sources were transported and accumulated through high-energy tractive flows, reworking previously buried skeletal material.

Background Argos satellite telemetry is used globally to track terrestrial and aquatic megafauna, yet the accuracy of this system has been described empirically only for a limited number of species. We used Argos-linked archival tags with Fastloc GPS deployed on free-ranging sperm (Physeter macrocephalus), blue (Balaenoptera musculus), and fin (B. physalus) whales to derive empirical estimates of Argos location errors for these species, examine possible behavior-related differences, and test the effect of incorporating species-specific error parameters on performance of a commonly used movement model. Results Argos location errors for blue and fin whale tags were similar and were combined (n = 1712 locations) for comparison against sperm whale tags (n = 1206 locations). Location error magnitudes for tags attached to sperm whales were significantly larger than blue/fin whale tags for almost all Argos location classes (LC), ranging from 964 m versus 647 m for LC 3, respectively, to 10,569 m versus 5589 m for LC B, respectively. However, these differences were not seen while tags floated at the surface after release. Sperm whale tags were significantly colder than ambient temperature when surfacing from a dive, compared to blue/fin whale tags (16.9 °C versus 1.3 °C, respectively) leading to larger changes in tag temperature during post-dive intervals. The increased rate of tag temperature change while at the surface was correlated to increased error magnitude for sperm whales but not blue/fin whales. Movement model performance was not significantly improved by incorporating species-specific error parameters. Conclusions Location accuracy estimates for blue/fin whales were within the range estimated for other marine megafauna, but were higher for sperm whales. Thermal inertia from deep, long-duration dives likely caused transmission frequency drift and greater Argos location error in sperm whales, as tags warmed at the surface during post-dive intervals. Thus, tracks of deep-diving species may be less accurate than for other species. However, differences in calculated error magnitude between species were less than typical scales of movement and had limited effect on movement model performance. Therefore, broad-scale interpretation of Argos tracking data will likely be unaffected, although fine-scale interpretation should be made with more caution for deep-diving species inhabiting warm regions.

Drones deployed to monitor endangered species often crash. These crashes teach us that using drones for conservation is a contingent practice ensnaring humans, technologies, and animals. This article advances a crash theory in which pilots, conservation drones, and endangered megafauna are relata, or related actants, that intra-act, cocreating each other and a mutually constituted phenomena. These phenomena are entangled, with either reciprocal dependencies or erosive entrapments. The crashing of conservation drones and endangered species requires an ethics of care, repair, or reworlding. Diffractions, disruptions that expose difference, result from crashes and reveal the precarious manner by which technologies, laws, and discourses bring nature and culture together. To support crash theory, this article presents three ethnographic cases. A drone crash in the United Kingdom near white rhinoceroses while building machine learning training data exhibits the involvement of the electromagnetic spectrum; the threat of crashes in the Pacific Northwest near Puget Sound orcas discloses the impacts of drone laws; and drone crashes in Sri Lanka among Asian elephants presents the problems of technoliberal ideals around programming natural worlds. Throughout the article, a methodology is developed, parallelism, which attends to the material similarities in lateral phenomena.

Archaeologists have long subjected Clovis megafauna kill/scavenge sites to the highest level of scrutiny. In 1987, a Columbian mammoth (Mammuthus columbi) was found in spatial association with a small artifact assemblage in Converse County, Wyoming. However, due to the small tool assemblage, limited nature of the excavations, and questions about the security of the association between the artifacts and mammoth remains, the site was never included in summaries of human-killed/scavenged megafauna in North America. Here we present the results of four field seasons of new excavations at the La Prele Mammoth site that confirm the presence of an associated cultural occupation based on geologic context, artifact attributes, spatial distributions, protein residue analysis, and lithic microwear analysis. This new work identified a more extensive cultural occupation including the presence of multiple discrete artifact clusters in close proximity to the mammoth bone bed. This study confirms the presence of a second Clovis mammoth kill/scavenge site in Wyoming and shows the value in revisiting proposed terminal Pleistocene kill/scavenge sites.

