Large Mammal Communities Research Articles

The Deepwater Horizon oil spill marine mammal injury assessment

ESR Endangered Species Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials ESR 33:95-106 (2017) - DOI: https://doi.org/10.3354/esr00808 REVIEW The Deepwater Horizon oil spill marine mammal injury assessment Ryan Takeshita1, Laurie Sullivan2,*, Cynthia Smith3, Tracy Collier4, Ailsa Hall5, Tom Brosnan6, Teri Rowles7, Lori Schwacke8 1Abt Associates Inc., Boulder, CO 80302, USA 2National Oceanic and Atmospheric Administration, Assessment and Restoration Division, Office of Response and Restoration, Santa Rosa, CA 95404, USA 3National Marine Mammal Foundation, San Diego, CA 92106, USA 4Joint Office for Science Support, University Corporation for Atmospheric Research, Boulder, CO 80301, USA 5Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews, UK 6National Oceanic and Atmospheric Administration, Assessment and Restoration Division, Office of Response and Restoration, Silver Spring, MD 20910, USA 7National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Office of Protected Resources, Silver Spring, MD 20910, USA 8National Oceanic and Atmospheric Administration, National Centers for Coastal Ocean Science, Charleston, SC 29412, USA *Corresponding author: laurie.sullivan@noaa.gov ABSTRACT: From 2010 to 2015, a team of scientists studied how the BP Deepwater Horizon (DWH) oil spill affected marine mammals inhabiting the northern Gulf of Mexico, as part of the DWH Natural Resource Damage Assessment process. The scientists conducted the assessment on behalf of the DWH co-Trustees, with the purpose of investigating whether marine mammals were exposed to DWH oil and what types of injuries they suffered as a result of the DWH oil exposure, and then quantifying those injuries to determine the appropriate amount of restoration required to offset the injuries. Photographs, aerial surveys, spatial analyses of the co-occurrence between surface slick and cetacean populations, and chemical fingerprinting of oiled and stranded carcasses all confirm that at least 15 cetacean species were exposed to the DWH surface slick. Cetaceans that encountered the slick likely inhaled, aspirated, ingested, and/or adsorbed oil. In this Theme Section, marine mammal biologists, statisticians, veterinarians, toxicologists, and epidemiologists describe and quantify the adverse effects of this oil exposure. Taken together, this combination of oil spill dynamics, veterinary assessments, pathological, spatial, and temporal analyses of stranded animals, stock identification techniques, population dynamics, and a broad set of coordinated modeling efforts is an unprecedented assessment of how a major oil spill impacted a large and complex marine mammal community and their connected habitats. KEY WORDS: Deepwater Horizon · Marine mammals · Oil · Petroleum · Natural Resource Damage Assessment · Exposure · Injury assessment Full text in pdf format PreviousNextCite this article as: Takeshita R, Sullivan L, Smith C, Collier T and others (2017) The Deepwater Horizon oil spill marine mammal injury assessment. Endang Species Res 33:95-106. https://doi.org/10.3354/esr00808 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in ESR Vol. 33. Online publication date: January 31, 2017 Print ISSN: 1863-5407; Online ISSN: 1613-4796 Copyright © 2017 Inter-Research.

Reconstructing palaeoenvironmental conditions faced by Mousterian hunters during MIS 5 to 3 in southwestern France: A multi-scale approach using data from large and small mammal communities

Evaluating the impact of climate change on Neanderthal groups is frequently hindered by the lack of adequate palaeoenvironmental data. Here, we explore how data concerning large and small mammal communities can be used to reconstruct environmental conditions confronted by Mousterian hunters during MIS 5 to 3 in southwestern France. Ungulate and rodent faunas are analysed using a GIS database integrating 212 faunal assemblages from 44 archaeological and paleontological sequences, revealing considerable geographical and chronological variability in terms of composition. Faunal proxies (small and large mammals) from different types of accumulations (archaeological assemblages, hyena dens and natural traps) are then compared with other independent environmental proxies (marine core, stalagmites). Our results highlight how proxies can differ, notably by reconstructing environmental conditions at distinct geographical scales (local, sub-regional, regional), and how their cross-scale comparison can aid environmental reconstructions of terrestrial ecosystems. The complex response of faunal communities to climate changes suggest that environmental reconstructions at local and sub-regional scales are required before discussing the influence of the environment on Neanderthal behavioural and cultural evolution.

