Despite the promise conservation paleobiology holds for using geohistorical data and insights to ... more Despite the promise conservation paleobiology holds for using geohistorical data and insights to solve conservation problems, training in the field typically does not equip students to be competent environmental problem solvers. The intention of this perspective piece is to start a conversation about how we might train conservation paleobiology students better, focusing on the competencies needed to promote deep engagement with “wicked” conservation problems that are difficult to solve. Ongoing conversations regarding design of academic programs in sustainability, a field allied with conservation science, can inform our discussion. The sustainability literature has defined an interrelated set of “core competencies” that go beyond general academic competencies to enable real-world sustainability problem solving: systems thinking, temporal thinking, normative thinking, strategic thinking, and interpersonal competence. Conservation paleobiology is usually taught within geology programs...
Conservation paleobiology aims to provide a longer-term perspective on environmental problems to ... more Conservation paleobiology aims to provide a longer-term perspective on environmental problems to inform decisions about natural resource conservation. As such, conservation paleobiology research falls short when geohistorical data and insights do not inform conservation practice, contributing to the well-known idea that a “gap” exists between the production and use of science in the environmental realm. Our study quantified the extent of this research-implementation (or knowing-doing) gap through a systematic literature review and survey questionnaire. We determined whether empirical studies in conservation paleobiology with a link to conservation, management, or restoration documented the use of geohistorical data to implement some form of action or if there was a specific mention of how the geohistorical data could be used in theory. Results indicate that “applied” conservation paleobiology has a poor record of translating research into action. Tangible conservation impacts were e...
In the current era of Big Data, existing synthesis tools (e.g. formal meta-analysis) are useful f... more In the current era of Big Data, existing synthesis tools (e.g. formal meta-analysis) are useful for handling the deluge of data and information. However, there is a need for complementary tools that help to (i) structure data and information, (ii) closely connect evidence to theory and (iii) further develop theory. We present the hierarchy-of-hypotheses (HoH) approach to address these issues. In an HoH, hypotheses are conceptually and visually structured in a hierarchically nested way, where the lower branches can be directly connected to empirical results. Used as an evidence-driven, bottom-up approach, it can (i) show connections between empirical results, even when derived through diverse approaches; and (ii) indicate under which circumstances hypotheses are applicable. Used as a theory-driven, top-down method, it helps uncover mechanistic components of hypotheses. We offer guidance on how to build an HoH, provide examples from population and evolutionary biology and propose term...
The effects of overdispersion and zero inflation (e.g., poor model fits) can result in misinterpr... more The effects of overdispersion and zero inflation (e.g., poor model fits) can result in misinterpretation in studies using count data. These effects have not been evaluated in paleoecological studies of predation and are further complicated by preservational bias and time averaging. We develop a hierarchical Bayesian framework to account for uncertainty from overdispersion and zero inflation in estimates of specimen and predation trace counts. We demonstrate its application using published data on drilling predators and their prey in time-averaged death assemblages from the Great Barrier Reef, Australia. Our results indicate that estimates of predation frequencies are underestimated when zero inflation is not considered, and this effect is likely compounded by removal of individuals and predation traces via preservational bias. Time averaging likely reduces zero inflation via accumulation of rare taxa and events; however, it increases the uncertainty in comparisons between assemblage...
Site-selectivity analysis of drilling predation traces may provide useful behavioral information ... more Site-selectivity analysis of drilling predation traces may provide useful behavioral information concerning a predator interacting with its prey. However, traditional approaches exclude some spatial information (i.e., oversimplified trace position) and are dependent on the scale of analysis (e.g., arbitrary grid system used to divide the prey skeleton into sectors). Here we introduce the spatial point pattern analysis of traces (SPPAT), an approach for visualizing and quantifying the distribution of traces on shelled invertebrate prey, which includes improved collection of spatial information inherent to drillhole location (morphometric-based estimation), improved visualization of spatial trends (kernel density and hotspot mapping), and distance-based statistics for hypothesis testing (K-, L-, and pair correlation functions). We illustrate the SPPAT approach through case studies of fossil samples, modern beach-collected samples, and laboratory feeding trials of naticid gastropod pre...
