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The Neotoma Paleoecology Database (Neotoma) is an open international data resource that stores and shares multiple kinds of fossil, paleoecological, and paleoenvironmental data. [1] Neotoma specializes in fossil data holdings at timescales covering the last several decades to the last several million years. Neotoma is organized and led by scientists and enhances data consistency through community curation by experts. Neotoma data are open to all and available to anyone with an internet connection.
Neotoma data are used by scientists and teachers (especially paleoecologists, biogeographers, and archaeologists) to study the responses of species and ecosystems to past environmental change and growing human activity. Paleoclimatologists use Neotoma data to help reconstruct past climates. [2] Sample research questions addressed include: 1) How sensitive are ecosystems to past climate change. [3] 2) Why were rates of tree range expansion so fast after the end of the last ice age, given that tree seed dispersal distances are usually so short (Reid's Paradox)? 3) Where and when did humans begin transforming ecosystems? [4] 4) What were the causes and consequences of the widespread extinctions of large animals over the last 50,000 years? [5] [6] 5) Which ecosystems are characterized by abrupt change between alternate stable states and what triggers these abrupt changes? [7] 6) How have freshwater resources and aquatic ecosystems been affected by human land use and activity over the last several decades? [8] [9]
The species and taxa stored in Neotoma represent a breadth of terrestrial and aquatic organisms: plants (pollen and larger fossils), mammals and other vertebrates, insects and other invertebrates, diatoms, ostracodes, and testate amoebae. Neotoma also stores the age estimates provided by radiometric dating (e.g. radiocarbon, lead-210) and the age estimates that are derived from statistical models of age as a function of depth in sediment column. The Neotoma data model is extensible to other types of paleoecological and paleoenvironmental variables.
Data volume in Neotoma is growing rapidly, as are the data holdings in other paleontological and contemporary databases. [10] As of May 2020, Neotoma held 7 million individual observations from over 38,700 datasets, 18,600 sites, 7,000 scientific papers, 6,000 authors, and 100 countries [1]. For comparison, On Nov 8, 2017, Neotoma held 3.8 million observations, from 17,275 datasets and 9,269 sites. [11]
The intellectual foundations of Neotoma trace back to efforts by early paleontologists and paleoecologists in the first half of the 20th century to assemble many individual records into larger mapped syntheses. [12] As von Post wrote, paleoecologists must "think horizontally, work vertically," [13] i.e. think across both time and space to understand the processes governing the ever-changing distribution of species, the associations among species, and the diversity of life.
These efforts accelerated in the 1970s and 1980s, when a number of scientific teams began assembling databases of fossil distributions to study the spatial distributions of species over space and time and the effects of past environmental variations on these distributions. These efforts were powered by advances in computing capabilities and the growing availability of radiocarbon and other radiometric dates to provide a common time framework for all fossil occurrences. Much of this work focused on environmental and ecological changes accompanying the glacial-interglacial cycles of the Quaternary. These databases were used both by paleoclimatologists to draw inferences about past climates that could be used to test the paleoclimatic simulations of earth system models, [14] and by paleoecologists interested in how past community dynamics were driven by these environmental changes. [15] [16] For example, Margaret Davis demonstrated tree species experienced large range shifts with the climate changes at the end of the last ice age and that species responded individualistically. [17] As a result, many past communities were 'no analog,' i.e. their mixtures of species lack any close counterpart in modern communities. Some records and Constituent Databases in Neotoma extend deeper into the Cenozoic.
In parallel, other research teams were gathering fossil records from high-resolution sediment archives spanning the last few decades to centuries to study the effects of human activities upon communities and ecosystems. Examples include the effects of acid rain on ecosystems in the 1980s, [18] or the eutrophication of many lake ecosystems due to increasing nutrient runoff into lakes and streams. [19] [20]
Many of these initial data-gathering efforts were led by individual pioneers (e.g. Margaret Davis, Tom Webb, Russ Graham, Bjorn Berglund, Jacques-Louis Beaulieu) or by small research teams. As these efforts have matured and as the amount of data has grown, the volume and complexity of paleoecological data is now beyond the capacity of any single individual expert to manage or curate. At the same time, many smaller paleontological and paleoecological databases have been unable to keep up with current advances in informatics, or have gone offline as funding lapsed or lead investigators retired or moved on.