Large mammal community composition and relative abundance under a disturbance gradient in Northeast Costa Rica

Large mammal communities, integral components of Neotropical ecosystems, are increasingly threatened by habitat fragmentation and degradation due to anthropogenic pressures and climate change. Lowland Neotropical palm forests harbor diverse mammal communities, including threatened and endangered species. We monitored three transects in the Barra del Colorado Wildlife Refuge in Northeast Costa Rica from February 2014 until April 2015 documenting large terrestrial mammal and primate detections. Following established large mammal survey methodology, each transect was walked weekly alternating between early morning and late afternoon to maximize detection. The three transects represent three levels of anthropogenic disturbance with highest disturbance at the Cerro, followed by Caño Palma Biological Station (CPBS), and lowest levels in Tortuguero National Park (TNP). Overall we found higher diversity and increased presence of endangered species in TNP and the lowest diversity and lower presence of those species in the Cerro. Overall we detected 25 species; 19 at the Cerro, 22 in TNP and 23 at CPBS. TNP had the highest diversity as calculated by Simpson index (28.3) followed by CBPS (27.9), and the Cerro had the lowest diversity of mammals (2.27). The most influential species driving the differences of communities between the three transects included the white-lipped and collared peccaries, which were both present in higher densities in transects with lower disturbance and higher levels of protection, and domestic dogs which were present in higher densities at the Cerro. This study has documented baseline densities of large mammal communities in the wildlife refuge which can be used as preliminary data for future comparisons. As development is continuing in the region, including construction of a tourist trail at the Cerro, a continued monitoring is recommended to understand the effect of development on mammal communities.

Grain-dependent responses of mammalian diversity to land use and the implications for conservation set-aside.

Diversity responses to land-use change are poorly understood at local scales, hindering our ability to make forecasts and management recommendations at scales which are of practical relevance. A key barrier in this has been the underappreciation of grain-dependent diversity responses and the role that β-diversity (variation in community composition across space) plays in this. Decisions about the most effective spatial arrangement of conservation set-aside, for example high conservation value areas, have also neglected β-diversity, despite its role in determining the complementarity of sites. We examined local-scale mammalian species richness and β-diversity across old-growth forest, logged forest, and oil palm plantations in Borneo, using intensive camera- and live-trapping. For the first time, we were able to investigate diversity responses, as well as β-diversity, at multiple spatial grains, and across the whole terrestrial mammal community (large and small mammals); β-diversity was quantified by comparing observed β-diversity with that obtained under a null model, in order to control for sampling effects, and we refer to this as the β-diversity signal. Community responses to land use were grain dependent, with large mammals showing reduced richness in logged forest compared to old-growth forest at the grain of individual sampling points, but no change at the overall land-use level. Responses varied with species group, however, with small mammals increasing in richness at all grains in logged forest compared to old-growth forest. Both species groups were significantly depauperate in oil palm. Large mammal communities in old-growth forest became more heterogeneous at coarser spatial grains and small mammal communities became more homogeneous, while this pattern was reversed in logged forest. Both groups, however, showed a significant β-diversity signal at the finest grain in logged forest, likely due to logging-induced environmental heterogeneity. The β-diversity signal in oil palm was weak, but heterogeneity at the coarsest spatial grain was still evident, likely due to variation in landscape forest cover. Our findings suggest that the most effective spatial arrangement of set-aside will involve trade-offs between conserving large and small mammals. Greater consideration in the conservation and management of tropical landscapes needs to be given to β-diversity at a range of spatial grains.

