Ocean deoxygenation is a growing concern globally. Oxygen is less soluble in warm water, and warming temperatures also result in the slowdown of ocean circulation which limits oxygen delivery to deeper waters. Anthropogenic eutrophication has also contributed to the development of hypoxic conditions in many coastal areas. Here we investigate biodiversity structure along an environmental gradient in the Gulf of Mexico to see how patterns of spatiotemporal turnover can inform future biotic response of benthos to ocean deoxygenation. Live and dead assemblages of bivalve mollusks were collected at 15 stations offshore Louisiana, Alabama, and Florida. Abundance and body size data were collected, and specimens were classified functionally using information about feeding, attachment, life position, and body size. Environmental conditions were characterized using multi-decadal mean sea surface temperature (SST), dissolved oxygen (DO), and net primary productivity (NPP), and grain size data from our field samples. Stations in the north-central Gulf affected by Mississippi River discharge are characterized by higher NPP, lower DO, and higher percentages of silt and clay than stations in the northeastern Gulf. Both taxonomic and functional diversity significantly covary with this environmental gradient, with the lowest diversities observed at stations in the core of Louisiana’s “dead zone.” Analyses of spatiotemporal turnover patterns reveal shifts in the dominant feeding mode, with hypoxic environments containing a greater abundance of deposit and mixed feeders, compared with more oxygenated environments that host an abundance of suspension feeders and are characterized by a greater variety of feeding ecologies. Live-dead analyses reveal a shift in taxonomic and functional diversity in coastal Louisiana, that appears to coincide with the onset of anthropogenic eutrophication in these coastal settings.
{"title":"Impacts of Ocean Deoxygenation on Marine Benthos in the Gulf of Mexico","authors":"P. Harnik, A. Chao, K. Collins, Marina C. Rillo","doi":"10.58782/flmnh.fgco6472","DOIUrl":"https://doi.org/10.58782/flmnh.fgco6472","url":null,"abstract":"Ocean deoxygenation is a growing concern globally. Oxygen is less soluble in warm water, and warming temperatures also result in the slowdown of ocean circulation which limits oxygen delivery to deeper waters. Anthropogenic eutrophication has also contributed to the development of hypoxic conditions in many coastal areas. Here we investigate biodiversity structure along an environmental gradient in the Gulf of Mexico to see how patterns of spatiotemporal turnover can inform future biotic response of benthos to ocean deoxygenation. Live and dead assemblages of bivalve mollusks were collected at 15 stations offshore Louisiana, Alabama, and Florida. Abundance and body size data were collected, and specimens were classified functionally using information about feeding, attachment, life position, and body size. Environmental conditions were characterized using multi-decadal mean sea surface temperature (SST), dissolved oxygen (DO), and net primary productivity (NPP), and grain size data from our field samples. Stations in the north-central Gulf affected by Mississippi River discharge are characterized by higher NPP, lower DO, and higher percentages of silt and clay than stations in the northeastern Gulf. Both taxonomic and functional diversity significantly covary with this environmental gradient, with the lowest diversities observed at stations in the core of Louisiana’s “dead zone.” Analyses of spatiotemporal turnover patterns reveal shifts in the dominant feeding mode, with hypoxic environments containing a greater abundance of deposit and mixed feeders, compared with more oxygenated environments that host an abundance of suspension feeders and are characterized by a greater variety of feeding ecologies. Live-dead analyses reveal a shift in taxonomic and functional diversity in coastal Louisiana, that appears to coincide with the onset of anthropogenic eutrophication in these coastal settings.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"2677 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131981217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The continent of Australia is currently warming approximately thirty-five percent faster than the rest of the globe, with the warmest year on record coinciding with the most extreme bush fires. While effects of ongoing climate change are apparent over the past century, Australia has experienced pronounced aridification since the Miocene/Pliocene, transitioning from tropical forests to more open habitats. To better contextualize on-going climate change, we assess the ecology and paleobiology of mammalian faunas in Australia from the Pliocene to the Present in the Darling Downs region of Queensland Australia. Via the analysis of stable isotopes from tooth enamel and dental microwear texture analysis of the chewing surfaces of teeth, we clarify the ecology and paleobiology of medium to large marsupials from the Pliocene Chinchilla Sands and Pleistocene Eastern Darling Downs faunas. By comparing these ancient marsupial mammal communities to extant marsupial mammals that inhabit these regions today, we further demonstrate that the most dramatic changes between past ecosystems are clearly between those of the Present and the Plio-Pleistocene—indicated that the Darling Downs region of today is disparate as compared to the past. Most notably, Macropus giganteus consumes vegetation that is ~5.6‰ higher in δ13C values today than during the past, indicating feeding in a significantly more open landscape. The Pliocene and Pleistocene of the Darling Downs are instead dominated by mixed-feeding and browsing taxa, with several taxa exhibiting diets disparate from modern analogues (e.g., an abundance of C4 browsers). Collectively, these deep-time temporal comparisons are a clear example of how ecological communities observed today do not represent the full range of ecological niches occupied in the past and highlight the dramatic climate-departures experienced today.
