Conservation paleobiology: putting the dead to work Dietl, Gregory P.; Flessa, Karl W.
Trends in ecology & evolution (Amsterdam),
2011, 2011-Jan, 2011-01-00, 20110101, Volume:
26, Issue:
1
Journal Article
Peer reviewed
Geohistorical data and analyses are playing an increasingly important role in conservation biology practice and policy. In this review, we discuss examples of how the near-time and deep-time fossil ...record can be used to understand the ecological and evolutionary responses of species to changes in their environment. We show that beyond providing crucial baseline data, the conservation paleobiology perspective helps us to identify which species will be most vulnerable and what kinds of responses will be most common. We stress that inclusion of geohistorical data in our decision-making process provides a more scientifically robust basis for conservation policies than those dependent on short-term observations alone.
Mechanical ventilation is an important tool for supporting critically ill patients but may also exert pathological forces on lung cells leading to Ventilator-Induced Lung Injury (VILI). We ...hypothesised that inhibition of the force-sensitive transient receptor potential vanilloid (TRPV4) ion channel may attenuate the negative effects of mechanical ventilation. Mechanical stretch increased intracellular Ca2+ influx and induced release of pro-inflammatory cytokines in lung epithelial cells that was partially blocked by about 30% with the selective TRPV4 inhibitor GSK2193874, but nearly completely blocked with the pan-calcium channel blocker ruthenium red, suggesting the involvement of more than one calcium channel in the response to mechanical stress. Mechanical stretch also induced the release of pro-inflammatory cytokines from M1 macrophages, but in contrast this was entirely dependent upon TRPV4. In a murine ventilation model, TRPV4 inhibition attenuated both pulmonary barrier permeability increase and pro-inflammatory cytokines release due to high tidal volume ventilation. Taken together, these data suggest TRPV4 inhibitors may have utility as a prophylactic pharmacological treatment to improve the negative pathological stretch-response of lung cells during ventilation and potentially support patients receiving mechanical ventilation.
Humans now play a major role in altering Earth and its biota. Finding ways to ameliorate human impacts on biodiversity and to sustain and restore the ecosystem services on which we depend is a grand ...scientific and societal challenge. Conservation paleobiology is an emerging discipline that uses geohistorical data to meet these challenges by developing and testing models of how biota respond to environmental stressors. Here we (
a
) describe how the discipline has already provided insights about biotic responses to key environmental stressors, (
b
) outline research aimed at disentangling the effects of multiple stressors, (
c
) provide examples of deliverables for managers and policy makers, and (
d
) identify methodological advances in geohistorical analysis that will foster the next major breakthroughs in conservation outcomes. We highlight cases for which exclusive reliance on observations of living biota may lead researchers to erroneous conclusions about the nature and magnitude of biotic change, vulnerability, and resilience.
Making decisions about natural resource conservation is often difficult because of a lack of longer‐term data, which are needed to provide a frame of reference for identifying and choosing ...appropriate responses to threats impacting species, ecosystems, and the benefits they provide to people.
Despite the promise the field of conservation paleobiology holds for using geohistorical data and insights to provide this longer‐term perspective, examples of successful implementation are uncommon.
Over the past decade, many conservation biology researchers and practitioners have turned to knowledge co‐production to overcome this same challenge. Co‐production prioritizes collaboration between academic and non‐academic partners to produce actionable knowledge that better aligns with conservation practitioners' needs and concerns.
We argue that the conservation paleobiology community must similarly build collective competence to engage more effectively in shared “learning spaces” where actionable knowledge is co‐produced. We draw from our experiences with the Historical Oyster Body Size project and lessons learned from other fields to identify key attributes of actionable geohistorical knowledge and the meaningful co‐production processes that produced it.
Familiarity with these concepts will benefit conservation paleobiologists and all researchers who aspire to help develop longer‐lasting, defensible and more equitable solutions to complex conservation problems presented by a changing world.
We draw from our experiences with the Historical Oyster Body Size project and lessons learned from other fields to identify key attributes of actionable geohistorical knowledge and the meaningful co‐production processes that produced it. Familiarity with these concepts will benefit conservation paleobiologists and all researchers who aspire to help develop longer‐lasting and more equitable solutions to complex conservation problems presented by a changing world.