On the ecological context of the earliest human settlements in Europe: Resource availability and competition intensity in the carnivore guild of Barranco León-D and Fuente Nueva-3 (Orce, Baza Basin, SE Spain)

With an age of ∼1.4 Ma, the Early Pleistocene archaeopaleontological sites of Barranco León and Fuente Nueva-3 (Orce, Baza Basin, SE Spain) provide the oldest evidence on human presence in Western Europe, including the finding of a deciduous tooth of Homo sp., huge lithic assemblages of Oldowan tradition and abundant cut-marks on large mammal bones. Here we use a mathematical approach based on Leslie matrices to quantify for the large mammal species preserved at the sites the biomass of primary consumers available, the distribution of meat resources among the secondary consumers and the competition intensity within the carnivore guild. The results obtained show a community of large mammals with a high diversity of secondary consumers that would satisfy slightly less than half of their dietary requirements under optimal ecological conditions. In the case of Homo sp., and considering that flesh resources were obtained through the scavenging of ungulate carcasses, the model indicates that the ecosystems of the basin could hold 10–14 individuals per 100 km2 during a year, a value that is close to the mean population density of recent hunter-gatherers. These density estimates decrease slightly when a mixed hunting-scavenging strategy is considered and even more in the case of a strict hunting behavior. In addition, the value of the species competition index obtained for Homo sp. is among the lowest of the carnivore guild. These results suggest that the hominin populations that inhabited Southeast Spain during the Early Pleistocene behaved more as opportunistic scavengers than as active predators.

Using large mammal communities to examine ecological and taxonomic structure and predict vegetation in extant and extinct assemblages

Evolutionary paleoecology is the study of paleoecological patterns of organization over time. However, identification of such patterns within modern communities must be made before any study over time can be attempted. This research analyzes mammalian ecological diversity of 31 African localities classified into eight vegetation types: forests, closed woodlands, closed woodland/bushland transition, bushlands, open woodlands, shrublands, grasslands, and deserts. Ecological diversity is measured as the relative proportions of large mammal trophic and locomotor behaviors within communities. Trophic and locomotor adaptations are assigned on the basis of published observations and stomach contents of 184 African mammal species. Communities are accordingly described on the basis of total percentages of mammalian trophic and locomotor adaptations. Since many paleoecology studies have been made using taxonomic uniformitarianism, this study also examines taxonomic community structure to compare with ecologically derived patterns. Results indicate that particular types of vegetation have predictable percentages of arboreal, aquatic, frugivorous, grazing, etc. large mammals. Therefore, these adaptations, because they are predictable in extant assemblages, can be used to predict paleovegetation as well as to portray the community structure of fossil assemblages. Taxonomic groupings also can be used to predict vegetation in extant assemblages, and taxonomic patterns in communities are compared with ecological ones. The mammalian communities of the Pliocene fossil locality Makapansgat, South Africa, are interpreted using these ecological and taxonomic methodologies. Trophic and locomotor adaptations are assigned for Makapansgat fossil mammals through morphological examination of each taxon. Vegetation type is predicted for these fossil localities, but ecological and taxonomic differences in the assemblages differ from extant communities.

Ungulate distributions in a rangeland with competitors, predators and pastoralists