Lions are one of the world’s most iconic megafauna, yet little is known about their temporal and spatial demographic history and population differentiation. We analyzed a genomic dataset of 20 specimens: two ca. 30,000-y-old cave lions (Panthera leo spelaea), 12 historic lions (Panthera leo leo/Panthera leo melanochaita) that lived between the 15th and 20th centuries outside the current geographic distribution of lions, and 6 present-day lions from Africa and India. We found that cave and modern lions shared an ancestor ca. 500,000 y ago and that the 2 lineages likely did not hybridize following their divergence. Within modern lions, we found 2 main lineages that diverged ca. 70,000 y ago, with clear evidence of subsequent gene flow. Our data also reveal a nearly complete absence of genetic diversity within Indian lions, probably due to well-documented extremely low effective population sizes in the recent past. Our results contribute toward the understanding of the evolutionary history of lions and complement conservation efforts to protect the diversity of this vulnerable species., S.J.O, was supported, in part, by St. Petersburg State University (Genome Russia Grant no. 1.52.1647.2016). T.M.-B. is supported by funding from BFU2017-86471-P (MINECO/FEDER, UE), Howard Hughes International Early Career, Obra Social “La Caixa” and Secretaria d’Universitats i Recerca and Centres de Recerca de Catalunya (CERCA) Programme del Departament d’Economia i Coneixement de la Generalitat de Catalunya (GRC 2017 SGR 880). We also acknowledge European Research Council (ERC) Consolidator Award 681396-Extinction Genomics to M.T.P.G. and Marie-Sklodowska Curie Fellowship 298820 “SIMBA” to R.B. for their generous funding.

Explanations for the Upper Pleistocene extinction of megafauna from Sahul (Australia and New Guinea) remain unresolved. Extinction hypotheses have advanced climate or human-driven scenarios, in spite of over three quarters of Sahul lacking reliable biogeographic or chronologic data. Here we present new megafauna from north-eastern Australia that suffered extinction sometime after 40,100 (±1700) years ago. Megafauna fossils preserved alongside leaves, seeds, pollen and insects, indicate a sclerophyllous forest with heathy understorey that was home to aquatic and terrestrial carnivorous reptiles and megaherbivores, including the world’s largest kangaroo. Megafauna species diversity is greater compared to southern sites of similar age, which is contrary to expectations if extinctions followed proposed migration routes for people across Sahul. Our results do not support rapid or synchronous human-mediated continental-wide extinction, or the proposed timing of peak extinction events. Instead, megafauna extinctions coincide with regionally staggered spatio-temporal deterioration in hydroclimate coupled with sustained environmental change., The causes of the Upper Pleistocene megafauna extinction in Australia and New Guinea are debated, but fossil data are lacking for much of this region. Here, Hocknull and colleagues report a new, diverse megafauna assemblage from north-eastern Australia that persisted until ~40,000 years ago.

Among the several fossils of South American tayassuids, it is remarkable the presence of a well-preserved skull from southern Brazil (Chui Creek, Santa Vitoria do Palmar, Santa Vitoria Formation). ...

Made available in DSpace on 2020-12-12T02:39:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-01 The Late Quaternary extinctions of megafauna (defined as animal species > 44.5 kg) reduced the dispersal of seeds and nutrients, and likely also microbes and parasites. Here we use body-mass based scaling and range maps for extinct and extant mammal species to show that these extinctions led to an almost seven-fold reduction in the movement of gut-transported microbes, such as Escherichia coli (3.3–0.5 km2 d−1). Similarly, the extinctions led to a seven-fold reduction in the mean home ranges of vector-borne pathogens (7.8–1.1 km2). To understand the impact of this, we created an individual-based model where an order of magnitude decrease in home range increased maximum aggregated microbial mutations 4-fold after 20 000 yr. We hypothesize that pathogen speciation and hence endemism increased with isolation, as global dispersal distances decreased through a mechanism similar to the theory of island biogeography. To investigate if such an effect could be found, we analysed where 145 zoonotic diseases have emerged in human populations and found quantitative estimates of reduced dispersal of ectoparasites and fecal pathogens significantly improved our ability to predict the locations of outbreaks (increasing variance explained by 8%). There are limitations to this analysis which we discuss in detail, but if further studies support these results, they broadly suggest that reduced pathogen dispersal following megafauna extinctions may have increased the emergence of zoonotic pathogens moving into human populations. School of Informatics Computing and Cyber Systems Northern Arizona Univ. Dept of Biological and Environmental Sciences Univ. of Gothenburg Gothenburg Global Biodiversity Centre Dept of Biological Sciences Northern Arizona Univ. Center for Biodiversity Dynamics in a Changing World (BIOCHANGE) Dept of Biology Aarhus Univ. Section for Ecoinformatics and Biodiversity Dept of Biology Aarhus Univ. Inst. de Biociências Depto de Ecologia Univ. Estadual Paulista (UNESP) Univ. of Miami Dept of Biology Inst. de Biociências Depto de Ecologia Univ. Estadual Paulista (UNESP)