Hence, the fields of paleoecology and paleontology have developed data governance models based on community curation, in which data resources like Neotoma are managed by communities of scientists working together to curate and share their data. [11] Neotoma follows a model of centralized informatics but distributed scientific governance, and is best viewed as a coalition of Constituent Databases that share a common set of database and software resources, while retaining separate rights to govern and curate the data in their Data Stewards' domains of expertise. For example, the European Pollen Database uses the Neotoma data model and software services, but is governed by its own board and community of expert data stewards.
Neotoma works closely with the Paleobiology Database, which has a similar intellectual history, but has focused on the entire history of life, at timescales of millions to hundreds of millions of years. Together, Neotoma and the Paleobiology Database have helped launch the EarthLife Consortium, a non-profit umbrella organization to support the easy and free sharing of paleoecological and paleobiological data.
Neotoma employs a model of distributed data curation and governance. In this model, Neotoma data are curated and governed by a community of Data Stewards, organized into Constituent Databases. [11] [12] These Constituent Databases can be organized by region, time, or taxonomic group. For example, FAUNMAP is a Constituent Database in Neotoma that manages Quaternary fossil vertebrate records in North America, while MioMap primarily emphasizes Miocene vertebrate records. [21] For pollen data, Constituent Databases are organized geographically and include the European Pollen Database, [22] [23] the North American Pollen Database, and the Latin American Pollen Database. [24] Other major Constituent Databases include the Testate Amoebae Database, [25] the International Ostracode Database, and the Diatom Paleoecology Data Cooperative. All data in Neotoma are uploaded and curated by Data Stewards associated with one or more Constituent Databases. This model of distributed community curation is essential to ensuring data quality and consistency.
Neotoma is led by a Neotoma Leadership Council (NLC) comprising 14 elected councilors, of which 2 seats are reserved for early career scientists (Bylaws). Elections are held annually, with roughly one-third of the NLC elected each cycle.
Neotoma is a recommended data facility for the Earth Sciences Division of the National Science Foundation, Past Global Changes, and the American Quaternary Association. Neotoma is a member of the ICSU World Data System and is registered with COPDESS registry for scientific data sources adhering to FAIR (Findable, Accessible, Interoperable, Reproducible) principles. Neotoma has been supported by multiple sources, including the National Science Foundation and the Belmont Forum.
Use of data in Neotoma is governed by a Creative Commons NC-BY license, which permits unrestricted use as long as data sources are properly acknowledged and cited (Neotoma Data Use Policy). Proper full citation of data in Neotoma occurs at three levels: Neotoma itself, the governing Constituent Database(s), and the original authors.
Data can be retrieved from Neotoma in several ways. Neotoma Explorer is a map-based interface designed for quick-look searches and first-pass data explorations. Explorer is well suited for researchers interested in quick-look searches and data views and for explorations by high school and college-level teachers and students. Teaching exercises using Neotoma Explorer have been prepared and hosted by the Science and Education Research Center (SERC) at Carleton College. An R package (neotoma) supports exporting of data from Neotoma into the R programmatic environment. [26] Application Programmatic Interfaces (APIs) support access to Neotoma data by third-party software developers. Resources using Neotoma data include the Flyover Country app for travelers and the Global Pollen Project.
Palynology is the study of microorganisms and microscopic fragments of mega-organisms that are composed of acid-resistant organic material and occur in sediments, sedimentary rocks, and even some metasedimentary rocks. Palynomorphs are the microscopic, acid-resistant organic remains and debris produced by a wide variety plants, animals, and Protista that have existed since the late Proterozoic.
Paleobotany, also spelled as palaeobotany, is the branch of botany dealing with the recovery and identification of plant remains from geological contexts, and their use for the biological reconstruction of past environments (paleogeography), and the evolutionary history of plants, with a bearing upon the evolution of life in general. A synonym is paleophytology. It is a component of paleontology and paleobiology. The prefix palaeo- or paleo- means "ancient, old", and is derived from the Greek adjective παλαιός, palaios. Paleobotany includes the study of terrestrial plant fossils, as well as the study of prehistoric marine photoautotrophs, such as photosynthetic algae, seaweeds or kelp. A closely related field is palynology, which is the study of fossilized and extant spores and pollen.