Summary African rangelands support diverse ungulate communities whose member species exhibit unique combinations of body morphology and behaviour that have evolved over millions of years to limit the effects of competition and predation on fitness, and more recently, to cope with people and livestock. The mechanisms by which native ungulates cope with the combined effects of competition, predation and human disturbance are poorly understood. Addressing this knowledge gap will help guide management and conservation plans for large mammal communities outside of strictly protected areas. We conducted animal counts on line transects and used a spatially explicit distance sampling model to test the influence of bottom–up effects (vegetation), top–down effects from African lion Panthera leo and spotted hyena Crocuta crocuta and human disturbance (livestock density, occupied human settlements) on native ungulate densities and distributions across a multiple‐use rangeland in Kenya. We examined five species that varied in body morphology and foraging strategy, including two large‐bodied grazers (zebra Equus quagga; wildebeest Connochaetes taurinus), two medium‐bodied, mixed‐feeders (Grant's gazelle Nanger granti; impala Aepyceros melampus) and one very large‐bodied browser (giraffe Giraffa camelopardalis tippelskirchi). Densities and distributions of all species varied across available land‐use types, with bottom–up effects (vegetation) and human disturbance having the strongest overall effects. Responses varied by ungulate foraging strategy. Distributions of grazers and the browser (giraffe) changed seasonally, while distributions of mixed‐feeders and a grazer (zebra) changed diurnally. At broad spatial scales, ungulates did not respond to long‐term variation in predation risk though they have been shown to respond behaviourally to short‐term variation in risk. Synthesis and applications. Our results revealed that native ungulates in this multiple‐use rangeland occur at densities comparable to many flagship protected area populations. We attribute observed densities to spatial heterogeneity across this landscape that included variation in human land use (community conservation area, seasonal settlements and livestock grazing, permanent settlements) and vegetation (grassland, bushland, woodland) that changed through time (seasonally, diurnally). This variation allowed ungulates to carve out ecological niches while reducing exposure to the potential limiting effects of competition and human disturbance. For some species, securing access to forage resources and avoiding human disturbance may be associated with costs through increased risk of predation. Our research reveals the trade‐offs native ungulates make to cope with changes in forage availability, human disturbance and predation risk, providing important insights to help guide native ungulate conservation efforts in multiple‐use rangelands.

The Epivillafranchian and the arrival of pigs into Europe

Suids are found in Europe before and during the Olduvai magnetostratigraphic subchron, including the Fonelas P-1 site in the Guadix Basin (Andalusia, Southern Spain, ∼2.0 Ma), in which the remains have been ascribed to Potamochoerus magnus, and many other localities that record the presence of Sus strozzii (e.g., Saint Vallier and Senèze in France). However, there is no pig record in the biochronological range comprised between the post Tasso Faunal Unit, which marks the base of the Late Villafranchian (∼1.8 Ma), and their arrival in Western Europe at layer TE9 from Sima del Elefante, Atapuerca, Northern Spain (∼1.2 Ma), where pigs are recorded under the name of Sus sp., and at the sites of Untermassfeld (Germany), Vallonnet (France) and layer EVT12 of Vallparadís Estació (Spain), dated 1.1–1.0 Ma (MIS31), which suid remains have been ascribed to Sus scrofa priscus in the first site and to Sus sp. in the other two. Later, the genus Sus is recorded everywhere in Europe as a ubiquitous member of the Epivillafranchian/Galerian and posterior faunas. When pigs are in an ecosystem, they use to be abundant in the large mammal community given their opportunistic feeding behavior and high reproductive success. Their short gestation periods and elevated offspring numbers allow them to colonize new and varied environments and territories faster than other ungulates, which use to display a K-reproductive strategy, with a single pup per birth. For this reason, suids are usually preserved in the fossil assemblages after their dispersal and colonization of a geographic region. The arrival of suids phylogenetically related to Sus gr. scrofa into Europe marks the end of the Late Villafranchian and the beginning of the Epivillafranchian, which is approximately dated at ∼1.2 Ma. Given that suids are omnivorous, generalist mammals with bunodont teeth that do not tolerate very low temperatures, this suggests that their colonization of Europe can be related to a change in the ecosystems and climate. In addition, the arrival of suids postdates the earliest arrival of hominins into Western Europe, which is documented at the Orce sites of Barranco León-D and Fuente Nueva-3 (∼1.5–1.2 Ma). In these sites, rich faunal assemblages, abundant lithic artifacts and one human tooth have been unearthed after more than twenty years of excavations, but no evidence of pigs has yet been detected.

Do Collared Peccaries Negatively Impact Understory Insectivorous Rain Forest Birds Indirectly Via Lianas and Vines?