One major challenge in the study of late-Quaternary extinctions (LQEs) is providing better estimates of past megafauna abundance. To show how megaherbivore population size varied before and after the last extinctions in interior Alaska, we use both a database of radiocarbon-dated bone remains (spanning 25–0 ka) and spores of the obligate dung fungus,Sporormiella,recovered from radiocarbon-dated lake-sediment cores (spanning 17–0 ka). Bone fossils show that the last stage of LQEs in the region occurred at about 13 ka ago, but the number of megaherbivore bones remains high into the Holocene.Sporormiellaabundance also remains high into the Holocene and does not decrease with major vegetation changes recorded by arboreal pollen percentages. At two sites, the interpretation ofSporormiellawas enhanced by additional dung fungal spore types (e.g.,Sordaria). In contrast to many sites where the last stage of LQEs is marked by a sharp decline inSporormiellaabundance, in interior Alaska our results indicate the continuance of megaherbivore abundance, albeit with a major taxonomic turnover (includingMammuthusandEquusextinction) from predominantly grazing to browsing dietary guilds. This new and robust evidence implies that regional LQEs were not systematically associated with crashes of overall megaherbivore abundance.

Aim: Biomes can diverge substantially in plant functional traits and disturbance regimens among regions. Given that Neotropical and Afrotropical regions have contrasting histories of the megafauna (because of the Holocene megafaunal extinction in the Neotropics), we hypothesize that they should harbour plants with different traits in relationship to herbivory and fire, especially in savannas. We predicted that herbivory resistance traits should be more prominent in Afrotropical savanna plants and fire resistance in Neotropical savanna plants. Location: Tropics. Time period: Not applicable. Major taxa studied: Angiosperms (woody). Methods: We compiled data for five key plant functional traits (wood density, specific leaf area, maximum tree height, spinescence and proportion of geoxyles) for forest and savanna woody species from the two distant regions (Afrotropics and Neotropics). We related these data to climate, soil and fire variables and tested predictions for megafauna selection. Results: Spines and high wood density were more common among Afrotropical than Neotropical savanna species and species from the two forests. Moreover, the Neotropical savanna region contained more geoxyles than the Afrotropical savanna region. Finally, Afrotropical species were taller than Neotropical species. These differences were consistent with our predictions for trait selection by the megafauna, and these patterns did not change when considering climate, soil and fire regimens in the models. Main conclusions: Our results highlight the great potential of these traits for summarizing disturbance strategy axes in tropical woody species and suggest that global variation in plant traits is unlikely to be understood fully without consideration of historical factors, especially the direct and indirect impacts of megafauna., Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. Grant Number: 88887.311538/2018‐00