Conservation decision-making is a forward-looking process that involves choices among alternative images of how the future will unfold. Scenarios, easily understood as stories about plausible ...futures, are emerging as a powerful approach used by the conservation community to define a range of socio-ecological futures when standard, predictive modelling approaches to decision-making are inappropriate, providing a framework for making robust decisions under uncertainties. Conservation palaeobiologists can help the conservation community imagine the future. The utility of the past centres on orienting us to the present-grounding the future in the realm of what is plausible-by providing context against which to think about future scenarios, which may help stakeholders and decision-makers to develop a new mental map of a conservation problem, inspiring our intentions and moving us purposefully toward a desirable tomorrow. This article is part of a discussion meeting issue 'The past is a foreign country: how much can the fossil record actually inform conservation?'
Several methods have been developed to standardize frequencies of failed shell-crushing predation preserved as repair scars on the shells of mollusks to account for factors known to influence the ...accumulation of repairs. Our understanding of the potential biases inherent in repair frequency analyses, however, remains incomplete due to a lack of systematic comparison and evaluation of available methods. Here we examine the effects of three different types of data standardization—body size, shape, and exposure time to enemies—on the calculation of repair frequency for a hypothetical data set of 1,000 specimens of a marine gastropod species that varies across its geographic range in morphology and life history. We based assumptions for the ecological parameters (e.g., variation in growth rates and morphology) of our model system on literature reports of living marine gastropod species. We initially structured our unstandardized data set to show equivalent repair frequencies throughout the species' geographic range. Subsequent standardization of this data set by size, shape, and exposure time revealed a progressively stronger spatial pattern, with higher repair frequencies to the south. This finding suggests that the comparison of unstandardized data may be misleading. The continued use and development of standardization methods should both enhance our ability to detect ecologically meaningful signals, and facilitate unbiased tests of hypotheses concerned with the importance of shell-crushing predators in ecology and evolution.
•Mollusc-only M-AMBI outperformed mollusc-only AMBI in assessing ecological quality.•Mollusc-only M-AMBI identified environmental remediation needs with > 90% precision.•Molluscs provide a cost- and ...time-effective means of assessing ecological quality.
AMBI and M-AMBI are widely used biotic indices for assessing the ecological quality status of benthic macroinvertebrate communities in estuarine and coastal soft-bottom habitats. Identifying the species needed for estimating these indices, however, is both expensive and time-consuming, and requires a high degree of taxonomic expertise. The use of proxy taxa as a means of subsampling the target community may save time, resources, and the breadth of taxonomic expertise needed. Our study used macroinvertebrate benthic survey data from the Atlantic Coast of the United States to test the fidelity of molluscs as proxies of the whole community. We calculated the AMBI and M-AMBI scores for both the molluscan and whole communities and then adjusted the molluscan-only index scores to that of the whole community using the linear relationship between the two communities within a Bayesian framework. We found that the mollusc-only AMBI approach underperformed at classifying the ecological quality of the whole community, particularly regarding sample sites classified as needing remediation. The low performance of the mollusc-only AMBI approach is likely due to the dearth of molluscs with high environmental stress tolerances. In contrast, the mollusc-only M-AMBI outperformed AMBI at classifying ecological quality. The M-AMBI linear model correctly classified nearly all of the adjusted mollusc-only sample sites needing remediation. The increased efficacy of mollusc-only M-AMBI may be due to the incorporation of species richness and diversity into the index, as both metrics were highly correlated between the molluscan and whole communities. Mollusc-only M-AMBI did have some drawbacks, however, with fidelity decreasing as ecological quality decreased. Overall, our study highlights the potential utility of a mollusc-only approach for assessing the ecological quality of estuarine and coastal soft-bottom habitats.