AbstractTropical rain forest understory insectivorous birds are declining, even in large forest reserves, yet the mechanisms remain unclear. Abundant large mammals can reshape forest structure, which degrades foraging microhabitat. We used six sites in Nicaragua, Costa Rica, and Panama with varying collared peccary (Pecari tajacu) density to test three linked hypotheses: (1) locally declining understory insectivores forage preferentially in liana tangles; (2) vine and liana density, cover, and frequency of dense tangles are lower in the presence of abundant collared peccaries; and consequently (3) abundant collared peccaries are associated with reduced understory insectivorous bird abundance. Three insectivores that declined at La Selva preferentially foraged in liana tangles: Checker‐throated Antwren (Epinecrophylla fulviventris), Dot‐winged Antwren (Microrhopias quixensis), and Ruddy‐tailed Flycatcher (Terenotriccus erythrurus). Vine density, liana cover, liana tangle frequency, and forest cover were lower in the presence of collared peccaries relative to experimental mammal exclosures, with the greatest differences at La Selva Biological Station, Costa Rica. Across sites, five of seven vine and liana measures showed negative, curvilinear relationships with peccary densities. Vine and liana measures peaked at sites with intermediate peccary density, and were low at La Selva. Structural equation models suggest negative indirect effects of the collared peccaries on focal bird densities, mediated by vine and liana density, cover, or tangle frequency. Forest area and rainfall affected both lianas and birds, but collared peccaries also contributed to the reduced abundance of understory insectivores. Indirect effects such as that suggested here may occur even in large, protected forest reserves where large mammal communities are changing.

Integrating wildlife conservation with conflicting economic land-use goals in a West African biodiversity hotspot

Half of what remains of the ‘Guinean Forests of West Africa hotspot’ is located in Liberia. However, only about 2% of the country is officially protected. We systematically identified and evaluated priority areas for the protection of large mammals and biodiversity in Liberia under different conservation scenarios. We also assessed current proposed protected areas (PPAs) in terms of achieving pre-determined conservation targets, and determined potential wildlife and biodiversity loss within logging and mining concessions. We systematically collected nationwide data on chimpanzee (Pan troglodytes verus) abundance, large mammal and tree taxonomic diversity, and human threats. We related these to environmental and human impact variables to develop nationwide spatial prediction models that also served as base-layers for spatial prioritization using MARXAN. We improved upon standard software output to evaluate spatial properties of selected sites, determine site-specific target contributions, and estimate potential wildlife and biodiversity loss within logging and mining concessions. The optimal conservation area network contained a candidate list of 92 areas that maximized biodiversity and chimpanzee abundance, minimized threats, and accomplished the preservation of 30% of Liberia's forests. It included more than half of West Africa's second largest chimpanzee population, which spatially coincided with that of some of the most diverse large mammal and tree communities. Logging and mining concessions largely overlapped with existing PPAs and conservation priority areas established in this study, and considerably increased their fragmentation. Existing PPAs, however, only partially covered our areas of prioritization and proved insufficient in meeting conservation targets. We emphasize the need for finding a balance between development and biodiversity conservation, such as through aggregate biodiversity offsets, the use of which is currently being discussed by local government, international investors, and conservation NGOs.

Spatiotemporal hierarchical modelling of species richness and occupancy using camera trap data

