Taxon-specific (targeted) sampling, although used in many studies of fossil predator–prey interactions, has been considered to yield less robust predation-related data than bulk sampling. In this ...study, we tested the utility of taxon-specific sampling by comparing drilling predation data from taxon-specific samples collected by novice and veteran collectors with data from bulk samples collected at the same sites. The bivalves Lirophora latilirata, Astarte concentrica, and Cyclocardia granulata were collected by targeted and bulk sampling from the Lower Pleistocene lower Waccamaw Formation at five localities in southeastern North Carolina. Variables studied included shell length and thickness, left-right valve frequency, drillhole site and prey size selectivity, drilling frequency, and prey effectiveness. Of 139 comparisons, 75% yielded no difference between predation metrics from targeted and bulk samples; most significant differences involved size-related variables. When data were size standardized (as is frequently done in predation studies), 97% of 70 tests showed no difference between the two collecting methods. In addition, when samples collected by novice and veteran collectors were compared, 97% of 214 tests showed no significant differences in predation metrics; the only significant differences involved size-related variables. Results were similar for all three species and across localities. Taxon-specific sampling therefore produces reliable quantitative results for studies of drilling predation, especially when data are standardized by specimen size, and may be superior to bulk sampling when rare or large-bodied taxa are studied.
► We examine two sampling methods commonly used in drilling predation studies. ► Taxon-specific and bulk samples of bivalves yielded comparable predation metrics. ► Targeted samples by novice and veteran collector yielded comparable results. ► Results are most robust when predation data are size-standardized. ► Targeted sampling is a valuable method in research on drilling predation.
The late Oligocene/early Miocene to Recent fossil record of whelk predation on species of the venerid bivalve genus
Mercenaria was evaluated to trace the history of specialization in feeding behavior ...within the predatory gastropod subfamily Busyconinae. Today, whelk species either employ a wedging or chipping mode of predation when feeding on their bivalve prey. Whelk chipping predation leaves a characteristic trace on the shell of
Mercenaria. The temporal distribution of successful and failed whelk predation traces on the shell of
Mercenaria suggests two independent origins of chipping behavior within the group. The behavior first evolved in the late Miocene
Busycotypus species complex, but was likely lost evolutionarily due to the extinction of the whelk lineage responsible for the traces at the end of the Miocene. The behavior evolved independently in the
Busycon-Sinistrofulgur clade during the late Pliocene. Circumstances that may have contributed to ecological diversification and specialization in the Busyconinae are complex. The evolution of chipping behavior is associated with times of high productivity and ecological complexity during the late Miocene and Pliocene in the western Atlantic.
Conservation paleobiology aims to apply data from geohistorical records, such as fossils and their associated sediments, to the conservation of biodiversity and ecosystem services. Integrating ...geohistorical data into conservation/restoration practice, however, has proved difficult. To better understand how geohistorical data can be more effectively integrated into the conservation/restoration of an ecologically, economically, and culturally important group—oysters—a web-based survey was conducted to assess the awareness and understanding of geohistorical data and perspectives on their use in restoration among oyster researchers and restoration practitioners in the United States. The 97 survey responses not only demonstrate overall willingness to use geohistorical data in oyster restoration but also highlight knowledge gaps. For instance, although many respondents understood some uses for geohistorical data, e.g., providing baseline information, few respondents mentioned others, such as reconstructing historical ranges of variation of ecosystem attributes. Respondents were also generally not aware of the full range of restoration metrics that can be measured from geohistorical records. The responses further suggested how geohistorical information might both reinforce and expand the information currently available to oyster restoration professionals. For instance, only half of respondents indicated that their baseline information predates the 20ᵗʰ century, but geohistorical records of oysters can provide data on timescales ranging from decades to millennia. Finally, it is argued that to raise awareness of this underutilized information and address respondents' doubts about the completeness, precision/accuracy, and relevance of geohistorical data in a rapidly changing, human-dominated world, increased collaboration between conservation paleobiologists and conservation/restoration scientists is needed.
Where do species that become important players in ecosystems evolve? This simple yet crucial question must be answered if we want to understand how the biosphere is rejuvenated following a crisis. We ...cannot simply assume that the environments in which we find fossil remains of a given species, or living populations of a species, are the environments in which that species evolved. Take the most obvious example: Fossil human skeletons have been unearthed by the hundreds in North America, but all available evidence points to a human origin in Africa. We can often identify the general geographic origins of species and clades thanks to fossil occurrences and the application of phylogenetic techniques; but can we do likewise for more ecological aspects of the environment? Advances in population biology and in paleobiology now permit us to outline a hypothesis of the circumstances most favorable to the evolution of abundant, widespread, or ecologically powerful species, those with adaptations that are selectively advantageous across many environments, and large short-term and long-term effects in ecosystems.