As the climate changes and ecosystems shift toward novel combinations of species, the methods and... more As the climate changes and ecosystems shift toward novel combinations of species, the methods and metrics of conservation science are becoming less species-centric. To meet this growing need, marine conservation paleobiologists stand to benefit from the addition of new, taxon-free benthic indices to the live–dead analysis tool kit. These indices, which were developed to provide actionable, policy-specific data, can be applied to the readily preservable component of benthic communities (e.g., mollusks) to assess the ecological quality status of the entire community. Because these indices are taxon-free, they remain applicable even as the climate changes and novel communities develop—making them a potentially valuable complement to traditionally applied approaches for live–dead analysis, which tend to focus on maintaining specific combinations of species under relatively stable environmental conditions. Integrating geohistorical data with these established indices has potential to inc...
Philosophical Transactions of the Royal Society B: Biological Sciences
Conservation decision-making is a forward-looking process that involves choices among alternative... more 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 f...
Few shell-crushing predators can excavate prey living deep within the sediment. Despite this infa... more Few shell-crushing predators can excavate prey living deep within the sediment. Despite this infaunal refuge from predators, many deep-burrowing bivalves display a strikingly high incidence of shell damage when compared with species living at shallower depths. A non-predatory origin is necessary to explain this high incidence of injury. To evaluate the generality of this hypothesis, repair frequency (number of repairs per shell), along with position and geometry, were determined for 68 Neogene bivalve species from the US Atlantic and Gulf Coastal Plain, seven of which are classified as deep burrowers (>20 cm depth of sediment penetration). Panopea bitruncata, Panopea floridana, Panopea reflexa, and Panopea americana, which are among the deepest burrowers (up to 100 cm), have repair frequencies (2.8– 6.2) that are higher than any other species, while the value for Cyrtopleura costata (0.76) is exceeded only by semi-infaunal Atrina species (1.12). However, not all deep-burrowing sp...
We are among the scientists who have documented the environmental and ecological changes to the U... more We are among the scientists who have documented the environmental and ecological changes to the Upper Gulf of California following the reduction in the Colorado River’s flow. We object to any suggestion that our research supports Manjarrez-Bringas et al.’s conclusion that the decline in the Colorado River’s flow is the reason for the decline in the population of the endangered vaquita porpoise (Phocoena sinus). Manjarrez-Bringas et al.’s conclusions are incongruent with their own data, their logic is untenable, their analyses fail to consider current illegal fishing practices, and their recommendations are unjustified and misdirected. Vaquita face extinction because of bycatch, not because of the lack of river flow.
Conservation of species and ecosystems is increasingly difficult because anthropogenic impacts ar... more Conservation of species and ecosystems is increasingly difficult because anthropogenic impacts are pervasive and accelerating. Under this rapid global change, maximizing conservation success requires a paradigm shift from maintaining ecosystems in idealized past states toward facilitating their adaptive and functional capacities, even as species ebb and flow individually. Developing effective strategies under this new paradigm will require deeper understanding of the long-term dynamics that govern ecosystem persistence and reconciliation of conflicts among approaches to conserving historical versus novel ecosystems. Integrating emerging information from conservation biology, paleobiology, and the Earth sciences is an important step forward on the path to success. Maintaining nature in all its aspects will also entail immediately addressing the overarching threats of growing human population, overconsumption, pollution, and climate change.
Water management that alters riverine ecosystem processes has strongly influenced deltas and the ... more Water management that alters riverine ecosystem processes has strongly influenced deltas and the people who depend on them, but a full accounting of the trade-offs is still emerging. Using palaeoecological data, we document a surprising biogeochemical consequence of water management in the Colorado River basin. Complete allocation and consumptive use of the river's flow has altered the downstream estuarine ecosystem, including the abundance and composition of the mollusc community, an important component in estuarine carbon cycling. In particular, population declines in the endemic Colorado delta clam, Mulinia coloradoensis, from 50--125 individuals m(-2) in the pre-dam era to three individuals m(-2) today, have likely resulted in a reduction, on the order of 5900-15 000 t C yr(-1) (4.1-10.6 mol C m(-2) yr(-1)), in the net carbon emissions associated with molluscs. Although this reduction is large within the estuarine system, it is small in comparison with annual global carbon e...