{"title":"Paleoecology of the Plio-Pleistocene of Queensland: Ecological Shifts Evidenced From Fauna at the Darling Downs","authors":"L. Desantis, G. Price, Julien Louys","doi":"10.58782/flmnh.xztv9346","DOIUrl":"https://doi.org/10.58782/flmnh.xztv9346","url":null,"abstract":"The continent of Australia is currently warming approximately thirty-five percent faster than the rest of the globe, with the warmest year on record coinciding with the most extreme bush fires. While effects of ongoing climate change are apparent over the past century, Australia has experienced pronounced aridification since the Miocene/Pliocene, transitioning from tropical forests to more open habitats. To better contextualize on-going climate change, we assess the ecology and paleobiology of mammalian faunas in Australia from the Pliocene to the Present in the Darling Downs region of Queensland Australia. Via the analysis of stable isotopes from tooth enamel and dental microwear texture analysis of the chewing surfaces of teeth, we clarify the ecology and paleobiology of medium to large marsupials from the Pliocene Chinchilla Sands and Pleistocene Eastern Darling Downs faunas. By comparing these ancient marsupial mammal communities to extant marsupial mammals that inhabit these regions today, we further demonstrate that the most dramatic changes between past ecosystems are clearly between those of the Present and the Plio-Pleistocene—indicated that the Darling Downs region of today is disparate as compared to the past. Most notably, Macropus giganteus consumes vegetation that is ~5.6‰ higher in δ13C values today than during the past, indicating feeding in a significantly more open landscape. The Pliocene and Pleistocene of the Darling Downs are instead dominated by mixed-feeding and browsing taxa, with several taxa exhibiting diets disparate from modern analogues (e.g., an abundance of C4 browsers). Collectively, these deep-time temporal comparisons are a clear example of how ecological communities observed today do not represent the full range of ecological niches occupied in the past and highlight the dramatic climate-departures experienced today.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"335 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116646804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jessica A. Oswald, Brian Smith, Julie M. Allen, R. Guralnick, D. Steadman, M. LeFebvre
Islands are windows for studying how humans have shaped biogeographic distributions. However, modern diversity patterns on islands are the outcome of evolutionary, ecological, and anthropocentric factors across long-temporal scales that often leave little evidence of the interactions among them. One exception are the parrots of the Caribbean which have a close commensal relationship with humans and an extensive fossil and archaeological record in the Holocene. Using modern and ancient DNA and radiocarbon dating, we present a temporal and spatial overview of the evolution, extirpation, and translocation of Amazona parrots across the Caribbean. Amazona colonized the Greater Antilles in the Pliocene and the most widespread parrot species, the Cuban Parrot, exhibits inter-island divergences throughout the Pleistocene. Within this radiation, we discovered a now extinct, genetically distinct lineage that survived on Turks & Caicos until human settlement of the islands. We also found that the narrowly distributed Hispaniolan Amazon had a range that once included the Bahamas and was introduced by indigenous people to Grand Turk and Montserrat. Our results show that datasets that transcend the extinct-living continuum highlight the long-term role of humans in altering the diversity and distribution of Caribbean biota.