Retrospective estimates of life-history traits (e.g., growth rate, lifespan, phenology) of mollusks are valuable data for a number of fields, including paleontology, archaeology, and fisheries ...science. The best option for obtaining these data for species such as oysters that lack reliable morphological indicators of annual accretionary growth (e.g., growth lines) is to use time consuming and expensive stable isotope analyses. However, laser ablation analyses of Mg/Ca are faster and less expensive than stable isotope analyses, and although several studies have shown Mg/Ca ratios in bivalve shells do not reflect water temperature, there is often a weak correlation that may allow annual cycles to be detected. Here, we explore the utility of line scan analyses of Mg/Ca ratios using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) as a more rapid and less expensive method for obtaining ontogenetic age estimates of mollusk shells than more traditional oxygen stable isotope analyses. We tested this method by measuring Mg/Ca ratios from 21 fossil and modern specimens of two oyster species, Crassostrea virginica and Magallana gigas (formerly Crassostrea gigas), collected across a wide geographic area along the coast of the United States. We compared Mg/Ca growth profiles with either known lifespans or with growth characteristics estimated from δ18O profiles. These analyses showed that Mg/Ca profiles from laser ablation analyses reliably reproduced the annual features of the more widely used δ18O profiles. In total, 97% (n=102) of all seasonal peaks and troughs, including both those from the δ18O profiles and the expected patterns in the shells of known age, were detectable in the Mg/Ca profiles. We conclude that laser ablation analysis of Mg/Ca ratios is a rapid and cost effective alternative to stable isotope analysis for retrospective estimation of the growth characteristics of oysters and potentially other taxa with shells lacking reliable annual morphological features.
•Use of LA-ICP-MS line scans of Mg/Ca ratios for oyster sclerochronology was tested.•Oyster lifespan estimates using Mg/Ca and traditional δ18O profiles were similar.•LA-ICP-MS analyses are more rapid and less expensive than δ18O analyses.•Mg/Ca ratios are a viable alternative to δ18O values for oyster sclerochronology.
Predatory naticid gastropods typically attack other infaunal molluscs by drilling holes that record their activities in the shells of their prey. Other modes of naticid predation, which need not ...leave complete boreholes, have been noted in the literature and may complicate interpretation of the record of naticid predation in fossil and modern assemblages. 'Smothering' is an alternative form of predation that has never been defined clearly with respect to naticid gastropods. Feeding occurs in the absence of a completed drillhole; in most cases suffocation is implied, but reported deaths may be linked to an array of mechanisms (e.g. direct feeding, anaesthetizing mucus). We examine the pervasiveness of alternative modes of predation employed by naticids reported in the literature and offer recommendations regarding the terminology used in referring to such mechanisms. Because it is unclear if predatory behaviours such as suffocation are common in natural settings or are mostly artefacts of laboratory conditions such as insufficient substrate, we examined experimentally the influence of different sediment depths on drilling vs suffocation of Mercenaria mercenaria prey by Neverita duplicata. More than 99% (n = 404) of the clams recorded as consumed in our experiments were drilled, regardless of sediment depth, with <1% (n = 3) noted as cases of potential suffocation. Our results indicate that shallower sediment depths do not affect drilling in this species. Analysis of previous studies indicates that prey health and other laboratory effects are likely responsible for many instances of suffocation reported in the literature. Thus concerns regarding use of drillholes as an indicator of predation by naticids in modern and fossil deposits should be alleviated. Future work on other alternative modes of predation by naticids, in both laboratory and field experiments, should focus on validating reported occurrences of such predation and identifying different mechanisms that may be involved.
The fossil record is the only source of information on the long-term dynamics of species assemblages. Here we assess the degree of ecological stability of the epifaunal pterioid bivalve assemblage ...(EPBA), which is part of the Middle Devonian Hamilton fauna of New York--the type example of the pattern of coordinated stasis, in which long intervals of faunal persistence are terminated by turnover events induced by environmental change. Previous studies have used changes in abundance structure within specific biofacies as evidence for a lack of ecological stability of the Hamilton fauna. By comparing data on relative abundance, body size, and predation, indexed as the frequency of unsuccessful shell-crushing attacks, of the EPBA, we show that abundance structure varied through time, but body-size structure and predation pressure remained relatively stable. We suggest that the energetic set-up of the Hamilton fauna's food web was able to accommodate changes in species attributes, such as fluctuating prey abundances. Ecological redundancy in prey resources, adaptive foraging of shell-crushing predators (arising from predator behavioral or adaptive switching in prey selection in response to changing prey abundances), and allometric scaling of predator-prey interactions are discussed as potential stabilizing factors contributing to the persistence of the Hamilton fauna's EPBA. Our study underscores the value and importance of multiple lines of evidence in tests of ecological stability in the fossil record.
PDF