Despite the promise conservation paleobiology holds for using geohistorical data and insights to ... more Despite the promise conservation paleobiology holds for using geohistorical data and insights to solve conservation problems, training in the field typically does not equip students to be competent environmental problem solvers. The intention of this perspective piece is to start a conversation about how we might train conservation paleobiology students better, focusing on the competencies needed to promote deep engagement with “wicked” conservation problems that are difficult to solve. Ongoing conversations regarding design of academic programs in sustainability, a field allied with conservation science, can inform our discussion. The sustainability literature has defined an interrelated set of “core competencies” that go beyond general academic competencies to enable real-world sustainability problem solving: systems thinking, temporal thinking, normative thinking, strategic thinking, and interpersonal competence. Conservation paleobiology is usually taught within geology programs...
Conservation paleobiology aims to provide a longer-term perspective on environmental problems to ... more Conservation paleobiology aims to provide a longer-term perspective on environmental problems to inform decisions about natural resource conservation. As such, conservation paleobiology research falls short when geohistorical data and insights do not inform conservation practice, contributing to the well-known idea that a “gap” exists between the production and use of science in the environmental realm. Our study quantified the extent of this research-implementation (or knowing-doing) gap through a systematic literature review and survey questionnaire. We determined whether empirical studies in conservation paleobiology with a link to conservation, management, or restoration documented the use of geohistorical data to implement some form of action or if there was a specific mention of how the geohistorical data could be used in theory. Results indicate that “applied” conservation paleobiology has a poor record of translating research into action. Tangible conservation impacts were e...
In the current era of Big Data, existing synthesis tools (e.g. formal meta-analysis) are useful f... more In the current era of Big Data, existing synthesis tools (e.g. formal meta-analysis) are useful for handling the deluge of data and information. However, there is a need for complementary tools that help to (i) structure data and information, (ii) closely connect evidence to theory and (iii) further develop theory. We present the hierarchy-of-hypotheses (HoH) approach to address these issues. In an HoH, hypotheses are conceptually and visually structured in a hierarchically nested way, where the lower branches can be directly connected to empirical results. Used as an evidence-driven, bottom-up approach, it can (i) show connections between empirical results, even when derived through diverse approaches; and (ii) indicate under which circumstances hypotheses are applicable. Used as a theory-driven, top-down method, it helps uncover mechanistic components of hypotheses. We offer guidance on how to build an HoH, provide examples from population and evolutionary biology and propose term...
The effects of overdispersion and zero inflation (e.g., poor model fits) can result in misinterpr... more The effects of overdispersion and zero inflation (e.g., poor model fits) can result in misinterpretation in studies using count data. These effects have not been evaluated in paleoecological studies of predation and are further complicated by preservational bias and time averaging. We develop a hierarchical Bayesian framework to account for uncertainty from overdispersion and zero inflation in estimates of specimen and predation trace counts. We demonstrate its application using published data on drilling predators and their prey in time-averaged death assemblages from the Great Barrier Reef, Australia. Our results indicate that estimates of predation frequencies are underestimated when zero inflation is not considered, and this effect is likely compounded by removal of individuals and predation traces via preservational bias. Time averaging likely reduces zero inflation via accumulation of rare taxa and events; however, it increases the uncertainty in comparisons between assemblage...
Site-selectivity analysis of drilling predation traces may provide useful behavioral information ... more Site-selectivity analysis of drilling predation traces may provide useful behavioral information concerning a predator interacting with its prey. However, traditional approaches exclude some spatial information (i.e., oversimplified trace position) and are dependent on the scale of analysis (e.g., arbitrary grid system used to divide the prey skeleton into sectors). Here we introduce the spatial point pattern analysis of traces (SPPAT), an approach for visualizing and quantifying the distribution of traces on shelled invertebrate prey, which includes improved collection of spatial information inherent to drillhole location (morphometric-based estimation), improved visualization of spatial trends (kernel density and hotspot mapping), and distance-based statistics for hypothesis testing (K-, L-, and pair correlation functions). We illustrate the SPPAT approach through case studies of fossil samples, modern beach-collected samples, and laboratory feeding trials of naticid gastropod pre...