{"title":"Human-Driven Diversity Changes in Caribbean Parrots Across the Holocene","authors":"Jessica A. Oswald, Brian Smith, Julie M. Allen, R. Guralnick, D. Steadman, M. LeFebvre","doi":"10.58782/flmnh.wvej4221","DOIUrl":"https://doi.org/10.58782/flmnh.wvej4221","url":null,"abstract":"Islands are windows for studying how humans have shaped biogeographic distributions. However, modern diversity patterns on islands are the outcome of evolutionary, ecological, and anthropocentric factors across long-temporal scales that often leave little evidence of the interactions among them. One exception are the parrots of the Caribbean which have a close commensal relationship with humans and an extensive fossil and archaeological record in the Holocene. Using modern and ancient DNA and radiocarbon dating, we present a temporal and spatial overview of the evolution, extirpation, and translocation of Amazona parrots across the Caribbean. Amazona colonized the Greater Antilles in the Pliocene and the most widespread parrot species, the Cuban Parrot, exhibits inter-island divergences throughout the Pleistocene. Within this radiation, we discovered a now extinct, genetically distinct lineage that survived on Turks & Caicos until human settlement of the islands. We also found that the narrowly distributed Hispaniolan Amazon had a range that once included the Bahamas and was introduced by indigenous people to Grand Turk and Montserrat. Our results show that datasets that transcend the extinct-living continuum highlight the long-term role of humans in altering the diversity and distribution of Caribbean biota.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114514312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Cramer, Loren McClenachan, L. Álvarez‐Filip, J. Carilli, J. Cope, R. Graham, Ilse Martínez, M. McField, J. Nowlis, Juan Carlos Pérez Jiménez, N. Rubio‐Cisneros, A. Tewfik, Tali Vardi, Zachary Whaley
Studies using paleoecological and historical data can inform coral reef management by providing accurate ecological baselines and by pinpointing the timing, magnitude, and drivers of ecosystem declines. However, these studies have rarely been incorporated into policy and management frameworks. This working group brings together paleontologists, historical ecologists, ecologists, fisheries scientists, and conservation practitioners to develop pathways for incorporating long-term ecological data into decision-making to advance the sustainable management of reef ecosystems. Our group is focusing on Caribbean coral reefs, a geography with an abundance of historical ecological data and a track record of collaboration between reef scientists and managers. This spirit of collaboration is enhanced by the immediacy of conservation needs for reef ecosystems in this region. We are focusing on the application of long-term data to two pressing management issues for Caribbean coral reefs, which together address the most urgent local human drivers of ecosystem change – fishing and land-based pollution. In this talk, I will outline our working group’s aims and progress to date.
{"title":"Integrating Paleo, Historical, Archeological, and Traditional Ecological Knowledge Data into Caribbean Coral Reef Management","authors":"K. Cramer, Loren McClenachan, L. Álvarez‐Filip, J. Carilli, J. Cope, R. Graham, Ilse Martínez, M. McField, J. Nowlis, Juan Carlos Pérez Jiménez, N. Rubio‐Cisneros, A. Tewfik, Tali Vardi, Zachary Whaley","doi":"10.58782/flmnh.kkvf4776","DOIUrl":"https://doi.org/10.58782/flmnh.kkvf4776","url":null,"abstract":"Studies using paleoecological and historical data can inform coral reef management by providing accurate ecological baselines and by pinpointing the timing, magnitude, and drivers of ecosystem declines. However, these studies have rarely been incorporated into policy and management frameworks. This working group brings together paleontologists, historical ecologists, ecologists, fisheries scientists, and conservation practitioners to develop pathways for incorporating long-term ecological data into decision-making to advance the sustainable management of reef ecosystems. Our group is focusing on Caribbean coral reefs, a geography with an abundance of historical ecological data and a track record of collaboration between reef scientists and managers. This spirit of collaboration is enhanced by the immediacy of conservation needs for reef ecosystems in this region. We are focusing on the application of long-term data to two pressing management issues for Caribbean coral reefs, which together address the most urgent local human drivers of ecosystem change – fishing and land-based pollution. In this talk, I will outline our working group’s aims and progress to date.