The emergence of an ecological community in evolutionary time is the result of species evolution and coevolution. In species rich and functionally diverse communities, there are a multitude of alternative pathways along which emergence could proceed. Nevertheless, analysis of alternative pathways for paleocommunities spanning more than 13 million years of the Permian-Triassic of the Karoo Basin of South Africa, suggests that pathways actually taken represent a small subset of the total available. This leads to a narrow representation of the total number of communities possible given a specific number of species and level of functional diversity. Furthermore, the paleocommunities were always superior to structural alternatives of equal complexity, in terms of community global stability (the number of species that can coexist stably and indefinitely). Such optimization could indicate a selective process during the formation of types of communities, or simply be emergent from the coevolutionary framework. Here we present ongoing work to support an emergent process by which many alternative types of communities may form constantly on ecological timescales, but where few are stable and persistent on longer timescales. This leads to the compositional stability of paleoecological units often noted in the fossil record, and the apparent incumbency of long-lasting lineages. The aftermath of mass extinctions present opportunities to test this hypothesis, because previously persistent communities are replaced by newly emergent ones, and the emergence process itself can be extended to geological timescales because of ongoing environmental instability, and the time required for the reformation of coevolutionary relationships and functional structures. Such is the case in the aftermath of the Permian-Triassic mass
extinction, when Early Triassic paleocommunities in the Karoo Basin were sub-optimal compared to alternative, hypothetical histories. Understanding long-term ecological persistence is crucial to our understanding of the modern anthropogenically-driven environmental crisis. Modern ecosystems are the documented products of geological and evolutionary history. Species acclimatization and adaptation to ongoing changes are not necessarily guarantees of the future persistence of the resulting reorganized
systems. It will become critical to determine if the biosphere has already turned down new ecological
and evolutionary pathways, or is still operating in the capacity of the pre-Anthropocene system.
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This content will become publicly available on September 28, 2024
Conservation biology and conservation paleobiology meet the Anthropocene together: history matters
As a species, we have reached a tipping point for Earth derived from our unsustainable resource use. While conservation efforts occurred early in human civilization, it was not until 1980 that the full force of environmental destruction, including the Santa Barbara oil spill in the 1970s, culminated in the new discipline of conservation biology focused on the biosphere. Similarly, conservation paleobiology, named two decades later, brings the unique perspective of the fossil record to conservation efforts, uniting biosphere and geosphere scientists. To date, conservation history does not include paleontological or geological perspectives. Further, each discipline has a different benchmark—near time—for when Earth’s ecosystems were modified by humans. Accordingly, the history of conservation efforts leading up to conservation biology and conservation paleobiology was examined from a geological and ecological framework. To provide a benchmark for near time, the hominin record and their geo-environmental modifications were also examined and revealed that by the start of the Holocene, all continents except ice-covered Antarctica and Greenland had human-modified ecosystems. Therefore, near time is dispensable when the Holocene Epoch is universally understood and precisely defined as a time when H. sapiens dominated environments. Lastly, a conservation corps is urgently needed, following the long tradition of F.D. R.’s Civilian Conservation Corps of the 1930s and J.F. Kennedy’s Peace Corps of the 1960s, to promote a global network connecting all students and practitioners of conservation disciplines to focus on biotic resilience, recovery, and solutions for the world’s most pressing environmental problems.
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- Award ID(s):
- 1745057
- NSF-PAR ID:
- 10489532
- Editor(s):
- Libermann, Bruce
- Publisher / Repository:
- Frontiers in Earth Sciences
- Date Published:
- Journal Name:
- Frontiers in Earth Science
- Edition / Version:
- 1
- Volume:
- 11
- ISSN:
- 2296-6463
- Page Range / eLocation ID:
- 1-21
- Subject(s) / Keyword(s):
- ["Conservation Biology, Conservation Paleobiology, hominins, near time, deep time, Holocene"]
- Format(s):
- Medium: X Size: 2 mb Other: pdf
- Size(s):
- ["2 mb"]
- Sponsoring Org:
- National Science Foundation
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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.