Summary Over the last two decades, a large number of camera trap surveys have been carried out around the world and camera traps have been proposed as an ideal tool for inventorying and monitoring medium to large‐sized terrestrial vertebrates. However, few studies have analysed camera trap data at the community level. We developed a multi‐session multi‐species occupancy model that allows us to obtain estimates for species richness and occupancy combining data from multiple camera trap surveys (sessions). By estimating species presence at the session‐level and modelling detection probability and occupancy for each species and sessions as nested random effects, we could improve parameter estimates for each session, especially for species with sparse data. We developed two variants of our model: one was a binary latent states model while the other used a Royle–Nichols formulation for the relationship between detection probability and abundance. We applied both models to data from eight camera trap surveys from south‐eastern Peru including six study sites, 263 camera stations and 17 423 camera days. Sites covered protected areas, a logging concession and Brazil nut concessions. We included habitat (terra firme vs. floodplain) as a covariate for occupancy and trail vs. off‐trail as a covariate for detection. Among‐camera heterogeneity was a serious problem for our data and the Royle–Nichols variant of our model had a much better fit than the binary‐state variant. Both models resulted in similar species richness estimates showing that most of the sites contained intact large mammal communities. Detection probabilities and occupancy values were more variable across species than across sessions within species. Three species showed a habitat preference and four species showed preference or avoidance of trails. Synthesis and applications. Our multi‐session multi‐species occupancy model provides improved estimates for species richness and occupancy for a large data set. Our model is ideally suited for integrating large numbers of camera trap data sets to investigate regional and/or temporal patterns in the distribution and composition of mammal communities in relation to natural or anthropogenic factors or to monitor mammal communities over time.

Stable isotopes in yellow-bellied marmot (Marmota flaviventris) fossils reveal environmental stability in the late Quaternary of the Colorado Rocky Mountains

High elevation plant and animal communities are considered extremely sensitive to environmental change. We investigated an exceptional fossil record of yellow-bellied marmot (Marmota flaviventris) specimens that was recovered from Cement Creek Cave (elev. 2860m) and ranged in age from radiocarbon background circa 49.8calkaBP to ~1calkaBP. We coupled isotopic and radiocarbon measurements (δ18O, δD, δ15N, δ13C, and 14C) of bone collagen from individually-AMS dated specimens of marmots to assess ecological responses by this species to environmental change over time in a high elevation basin in the Rocky Mountains of southwestern Colorado, USA. We find little change in all four isotope ratios over time, demonstrating considerable environmental stability during periods when the marmots were present. The stable ecology and the apparent persistence of the small mammal community in the cave fauna throughout the late Quaternary are in marked contrast to the changes that occurred in the large mammal community, including local extirpation and extinction, at the end of the Pleistocene.

Loss of animal seed dispersal increases extinction risk in a tropical tree species due to pervasive negative density dependence across life stages.

Overhunting in tropical forests reduces populations of vertebrate seed dispersers. If reduced seed dispersal has a negative impact on tree population viability, overhunting could lead to altered forest structure and dynamics, including decreased biodiversity. However, empirical data showing decreased animal-dispersed tree abundance in overhunted forests contradict demographic models which predict minimal sensitivity of tree population growth rate to early life stages. One resolution to this discrepancy is that seed dispersal determines spatial aggregation, which could have demographic consequences for all life stages. We tested the impact of dispersal loss on population viability of a tropical tree species, Miliusa horsfieldii, currently dispersed by an intact community of large mammals in a Thai forest. We evaluated the effect of spatial aggregation for all tree life stages, from seeds to adult trees, and constructed simulation models to compare population viability with and without animal-mediated seed dispersal. In simulated populations, disperser loss increased spatial aggregation by fourfold, leading to increased negative density dependence across the life cycle and a 10-fold increase in the probability of extinction. Given that the majority of tree species in tropical forests are animal-dispersed, overhunting will potentially result in forests that are fundamentally different from those existing now.

The impact of 850,000 years of climate changes on the structure and dynamics of mammal food webs.

Most evidence of climate change impacts on food webs comes from modern studies and little is known about how ancient food webs have responded to climate changes in the past. Here, we integrate fossil evidence from 71 fossil sites, body-size relationships and actualism to reconstruct food webs for six large mammal communities that inhabited the Iberian Peninsula at different times during the Quaternary. We quantify the long-term dynamics of these food webs and study how their structure changed across the Quaternary, a period for which fossil data and climate changes are well known. Extinction, immigration and turnover rates were correlated with climate changes in the last 850 kyr. Yet, we find differences in the dynamics and structural properties of Pleistocene versus Holocene mammal communities that are not associated with glacial-interglacial cycles. Although all Quaternary mammal food webs were highly nested and robust to secondary extinctions, general food web properties changed in the Holocene. These results highlight the ability of communities to re-organize with the arrival of phylogenetically similar species without major structural changes, and the impact of climate change and super-generalist species (humans) on Iberian Holocene mammal communities.