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114777112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Conservation biology, and the descendent discipline conservation paleobiology, are philosophically aligned with the mission of the National Park Service (NPS), including near time and deep time frameworks. As defined in the Organic Act of August 25, 1916, the purpose and mission of the NPS is “…to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations”. This conservation mandate is broadly inclusive of grizzly bears, redwood trees, and dinosaur bones equally, throughout the 424 officially designated parks, monuments, and other areas managed by the NPS. Although conservation paleobiology is reported by some to be a new and integrated field of study, there are remarkable similarities to traditional and old school perspectives which embraced natural history more holistically during the nineteenth and early twentieth centuries. Notably, the written contributions by Charles Darwin, Aldo Leopold, and Edward Abbey synthesize observations at the global and landscape scales, promoting conservation advocacy of the natural world, past and present. U.S. National Park Service areas preserve some of Planet Earth’s most globally significant natural resources, ecological systems, and biosphere reserves. Discoveries of fossil condors and mummified bats within caves of Grand Canyon National Park, the co-occurrence of human and megafaunal footprints preserved in Late Pleistocene strata at White Sands National Park, and pygmy mammoth remains on Channel Islands National Park, collectively demonstrate how valuable temporal and historical biological perspectives contribute to science, stewardship, and resources management in parks and beyond. The paleobiology community is cordially invited to join in the holistic study and conservation of the near time and deep time resources in the national parks.
{"title":"Conservation Paleobiology and the Stewardship of U.S. National Park Service Paleontological Resources","authors":"V. Santucci","doi":"10.58782/flmnh.dtxe7925","DOIUrl":"https://doi.org/10.58782/flmnh.dtxe7925","url":null,"abstract":"Conservation biology, and the descendent discipline conservation paleobiology, are philosophically aligned with the mission of the National Park Service (NPS), including near time and deep time frameworks. As defined in the Organic Act of August 25, 1916, the purpose and mission of the NPS is “…to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations”. This conservation mandate is broadly inclusive of grizzly bears, redwood trees, and dinosaur bones equally, throughout the 424 officially designated parks, monuments, and other areas managed by the NPS. Although conservation paleobiology is reported by some to be a new and integrated field of study, there are remarkable similarities to traditional and old school perspectives which embraced natural history more holistically during the nineteenth and early twentieth centuries. Notably, the written contributions by Charles Darwin, Aldo Leopold, and Edward Abbey synthesize observations at the global and landscape scales, promoting conservation advocacy of the natural world, past and present. U.S. National Park Service areas preserve some of Planet Earth’s most globally significant natural resources, ecological systems, and biosphere reserves. Discoveries of fossil condors and mummified bats within caves of Grand Canyon National Park, the co-occurrence of human and megafaunal footprints preserved in Late Pleistocene strata at White Sands National Park, and pygmy mammoth remains on Channel Islands National Park, collectively demonstrate how valuable temporal and historical biological perspectives contribute to science, stewardship, and resources management in parks and beyond. The paleobiology community is cordially invited to join in the holistic study and conservation of the near time and deep time resources in the national parks.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124346814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paleoecology studies provide pre-instrument data from the Everglades painting an informative picture of physical, biological, and ecological conditions prior to human intervention. Because Florida’s development history is relatively recent, and because observational data span only the last half-century, managers rely on paleoecology data as the basis for important decisions regarding multi-decadal and expensive restoration. Effective restoration depends strongly on the establishment of restoration targets, especially pre-development vegetation and hydropatterns (flow, depth, timing, distribution). Coring data were instrumental in the reconstruction of paleo hydrologic and vegetation trends in the ARM Loxahatchee National Wildlife Refuge, helping managers understand the magnitude and causes of 20th century problems. Similarly, sediment cores from the Big Cypress National Preserve led managers to understand that the development of marl prairies in Everglades National Park – critical habitat for the endangered Cape Sable Seaside Sparrow – was a 20th century phenomenon resulting from past water management practices. Finally, paleoecological and modeling studies in Florida Bay and the Everglades for the $20B+ Comprehensive Everglades Restoration plan established freshwater flow targets now used by managers. Although restoration of historic freshwater flow is not feasible, knowledge about Everglades hydrology and ecology prior to human intervention plays a pivotal role in the design, selection, and construction of restoration projects. Paleoecological data, coupled with decadal-scale monitoring and other long-term studies, provide the long-term perspective necessary to understand decadal, to centennial, and to millennial time-scale processes. While these data are cost-effective to procure, a long-term commitment to funding these types of studies is essential to provide the scientific foundation for restoration.