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Shifting baselines can skew species harvest guidelines and lead to potentially inaccurate assessments of population status and range. The North American Fur Trade (~1600–1900 CE) profoundly impacted the continent’s socio-ecological systems, but its legacies are often not incorporated in management discussions. We apply a conservation paleobiology lens to address shifting baselines of nine species of fur-bearing mammals in Vermont, including seven mesocarnivores and two semi-aquatic rodents. Using a database maintained by the Vermont Division for Historic Preservation, we identified 25 existing radiocarbon dates of fur-bearer associated features from 16 archaeological localities spanning the Early-Late Holocene. We also generated 7 new radiocarbon dates on beaver and muskrat bones from the Ewing (VT-CH-005), Bohannon (VT-GI-026), and Chimney Point (VT-AD-329) localities. Our new radiocarbon dates cluster within the Late Holocene, immediately prior to and throughout the European contact period, and overlap with The Beaver Wars. We recover a ~8,000 year record of beaver harvest, affirming the millennial scale importance of beavers, a species that is often the focus of human-wildlife conflict research. Comparison of zooarchaeological occurrences with digitized natural history specimens and community science observations reveals geographic range continuity for most species except for the American marten, which was historically extirpated, and confirms the native status of the red fox. While taphonomic constraints make our dataset a conservative assessment, our case studies demonstrate how wildlife managers can employ zooarchaeological data to better understand long-term properties of coupled socio-ecological systems and highlight the cultural importance of these species to Indigenous trade networks prior to the Fur Trade in Vermont.more » « less
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Abstract Aim Ongoing and future anthropogenic climate change poses one of the greatest threats to biodiversity, affecting species distributions and ecological interactions. In the Amazon, climatic changes are expected to induce warming, disrupt precipitation patterns and of particular concern, to increase the intensity and frequency of droughts. Yet the response of ecosystems to intense warm, dry events is not well understood. In the Andes the mid‐Holocene dry event (MHDE),
c. 9,000 to 4,000 years ago, was the warmest and driest period of the last 100,000 years which coincided with changes in evaporation and precipitation that caused lake levels to drop over most of tropical South America. This event probably approximates our near‐climatic future, and a critical question is:How much did vegetation change in response to this forcing? Location Lake Pata, Brazilian Western Amazonia.
Taxon Terrestrial and aquatic plants.
Methods We used pollen, charcoal, total organic carbon (TOC), total nitrogen (TN), δ13C and δ15N data from a new high‐resolution core that spans the last
c. 7,600 years history of Lake Pata.Results We found that in the wettest section of Amazonia changes associated with the MHDE were detected in the geochemistry analysis but that vegetation changed very little in response to drought during the Holocene. This is the first high‐resolution core without apparent hiatuses that spans most of the Holocene (last 7,600 cal yr
bp ) from Lake Pata, Brazil. Changes in the organic geochemistry of sediments indicated that between c. 6,500 and 3,600 cal yrbp lake levels dropped. Vegetation, however, showed little change as near‐modern forests were seen throughout the record, evidencing the substantial resilience of this system. Only a few species replacements and minor fluctuations in abundance were observed in the pollen record.Main conclusions The mid‐Holocene warming and reduced precipitation had a limited impact on western Amazonian forests. We attribute much of the resilience to a lack of fire in this system, and that if human‐set fires were to be introduced, the forest destruction from that cause would override that induced by climate alone.
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The Amundsen Sea sector of Antarctica has long been considered the most vulnerable part of the West Antarctic Ice Sheet (WAIS) because of the great water depth at the grounding line, a subglacial bed seafloor deepening toward the interior of the continent, and the absence of substantial ice shelves. Glaciers in this configuration are thought to be susceptible to rapid or runaway retreat. Ice flowing into the Amundsen Sea Embayment is undergoing the most rapid changes of any sector of the Antarctic ice sheets outside the Antarctic Peninsula, including substantial grounding-line retreat over recent decades, as observed from satellite data. Recent models suggest that a threshold leading to the collapse of WAIS in this sector may have been already crossed and that much of the ice sheet could be lost even under relatively moderate greenhouse gas emission scenarios. Drill cores from the Amundsen Sea provide tests of several key questions about controls on ice sheet stability. 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To test the hypothesis that WAIS collapses occurred during the Neogene and Quaternary and, if so, when and under which environmental conditions; 2. To obtain ice-proximal records of ice sheet dynamics in the Amundsen Sea that correlate with global records of ice-volume changes and proxy records for atmospheric and ocean temperatures; 3. To study the stability of a marine-based WAIS margin and how warm deepwater incursions control its position on the shelf; 4. To find evidence for the earliest major grounded WAIS advances onto the middle and outer shelf; 5. To test the hypothesis that the first major WAIS growth was related to the uplift of the Marie Byrd Land dome. International Ocean Discovery Program (IODP) Expedition 379 completed two very successful drill sites on the continental rise of the Amundsen Sea. Site U1532 is located on a large sediment drift, now called the Resolution Drift, and it penetrated to 794 m with 90% recovery. 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