Medium and large-sized mammals of the Reserva Ecológica de Guapiaçú, Cachoeiras de Macacu, RJ

Medium and large-sized terrestrial mammals develop important functions in ecosystems maintenance. However, this group is the most vulnerable to local extinctions, through habitat loss or hunting. This study inventoried the community of medium and large mammals in the Reserva Ecológica de Guapiaçú (REGUA), Cachoeiras de Macacu, RJ, providing data on species composition, richness and abundance. Species were registered through the use of camera traps, sign survey and visual encounters on pre-existing trails and roads. The study was conducted from January to October 2012, with each month considered as a sample unit. An effort of 1568 cameras-day and 120 km traveled, resulted on 302 records of 22 species of medium and large-sized mammals, belonging to eight orders. This value corresponds to more than three-quarters of the richness described from this group in the Atlantic Forest of Rio de Janeiro state. Five species are under some level of regional, national or global threat. Three game species, Pecari tajacu, Cuniculus paca and Dasyprocta leporina were abundant in the area. The observed richness was comparable to that found in other studies conducted in rain forests. Thus, for its high number of species, including those under some degree of threat, we conclude that REGUA is an important area to mammal conservation, especially in the Atlantic Forest of Rio de Janeiro state.

The Evolution of Large Mammal Communities: Beyond Biochronology

Evolution is commonly studied at different levels, from genes to species. It has been questioned whether all these levels are actually real, although it now seems accepted by most scientific investigators that more than one level is actually targeted by selection. Intriguingly, despite the importance of biological interaction is relevant to the course of evolution (and to the level to which selection applies) the obvious locus for biological interaction, the community, has received little evolutionary attention by mammal paleontologists. Herein, we investigate the concept of a biochron, which is the approximation closest to a real community in the paleontological world, and its applications. Then, we offer some clues as to how to use biochrons for investigating community evolution, and explain why paleontological community evolution is a partly novel, highly promising field of research within the realm of paleobiology.

Spatial and ecometric analyses of the Plio‐Pleistocene large mammal communities of the Italian peninsula

AbstractAimKnowledge of mammal community composition across large areas is critical to the reconstruction of biogeographical trends in past ecosystems where mammalian fossils serve as palaeoecological proxies. We employed ‘ecometrics’ (taxon‐free trait analysis) to compare fossil communities of the Italian Plio‐Pleistocene across space and time. We tested the hypotheses that ecometric traits characterizing fossil mammal communities differ between time bins, and that they exhibit geographical correlations.LocationPeninsular Italy, excluding islands (Sardinia and Sicily).MethodsWe explored selected ecometric traits (body weight, biomass, hypsodonty and brachial index) in 69 local fossil assemblages at the scale of nine palaeocommunities (PCOMs), and at the broader scale of ‘mammal age’, or biochronological unit, to which they belong: Villafranchian, Galerian or Aurelian. Principal components analysis, MANOVA and linear discriminant analysis were used to describe differences in the PCOM and mammal age ecospaces. We also tested for the effects of latitude and longitude on the ecometric variables and mapped their distributions during individual mammal ages.ResultsSpatial analysis suggested that neither latitude nor longitude relate meaningfully to any of the ecological parameters under consideration. However, PCOMs in each biochronological interval were successfully discriminated using ecometric traits, with the exception of the localities from Triversa and Pirro, which bore more resemblance to the younger Aurelian localities. The mammal ages were more clearly distinct.Main conclusionsCommunities differ from one another particularly in relation to both the average body weight of herbivores and the entire mammalian fauna and the biomass of prey species. This is probably related to a climatic cooling trend that occurred between the Pliocene and Pleistocene and resulted in the evolution of larger forms. Hypsodonty trends are identified and we support hypsodonty as a valuable ecometric trait, but only at larger temporal scales.