{"title":"The Importance of Paleoecology in Everglades Restoration Science and Management","authors":"N. Aumen, Georgiana Wingard, C. Bernhardt","doi":"10.58782/flmnh.whwa9153","DOIUrl":"https://doi.org/10.58782/flmnh.whwa9153","url":null,"abstract":"Paleoecology studies provide pre-instrument data from the Everglades painting an informative picture of physical, biological, and ecological conditions prior to human intervention. Because Florida’s development history is relatively recent, and because observational data span only the last half-century, managers rely on paleoecology data as the basis for important decisions regarding multi-decadal and expensive restoration. Effective restoration depends strongly on the establishment of restoration targets, especially pre-development vegetation and hydropatterns (flow, depth, timing, distribution). Coring data were instrumental in the reconstruction of paleo hydrologic and vegetation trends in the ARM Loxahatchee National Wildlife Refuge, helping managers understand the magnitude and causes of 20th century problems. Similarly, sediment cores from the Big Cypress National Preserve led managers to understand that the development of marl prairies in Everglades National Park – critical habitat for the endangered Cape Sable Seaside Sparrow – was a 20th century phenomenon resulting from past water management practices. Finally, paleoecological and modeling studies in Florida Bay and the Everglades for the $20B+ Comprehensive Everglades Restoration plan established freshwater flow targets now used by managers. Although restoration of historic freshwater flow is not feasible, knowledge about Everglades hydrology and ecology prior to human intervention plays a pivotal role in the design, selection, and construction of restoration projects. Paleoecological data, coupled with decadal-scale monitoring and other long-term studies, provide the long-term perspective necessary to understand decadal, to centennial, and to millennial time-scale processes. While these data are cost-effective to procure, a long-term commitment to funding these types of studies is essential to provide the scientific foundation for restoration.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121089123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Bloch, P. Morse, N. Vitek, D. Boyer, Vera A. Korasidis, S. Wing
Abilities of taxa to track suitable habitat under climate change is a concern in conservation biology. Projections that assume suitable habitat is limited to currently occupied biomes can produce underestimates of species viability. The geological record is a valuable source of data to test assumptions about habitat tracking because it archives past episodes of climate change. The Paleocene-Eocene Thermal Maximum (PETM) ~56 million years ago was an interval of rapid carbon release (millennial scale) and global warming (~5 C) that caused large geographic range shifts in Earth’s biota. Large, stratigraphically controlled fossil collections spanning the PETM in the Bighorn Basin, Wyoming, document first occurrence data for immigrant mammals and plants, providing evidence of geographic range shifts as well as changes in climate, flora and vegetation. If mammals tracked specific habitats, their intercontinental dispersal would imply continuity of biomes across Holarctica. In that case, intercontinental mammal and plant immigrants should appear concurrently. Instead, mammalian immigrants crossed high latitude belts of warm, temperate forest, then appeared in the Bighorn Basin during the warmest part of the PETM when plant fossils suggest a dry tropical forest. Warm temperate Eurasian plants are rare during the body of the PETM, but become abundant during the recovery, as climate became wetter. Floral change during the PETM recovery is not concurrent with change in mammalian community structure. Distinct patterns of mammalian and plant turnover suggest that mammals did not strictly track plant-defined habitats. Species may be capable of more flexible responses to rapid climate change than current models predict. Efforts that support movement and provide multi-latitudinal networks of protected areas should be prioritized as a viable means to help conserve some species in the face of climate change.