Paleoecology is the study of interactions between organisms and/or interactions between organisms and their environments across geologic timescales. As a discipline, paleoecology interacts with, depends on and informs a variety of fields including paleontology, ecology, climatology and biology.
Phytoliths are rigid, microscopic structures made of silica, found in some plant tissues and persisting after the decay of the plant. These plants take up silica from the soil, whereupon it is deposited within different intracellular and extracellular structures of the plant. Phytoliths come in varying shapes and sizes. Although some use "phytolith" to refer to all mineral secretions by plants, it more commonly refers to siliceous plant remains. In contrast, mineralized calcium secretions in cacti are composed of calcium oxalates.
During the Last Glacial Maximum, the mammoth steppe, also known as steppe-tundra, was once the Earth's most extensive biome. It stretched east-to-west, from the Iberian Peninsula in the west of Europe, across Eurasia to North America, through Beringia and Canada; from north-to-south, the steppe reached from the arctic islands southward to China. The mammoth steppe was cold and dry, and relatively featureless, though topography and geography varied considerably throughout. Some areas featured rivers which, through erosion, naturally created gorges, gulleys, or small glens. The continual glacial recession and advancement over millennia contributed more to the formation of larger valleys and different geographical features. Overall, however, the steppe is known to be flat and expansive grassland. The vegetation was dominated by palatable, high-productivity grasses, herbs and willow shrubs.
Paleolimnology is a scientific sub-discipline closely related to both limnology and paleoecology. Paleolimnological studies focus on reconstructing the past environments of inland waters using the geologic record, especially with regard to events such as climatic change, eutrophication, acidification, and internal ontogenic processes.
In paleoecology and ecological forecasting, a no-analog community or climate is one that is compositionally different from a baseline for measurement. Alternative naming conventions to describe no-analog communities and climates may include novel, emerging, mosaic, disharmonious and intermingled.
Picea critchfieldii is an extinct species of spruce tree formerly present on the landscape of North America, where it was once widely distributed throughout the southeastern United States. Plant macrofossil evidence reveals that this tree became extinct during the Late Quaternary period of Earth's history. At present, this is the only documented plant extinction from this geologic era. Hypotheses as to what specifically drove the extinction remain unresolved, but rapid and widespread climatic changes coincided with Picea critchfieldii's decline and ultimate extinction.
Margaret Bryan Davis is an American palynologist and paleoecologist, who used pollen data to study the vegetation history of the past 21,000 years. She showed conclusively that temperate- and boreal-forest species migrated at different rates and in different directions while forming a changing mosaic of communities. Early in her career, she challenged the standard methods and prevailing interpretations of the data and fostered rigorous analysis in palynology. As a leading figure in ecology and paleoecology, she served as president of the Ecological Society of America and the American Quaternary Association and as chair of the Department of Ecology, Evolution and Behavior at the University of Minnesota. In 1982 she was elected to the National Academy of Sciences and, in 1993, received the Eminent Ecologist Award from the Ecological Society of America.
Anna Katherine "Kay" Behrensmeyer is an American taphonomist and paleoecologist. She is a pioneer in the study of the fossil records of terrestrial ecosystems and engages in geological and paleontological field research into the ecological context of human evolution in East Africa. She is Curator of Vertebrate Paleontology in the Department of Paleobiology at the Smithsonian Institution's National Museum of Natural History (NMNH). At the museum, she is co-director of the Evolution of Terrestrial Ecosystems program and an associate of the Human Origins Program.
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms.
A glacial refugium is a geographic region which made possible the survival of flora and fauna during ice ages and allowed for post-glacial re-colonization. Different types of glacial refugia can be distinguished, namely nunatak, peripheral, and lowland. Glacial refugia have been suggested as a major cause of floral and faunal distribution patterns in both temperate and tropical latitudes. With respect to disjunct populations of modern-day species, especially in birds, doubt has been cast on the validity of such inferences, as much of the differentiation between populations observed today may have occurred before or after their restriction to refugia. In contrast, isolated geographic locales that host one or more critically endangered species are generally uncontested as bona fide glacial refugia.