The “Research Experiences for Undergraduates (REU) in Biodiversity Conservation” project models transdisciplinary training in conservation science, and particularly in the emerging field of ...conservation paleobiology (CPB), which applies geohistorical records (e.g., sediments, fossils) and approaches to solve conservation problems. We analyzed recent funding patterns in the National Science Foundation REU program (Biological Sciences and Geosciences directorates) and found that, at most REU sites, undergraduates conduct individual projects supervised by a mentor. In contrast, at the REU in Biodiversity Conservation Site, students from geology, biology, archaeology, and environmental sciences worked in transdisciplinary teams on conservation‐related research using fossil, archaeological, and modern samples. The project successfully incorporated CPB approaches and taught research and soft skills useful in conservation; 85% of students subsequently pursued STEM graduate study or employment. However, because translational science partnerships with conservation practitioners were not sought, the research‐implementation gap remained. We propose a new model for REU sites involving conservation practitioners and stakeholders as partners in research that includes the human dimension and meets community needs, resulting in transdisciplinary, team‐focused training that yields actionable results. We recommend that the National Science Foundation encourage researchers to think beyond typical one‐on‐one mentorship when planning an REU, especially for conservation science projects.
Arms races among invertebrates, intelligence gathering by the immune system and alarm calls by marmots are but a few of nature's security strategies that have been tested and modified over billions ...of years. This provocative book applies lessons from nature to our own toughest security problems--from global terrorism to the rise of infectious disease to natural disasters. Written by a truly multidisciplinary group including paleobiologists, anthropologists, psychologists, ecologists, and national security experts, it considers how models and ideas from evolutionary biology can improve national security strategies ranging from risk assessment, security analysis, and public policy to long-term strategic goals.
AMBI and Bentix are widely used benthic indices for guiding remediation decisions under two major pieces of environmental legislation in Europe — the Water Framework Directive (WFD) and the Marine ...Strategy Framework Directive (MSFD). These indices usually incorporate all marine benthic invertebrates in a sample. Some recent studies, however, have applied these benthic indices to only mollusk species due to the ease of identifying only one taxonomic group to the species level and because death assemblages (accumulated dead mollusk shells in sediments) may be valuable sources of data for assessing baseline conditions. Although they found that ecological status differences can be detected by applying AMBI and Bentix to mollusks, these studies did not test whether mollusk-only index values, and the ecological statuses indicated by them, are equivalent to those calculated from the whole benthic community. To test this assumption, we performed a meta-analysis of data from 12 European benthic community studies comparing mollusk-only index values with whole-community values. Using five mollusk-only data sets, we also assessed whether application of AMBI and Bentix to molluscan death assemblages can be used to detect changes in ecological status over time. We show that the application of AMBI and Bentix to only the molluscan taxa in benthic communities is a viable method for determining the ecological status of water bodies. Our results also suggest that the application of benthic indices to molluscan death assemblages has great potential to 1) establish baseline conditions for assessing ecological status under the WFD and 2) estimate the natural range of variation of ecosystem attributes for defining sustainability thresholds under the MSFD. We outline three recommendations for the future use of mollusk-only AMBI and Bentix based on our results: 1) mollusk-only index values should be adjusted to facilitate comparisons with whole-community studies; 2) local ecological group assignments should be used if possible; and 3) we encourage collaboration between paleoecologists and benthic ecologists to facilitate interpretations of index values from death assemblages. We conclude that mollusk-only benthic index assessments of molluscan death assemblages have the potential to be a powerful tool for guiding management decisions under the WFD and MSFD.
Drillholes made by naticid and muricid gastropods are frequently used in evolutionary and ecological studies because they provide direct, preservable evidence of predation. The muricid Ecphora is ...common in many Neogene Atlantic Coastal Plain assemblages in the United States, but is frequently ignored in studies of naticid predation. We used a combination of Pliocene fossil, modern beach, and experimentally derived samples to evaluate the hypothesis that Ecphora was an important source of drillholes in infaunal bivalve prey shared with naticids. We focused on the large, thick-shelled venerid, Mercenaria, which is commonly drilled by naticids today. Laboratory experiments, modern beach samples, and the published literature confirm that naticids preferentially drill near the umbo (significant clumping of holes), show a significant correlation between prey size and predator size (estimated by outer borehole diameter), and prefer Mercenaria <50 mm antero-posterior width when other prey are present. Fossil samples containing Ecphora (with or without other large muricids) show no drillhole site stereotypy (no significant clumping, greater variability in placement), no significant predator: prey size correlation, drilled prey shells larger than the largest modern naticids could produce in an experimental setting, and drillholes larger in diameter than those estimated for the largest Pliocene naticids, thus supporting our hypothesis. Substantial overlap in the placement of holes drilled by naticids and muricids, however, made identifying predators from drillhole position problematic. The lack of overlapping ranges of prey shell thickness between fossil and other samples precluded the use of drill- hole morphology to establish predator identity (e.g., ratio of inner borehole diameter to outer borehole diameter, drillhole angle). Whereas the difficulty in determining predator identity from drillholes limits the types of analyses that can be reliably performed in mixed-predator assemblages, recognizing Ecphora as a prominent drilling predator creates the opportunity to investigate previously unrecognized questions.
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