{"title":"Implications of Immigrant Arrival Times During the Paleocene-Eocene Thermal Maximum for Mammal Biogeographic Response to Modern Climate Change","authors":"J. Bloch, P. Morse, N. Vitek, D. Boyer, Vera A. Korasidis, S. Wing","doi":"10.58782/flmnh.pyuj3341","DOIUrl":"https://doi.org/10.58782/flmnh.pyuj3341","url":null,"abstract":"Abilities of taxa to track suitable habitat under climate change is a concern in conservation biology. Projections that assume suitable habitat is limited to currently occupied biomes can produce underestimates of species viability. The geological record is a valuable source of data to test assumptions about habitat tracking because it archives past episodes of climate change. The Paleocene-Eocene Thermal Maximum (PETM) ~56 million years ago was an interval of rapid carbon release (millennial scale) and global warming (~5 C) that caused large geographic range shifts in Earth’s biota. Large, stratigraphically controlled fossil collections spanning the PETM in the Bighorn Basin, Wyoming, document first occurrence data for immigrant mammals and plants, providing evidence of geographic range shifts as well as changes in climate, flora and vegetation. If mammals tracked specific habitats, their intercontinental dispersal would imply continuity of biomes across Holarctica. In that case, intercontinental mammal and plant immigrants should appear concurrently. Instead, mammalian immigrants crossed high latitude belts of warm, temperate forest, then appeared in the Bighorn Basin during the warmest part of the PETM when plant fossils suggest a dry tropical forest. Warm temperate Eurasian plants are rare during the body of the PETM, but become abundant during the recovery, as climate became wetter. Floral change during the PETM recovery is not concurrent with change in mammalian community structure. Distinct patterns of mammalian and plant turnover suggest that mammals did not strictly track plant-defined habitats. Species may be capable of more flexible responses to rapid climate change than current models predict. Efforts that support movement and provide multi-latitudinal networks of protected areas should be prioritized as a viable means to help conserve some species in the face of climate change.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134225413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abiotic and biotic environmental factors shape species behavioral, physiological, and morphological traits. Shifts in the diversity of these functional traits therefore can serve as an indicator of spatial and temporal changes in environmental conditions. In recent centuries, the delivery of nutrients to coastal ecosystems has increased markedly through changing waste management and land-use practices. Nutrient enrichment has increased rates of primary productivity, resulting in greater organic accumulation on the seafloor and the development of hypoxic conditions in some areas, due to the aerobic decomposition of phytoplankton blooms. Anthropogenic eutrophication and associated hypoxia have been monitored annually in the northern Gulf of Mexico for over four decades, with an emphasis on areas surrounding the Mississippi River Delta. To further understand how anthropogenic eutrophication affects functional diversity in benthic marine communities, we collected live and dead assemblages of bivalve mollusks from surficial sediments at five stations along the -20 meters isobath in coastal Alabama. Bivalves were categorized into functional groups using information about their mobility, fixation, feeding type, substrate preference, and body size. Consistent with our hypotheses, preliminary results indicate a temporal shift from benthic communities dominated primarily by epifaunal and infaunal suspension-feeding species to communities characterized primarily by deposit feeders, many of which dwell on the seafloor surface. Ongoing analyses will help identify the functional traits that are most sensitive to these changing environmental conditions. Understanding functional diversity shifts in the recent past can provide insight into how anthropogenic eutrophication may further impact benthic marine ecosystems in the future.