Pyrogeography is the study of the past, present, and projected distribution of wildfire. Wildland fire occurs under certain conditions of climate, vegetation, topography, and sources of ignition, such that it has its own biogeography, or pattern in space and time. The earliest published evidence of the term appears to be in the mid-1990s, and the meaning was primarily related to mapping fires The current understanding of pyrogeography emerged in the 2000s as a combination of biogeography and fire ecology, facilitated by the availability of global-scale datasets of fire occurrence, vegetation cover, and climate. Pyrogeography has also been placed at the juncture of biology, the geophysical environment, and society and cultural influences on fire.
Changing climate conditions are amplified in polar regions and northern high-latitude areas are projected to warm at twice the rate of the global average. These modifications result in ecosystem interactions and feedbacks that can augment or mitigate climatic changes. These interactions may have been important through the large climate fluctuations since the glacial period. Therefore it is useful to review the past dynamics of vegetation and climate to place recent observed changes in the Arctic into context. This article focuses on northern Alaska where there has been much research on this theme.
Conservation paleobiology is a field of paleontology that applies the knowledge of the geological and paleoecological record to the conservation and restoration of biodiversity and ecosystem services. Despite the influence of paleontology on ecological sciences can be traced back at least at the 18th century, the current field has been established by the work of K.W. Flessa and G.P. Dietl in the first decade of the 21st century. The discipline utilizes paleontological and geological data to understand how biotas respond to climate and other natural and anthropogenic environmental change. These information are then used to address the challenges faced by modern conservation biology, like understanding the extinction risk of endangered species, providing baselines for restoration and modelling future scenarios for species range's contraction or expansion.
Cathy Lynn Whitlock is an American Earth Scientist and Professor at Montana State University. She is interested in Quaternary environmental change and palaeoclimatology and was a lead author of the 2017 Montana Climate Assessment. Whitlock has served as president of the American Quaternary Association and was elected to the National Academy of Sciences in 2018.
The wood-pasture hypothesis is a scientific hypothesis positing that open and semi-open pastures and wood-pastures formed the predominant type of landscape in post-glacial temperate Europe, rather than the common belief of primeval forests. The hypothesis proposes that such a landscape would be formed and maintained by large wild herbivores. Although others, including landscape ecologist Oliver Rackham, had previously expressed similar ideas, it was the Dutch researcher Frans Vera, who, in his 2000 book Grazing Ecology and Forest History, first developed a comprehensive framework for such ideas and formulated them into a theorem. Vera's proposals, although highly controversial, came at a time when the role grazers played in woodlands was increasingly being reconsidered, and are credited for ushering in a period of increased reassessment and interdisciplinary research in European conservation theory and practice. Although Vera largely focused his research on the European situation, his findings could also be applied to other temperate ecological regions worldwide, especially the broadleaved ones.
Sherilyn Fritz is known for her research on paleoclimate and paleoecology, with a particular focus on the use of diatoms to reconstruct past environmental conditions.
A rock hyrax midden is a stratified accumulation of fecal pellets and a brown amber-like a urinary product known as hyraceum excreted by the rock hyrax and closely related species.
Kitumbako Swamps is a small valley located near the Uluguru Mountains of Tanzania, and the site usually attracts paleoecological and archaeological investigations despite its inaccessibility to humans. Many scientific investigations done on this montane valley involve the assessment of biodiversity, fauna, sediments, vegetation, and fire activity to examine the possibility of human activity. Human activity, although not concrete, has been confirmed to be connected to this site as well as other montane grasslands in East Africa. However, the presence of humans in the past and present along with other environmental factors were explored to uncover current developments of the grasslands and gain a deeper understanding of their environmental resilience. Thus, much of the information that is gathered and published is from the results of off-site archaeology is paramount to understanding and learning about Kitumbako Swamps, especially since there is not enough information about excavations being executed on the site.