Hunting practices targeting large mammal communities in the Paris Basin in the Upper Palaeolithic

This paper aims to explore the evolutionary role of Upper Palaeolithic hunter–gatherers through their interactions with large mammal communities. Recent advances in the understanding of hunting practices of during the Late Glacial in the Paris basin show how complex human-large mammal relationships may have been. The modelling of various African savannah ecosystems enables these interactions to be approached for prehistoric periods. This framework provides an opportunity for Pleistocene specialists to get a better understanding of the functioning and the structure of animal communities. Further to this, it is now possible to highlight how the top-down and bottom-up mechanisms of herbivore regulation fit together. Thus, the way prehistoric societies selected and hunted their prey provides significant data on the environmental impact of their predation and on environmental conditions. In order to test this ecological framework, the Upper Pleistocene Paris Basin is likely to be interesting for several reasons. First, the physical parameters of this region are well documented and remain very stable during the Upper Palaeolithic, and this enables a focus on the impact of another crucial factor, climate fluctuations. Second, since several cultural entities have been identified during the Upper Pleistocene in the region, the continuity or discontinuity in prey choices appears crucial from an evolutionary point of view.

New perspectives on middle Pleistocene change in the large mammal faunas of East Africa: Damaliscus hypsodon sp. nov. (Mammalia, Artiodactyla) from Lainyamok, Kenya

The middle Pleistocene fossil mammal assemblage from Lainyamok in the southern Kenya rift has previously been considered the oldest (330–392ka) African mammal community consisting entirely of extant species, with the dominant bovid tentatively attributed to the southern African blesbok (Damaliscus cf. dorcas). We show that the blesbok-like fossils from Lainyamok belong to an extinct species, described here as Damaliscus hypsodon sp. nov. The D. hypsodon hypodigm includes the previously unnamed small alcelaphine material known from late Pleistocene sites elsewhere in Kenya and Tanzania. Its dental anatomy, together with an ecomorphological analysis of its postcrania, indicates that D. hypsodon grazed in open and arid grassland environments. Although Lainyamok is no longer represented entirely by extant species, the absence of species common earlier in the middle Pleistocene of East Africa suggests substantial faunal turnover between 500 and 400ka. Damaliscus hypsodon persisted in East Africa until the end of the Pleistocene and its extinction can be attributed to a loss of arid grassland environments at the onset of the Holocene. The fossil evidence from southern Kenya suggests that the development of the taxonomically modern large mammal community was a long-term process characterized by the extinction of grazing specialists, with marked turnover occurring between ~500 and 400ka and near the end of the Pleistocene.

A Survey of mid and large bodied mammals in Núcleo Caraguatatuba, Serra do Mar State Park, Brazil

We applied complementary survey techniques to obtain a baseline species list of mid and large bodied mammals in Núcleo Caraguatatuba, Serra do Mar State park, Brazil. Between May and September 2011 we surveyed the community of mid and large bodied mammals using diurnal line transect census (212.4 km), camera-traps (223.2 camera-trap days) and track-stations (478 track-station days). A total of 18 species were recorded from 14 families in eight orders. We recorded the presence of seven species considered threatened in the State of São Paulo, including Primates (Brachyteles arachnoides), Artiodactyla (Mazama cf. americana and Tayassu pecari), Carnivora (Leopardus pardalis, Leopardus tigrinus and Puma concolor) and Perissodactyla (Tapirus terrestris). Based on extrapolated (First order jackknife) species richness estimates we predict that there are between 19 and 32 species of mid and large bodied mammals in the Núcleo. Our revised Mammal Priority Index ranked Núcleo Caraguatatuba as being of medium overall importance for the conservation of mid and large bodied mammals in the Atlantic Forest. Combined with the number and diversity of species recorded, our results demonstrate that this Núcleo is an important area for mammal conservation.