{"title":"Live-Dead Shifts in Molluscan Functional Diversity in Coastal Alabama","authors":"Charlotte Filipovich, P. Harnik, K. Collins","doi":"10.58782/flmnh.xkhw5897","DOIUrl":"https://doi.org/10.58782/flmnh.xkhw5897","url":null,"abstract":"Abiotic and biotic environmental factors shape species behavioral, physiological, and morphological traits. Shifts in the diversity of these functional traits therefore can serve as an indicator of spatial and temporal changes in environmental conditions. In recent centuries, the delivery of nutrients to coastal ecosystems has increased markedly through changing waste management and land-use practices. Nutrient enrichment has increased rates of primary productivity, resulting in greater organic accumulation on the seafloor and the development of hypoxic conditions in some areas, due to the aerobic decomposition of phytoplankton blooms. Anthropogenic eutrophication and associated hypoxia have been monitored annually in the northern Gulf of Mexico for over four decades, with an emphasis on areas surrounding the Mississippi River Delta. To further understand how anthropogenic eutrophication affects functional diversity in benthic marine communities, we collected live and dead assemblages of bivalve mollusks from surficial sediments at five stations along the -20 meters isobath in coastal Alabama. Bivalves were categorized into functional groups using information about their mobility, fixation, feeding type, substrate preference, and body size. Consistent with our hypotheses, preliminary results indicate a temporal shift from benthic communities dominated primarily by epifaunal and infaunal suspension-feeding species to communities characterized primarily by deposit feeders, many of which dwell on the seafloor surface. Ongoing analyses will help identify the functional traits that are most sensitive to these changing environmental conditions. Understanding functional diversity shifts in the recent past can provide insight into how anthropogenic eutrophication may further impact benthic marine ecosystems in the future.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115177927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Mississippi River delivers vast quantities of nutrient-rich freshwater to the northern Gulf of Mexico, fueling primary productivity in the coastal zone. Aerobic decomposition of these phytoplankton blooms has resulted in one of the most extensive dead zones on Earth. In contrast, primary productivity and hypoxia are more limited in the northeastern Gulf, where coastal environments are fed by smaller watersheds. How do environmental factors such as primary productivity, oxygen availability, and sea surface temperature shape coastal food webs? Here, we investigate environmental correlates of predator and prey body size in benthic mollusks using Holocene death assemblages. Results of linear mixed effects models indicate that bivalve size and the frequency of drilling predation are both influenced by dissolved oxygen concentrations; bivalve size increases and drilling frequency decreases with declining oxygen levels. Sea surface temperature is positively associated with predator and prey size, whereas net primary productivity has little effect on the size of predators or prey. Predator-to-prey size ratios were not significantly associated with any of the environmental factors considered. Larger bivalves found in oxygen-limited areas may be due to decreased predation pressure, resulting in greater prey longevity. Warmer waters with sufficient dissolved oxygen may also provide suitable growth conditions to increase the size of bivalves and predatory gastropods. Holocene death assemblages can be used to test long-standing hypotheses regarding environmental controls on predator-prey body size distributions through geologic time and provide baselines for assessing the ongoing effects of anthropogenic eutrophication and warming on coastal food webs.
{"title":"Environmental Controls on Predator and Prey Body Size in the Northern Gulf of Mexico","authors":"L. Calderaro, P. Harnik, Marina C. Rillo","doi":"10.58782/flmnh.ynof4861","DOIUrl":"https://doi.org/10.58782/flmnh.ynof4861","url":null,"abstract":"The Mississippi River delivers vast quantities of nutrient-rich freshwater to the northern Gulf of Mexico, fueling primary productivity in the coastal zone. Aerobic decomposition of these phytoplankton blooms has resulted in one of the most extensive dead zones on Earth. In contrast, primary productivity and hypoxia are more limited in the northeastern Gulf, where coastal environments are fed by smaller watersheds. How do environmental factors such as primary productivity, oxygen availability, and sea surface temperature shape coastal food webs? Here, we investigate environmental correlates of predator and prey body size in benthic mollusks using Holocene death assemblages. Results of linear mixed effects models indicate that bivalve size and the frequency of drilling predation are both influenced by dissolved oxygen concentrations; bivalve size increases and drilling frequency decreases with declining oxygen levels. Sea surface temperature is positively associated with predator and prey size, whereas net primary productivity has little effect on the size of predators or prey. Predator-to-prey size ratios were not significantly associated with any of the environmental factors considered. Larger bivalves found in oxygen-limited areas may be due to decreased predation pressure, resulting in greater prey longevity. Warmer waters with sufficient dissolved oxygen may also provide suitable growth conditions to increase the size of bivalves and predatory gastropods. Holocene death assemblages can be used to test long-standing hypotheses regarding environmental controls on predator-prey body size distributions through geologic time and provide baselines for assessing the ongoing effects of anthropogenic eutrophication and warming on coastal food webs.