As the climate changes and ecosystems shift toward novel combinations of species, the methods and... more As the climate changes and ecosystems shift toward novel combinations of species, the methods and metrics of conservation science are becoming less species-centric. To meet this growing need, marine conservation paleobiologists stand to benefit from the addition of new, taxon-free benthic indices to the live–dead analysis tool kit. These indices, which were developed to provide actionable, policy-specific data, can be applied to the readily preservable component of benthic communities (e.g., mollusks) to assess the ecological quality status of the entire community. Because these indices are taxon-free, they remain applicable even as the climate changes and novel communities develop—making them a potentially valuable complement to traditionally applied approaches for live–dead analysis, which tend to focus on maintaining specific combinations of species under relatively stable environmental conditions. Integrating geohistorical data with these established indices has potential to inc...
Philosophical Transactions of the Royal Society B: Biological Sciences
Conservation decision-making is a forward-looking process that involves choices among alternative... more 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 f...
Few shell-crushing predators can excavate prey living deep within the sediment. Despite this infa... more Few shell-crushing predators can excavate prey living deep within the sediment. Despite this infaunal refuge from predators, many deep-burrowing bivalves display a strikingly high incidence of shell damage when compared with species living at shallower depths. A non-predatory origin is necessary to explain this high incidence of injury. To evaluate the generality of this hypothesis, repair frequency (number of repairs per shell), along with position and geometry, were determined for 68 Neogene bivalve species from the US Atlantic and Gulf Coastal Plain, seven of which are classified as deep burrowers (>20 cm depth of sediment penetration). Panopea bitruncata, Panopea floridana, Panopea reflexa, and Panopea americana, which are among the deepest burrowers (up to 100 cm), have repair frequencies (2.8– 6.2) that are higher than any other species, while the value for Cyrtopleura costata (0.76) is exceeded only by semi-infaunal Atrina species (1.12). However, not all deep-burrowing sp...
We are among the scientists who have documented the environmental and ecological changes to the U... more We are among the scientists who have documented the environmental and ecological changes to the Upper Gulf of California following the reduction in the Colorado River’s flow. We object to any suggestion that our research supports Manjarrez-Bringas et al.’s conclusion that the decline in the Colorado River’s flow is the reason for the decline in the population of the endangered vaquita porpoise (Phocoena sinus). Manjarrez-Bringas et al.’s conclusions are incongruent with their own data, their logic is untenable, their analyses fail to consider current illegal fishing practices, and their recommendations are unjustified and misdirected. Vaquita face extinction because of bycatch, not because of the lack of river flow.
Conservation of species and ecosystems is increasingly difficult because anthropogenic impacts ar... more Conservation of species and ecosystems is increasingly difficult because anthropogenic impacts are pervasive and accelerating. Under this rapid global change, maximizing conservation success requires a paradigm shift from maintaining ecosystems in idealized past states toward facilitating their adaptive and functional capacities, even as species ebb and flow individually. Developing effective strategies under this new paradigm will require deeper understanding of the long-term dynamics that govern ecosystem persistence and reconciliation of conflicts among approaches to conserving historical versus novel ecosystems. Integrating emerging information from conservation biology, paleobiology, and the Earth sciences is an important step forward on the path to success. Maintaining nature in all its aspects will also entail immediately addressing the overarching threats of growing human population, overconsumption, pollution, and climate change.
Water management that alters riverine ecosystem processes has strongly influenced deltas and the ... more Water management that alters riverine ecosystem processes has strongly influenced deltas and the people who depend on them, but a full accounting of the trade-offs is still emerging. Using palaeoecological data, we document a surprising biogeochemical consequence of water management in the Colorado River basin. Complete allocation and consumptive use of the river's flow has altered the downstream estuarine ecosystem, including the abundance and composition of the mollusc community, an important component in estuarine carbon cycling. In particular, population declines in the endemic Colorado delta clam, Mulinia coloradoensis, from 50--125 individuals m(-2) in the pre-dam era to three individuals m(-2) today, have likely resulted in a reduction, on the order of 5900-15 000 t C yr(-1) (4.1-10.6 mol C m(-2) yr(-1)), in the net carbon emissions associated with molluscs. Although this reduction is large within the estuarine system, it is small in comparison with annual global carbon e...
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