Theory predicts that trophic specialization (i.e. low dietary diversity) should make consumer populations sensitive to environmental disturbances. Yet diagnosing specialization is complicated both by the difficulty of precisely quantifying diet composition and by definitional ambiguity: what makes a diet 'diverse'? We sought to characterize the relationship between taxonomic dietary diversity (TDD) and phylogenetic dietary diversity (PDD) in a species-rich community of large mammalian herbivores in a semi-arid East African savanna. We hypothesized that TDD and PDD would be positively correlated within and among species, because taxonomically diverse diets are likely to include plants from many lineages. By using DNA metabarcoding to analyse 1,281 faecal samples collected across multiple seasons, we compiled high-resolution diet profiles for 25 sympatric large-herbivore species. For each of these populations, we calculated TDD and PDD with reference to a DNA reference library for local plants. Contrary to our hypothesis, measures of TDD and PDD were either uncorrelated or negatively correlated with each other. Thus, these metrics reflect distinct dimensions of dietary specialization both within and among species. In general, grazers and ruminants exhibited greater TDD, but lower PDD, than did browsers and non-ruminants. We found significant seasonal variation in TDD and/or PDD for all but four species (Grevy's zebra, buffalo, elephant, Grant's gazelle); however, the relationship between TDD and PDD was consistent across seasons for all but one of the 12 best-sampled species (plains zebra). Our results show that taxonomic generalists can be phylogenetic specialists, and vice versa. These two dimensions of dietary diversity suggest contrasting implications for efforts to predict how consumers will respond to climate change and other environmental perturbations. For example, populations with low TDD may be sensitive to phylogenetically 'random' losses of food species, whereas populations with low PDD may be comparatively more sensitive to environmental changes that disadvantage entire plant lineages-and populations with low dietary diversity in both taxonomic and phylogenetic dimensions may be most vulnerable of all.

The catastrophic loss of large‐bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope analysis of bone collagen in fossil jaws and body size through measurement of fossil teeth; the abundance of material allows us to examine population level responses at millennial scale for the past 16 ka. Sigmodon was not present at the cave during the full glacial, first appearing at ~16 ka after ice sheets were in retreat. It remained relatively rare until ~12 ka when warming temperatures allowed it to expand its species range northward. We find variation in both diet and body size of Sigmodon hispidus over time: the average body size of the population varied by ~20% (90–110 g) and mean δ¹³C and δ¹⁵N values ranged between −13.5 to −16.5‰ and 5.5 to 7.4‰ respectively. A state–space model suggested changes in mass were influenced by diet, maximum temperature and community structure, while the modest changes in diet were most influenced by community structure. Sigmodon maintained a fairly similar dietary niche over time despite contemporaneous changes in climate and herbivore community composition that followed the megafauna extinction. Broadly, our results suggest that small mammals may be as sensitive to shifts in local biotic interactions within their ecosystem as they are to changes in climate and large‐scale biodiversity loss.

Despite at least 20,000 years of coexistence – and the ubiquity of bone technology across the Australian continent – direct evidence for the use of megafaunal materials (skin, bone, teeth, etc.) remains as elusive as evidence for these creatures having been hunted. Amongst the slim evidence for human–megafauna interaction currently available, one of the most often cited cases is the “engraved” incisor from the giant wombat-like Diprotodon optatum recovered from Spring Creek located in Eastern Maar country in south-eastern Australia. Despite comments in the literature that the marks observed on this tooth are unlikely to have been made by lithic tools (as originally proposed), this item has never been re-analysed in order to resolve the question: Which actor made these marks? Here, the results of a new analysis of this specimen are presented. Through microscopic examination of each mark alongside zooarchaeological and ecological data, it is demonstrated that the incisions were indeed not made by human hands, but instead by a small (2–5 kg) mammal, most likely a scavenging spotted-tailed quoll (Dasyurus maculatus).

Supporting information: Figure S1. A three‐dimensional model of the bathymetry in Tristan da Cunha EEZ highlighting the seamounts. Figure S2. Plot of the raw tracking data of all 10 species considered in our analysis of marine hotspots within the Tristan da Cunha EEZ (indicated by the solid black line). Table S1. Plot of the raw tracking data of all 10 species considered in our analysis of marine hotspots within the Tristan da Cunha EEZ (indicated by the solid black line). Table S2. Phenology of the seabird species breeding in the Territory of Tristan da Cunha. Tristan Table S3. Proportion of the time‐at‐sea spent by different species inside and outside the Tristan EEZ based on tracking data of pelagic megafauna activity in the Tristan da Cunha Exclusive Economic Zone. Figure S3. The tracks of three Blue Shark (Prionace glauca) tagged during the National Geographic’s Pristine Seas expedition to Tristan da Cunha (January to February 2017), using MiniPAT tags (Wildlife Computers).