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134032881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Grace, R. Akçakaya, Aaron Avery, Clare Duncan, J. Hansford, G. Herbert, A. Kramer, P. Mannion, A. Prohaska, Harri Ravenscroft, Ana Rodrigues, E. Saupe, P. Stephenson, S. Turvey, J. Welch, Jack Williams
This talk will describe the work of the CPN Pre-Impact Baselines Working Group to leverage the wealth of paleoecological and historical ecological data to facilitate estimation of pre-impact species distribution baselines. Species conservation has long focused on preventing human-driven extinctions, and over the past 50 years conservation success has been measured using changes in species’ extinction risk. However, recently calls have been made for a parallel focus on species recovery, and on developing metrics with which to assess its achievement. This call to action within the conservation community is fuelled in part by the recognition that baselines of species abundance and distribution have shifted dramatically across human generations with globally detectable human impacts on ecosystems beginning at least several thousand years ago. While assessment of extinction risk generally only considers species’ change over the past few decades, assessment of recovery requires considering change over centuries to millennia. This requires identifying the baseline status at the time when humans first became a major factor influencing the abundance and distribution of a species. Two new frameworks for considering conservation status relative to a species’ pre-impact baseline have been recently released: EPOCH (Evaluation of POpulation CHange), and the IUCN Green Status of Species. These frameworks have been lauded as moving conservation in a much-needed direction, but there is also concern about whether these methods will be applicable to any but a few well-known, charismatic species. Using a combination of modelling approaches, we are working to estimate species pre-impact distributions in a way that is accessible to conservation practitioners, helping to unshift the baseline and bring species recovery into the mainstream.
{"title":"Modeling Pre-Impact Baselines at Scale to Inform Species Recovery","authors":"M. Grace, R. Akçakaya, Aaron Avery, Clare Duncan, J. Hansford, G. Herbert, A. Kramer, P. Mannion, A. Prohaska, Harri Ravenscroft, Ana Rodrigues, E. Saupe, P. Stephenson, S. Turvey, J. Welch, Jack Williams","doi":"10.58782/flmnh.wosu1828","DOIUrl":"https://doi.org/10.58782/flmnh.wosu1828","url":null,"abstract":"This talk will describe the work of the CPN Pre-Impact Baselines Working Group to leverage the wealth of paleoecological and historical ecological data to facilitate estimation of pre-impact species distribution baselines. Species conservation has long focused on preventing human-driven extinctions, and over the past 50 years conservation success has been measured using changes in species’ extinction risk. However, recently calls have been made for a parallel focus on species recovery, and on developing metrics with which to assess its achievement. This call to action within the conservation community is fuelled in part by the recognition that baselines of species abundance and distribution have shifted dramatically across human generations with globally detectable human impacts on ecosystems beginning at least several thousand years ago. While assessment of extinction risk generally only considers species’ change over the past few decades, assessment of recovery requires considering change over centuries to millennia. This requires identifying the baseline status at the time when humans first became a major factor influencing the abundance and distribution of a species. Two new frameworks for considering conservation status relative to a species’ pre-impact baseline have been recently released: EPOCH (Evaluation of POpulation CHange), and the IUCN Green Status of Species. These frameworks have been lauded as moving conservation in a much-needed direction, but there is also concern about whether these methods will be applicable to any but a few well-known, charismatic species. Using a combination of modelling approaches, we are working to estimate species pre-impact distributions in a way that is accessible to conservation practitioners, helping to unshift the baseline and bring species recovery into the mainstream.","PeriodicalId":106523,"journal":{"name":"Bulletin of the Florida Museum of Natural History","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125221686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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