The fossil and geologic records provide the primary data used to established absolute timescales for timetrees. For the paleontological evaluation of proposed timetree timescales, and for node-based methods for constructing timetrees, the fossil record is used to bracket divergence times. Minimum brackets (minimum ages) can be established robustly using well-dated fossils that can be reliably assigned to lineages based on positive morphological evidence. Maximum brackets are much harder to establish, largely because it is difficult to establish definitive evidence that the absence of a taxon in the fossil record is real and not just due to the incompleteness of the fossil and rock records. Five primary methods have been developed to estimate maximum age brackets, each of which is discussed. The fact that the fossilization potential of a group typically decreases the closer one approaches its time of origin increases the challenge of estimating maximum age brackets. Additional complications arise: 1) because fossil data actually bracket the time of origin of the first relevant fossilizable morphology (apomorphy), not the divergence time itself; 2) due to the phylogenetic uncertainty in the placement of fossils; 3) because of idiosyncratic temporal and geographic gaps in the rock and fossil records; and 4) if the preservation potential of a group changed significantly during its history. In contrast, uncertainties in the absolute ages of fossils are typically relatively unimportant, even though the vast majority of fossil cannot be dated directly. These issues and relevant quantitative methods are reviewed, and their relative magnitudes assessed, which typically correlate with the age of the group, its geographic range, and species richness.

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Using the Fossil Record to Evaluate Timetree Timescales

Mapping paleocoastlines and continental flooding during the Phanerozoic

The fossil record of pinnipeds (seals, fur seals and walruses) is globally distributed, spanning from the late Oligocene to the Holocene. This record shows a complex evolutionary history that could...

https://royalsocietypublishing.org/doi/pdf/10.1098/rsos.191394

What do we know about the fossil record of pinnipeds? A historiographical investigation

Natural history collections are critical for modern scientific investigations, which are greatly expanding on the potential data applications of historic specimens. However, using these specimens outside their original intent introduces biases and potential misinterpretations. Anthropogenic biases can be introduced at any point during the life of museum specimens, from collection, preparation, and accession, to digitization. These biases can cause significant effects when the user is unaware of the collection context, as specific collection biases are often known anecdotally, but not ubiquitously. In this case study, the University of Kansas collection of Spence Shale Lagerstätte material was examined for anthropogenic biases using a collections inventory, interviews with stakeholders, and a literature review. Biases were found related to collector interest, locality preference, and researcher interest and specialization. These biases create a distorted view on the diversity and ecology of the Spence Shale, and need to be considered in future research. Anna F. Whitaker. Department of Chemical and Physical Sciences, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada. annawhitaker01@gmail.com Julien Kimmig. Earth and Mineral Sciences Museum & Art Gallery, Pennsylvania State University, University Park, Pennsylvania, 16802, USA. jkimmig@psu.edu

/pdf/anthropologically-introduced-biases-in-natural-history-1gojx2x2mh.pdf

Anthropologically introduced biases in natural history collections, with a case study on the invertebrate paleontology collections from the middle Cambrian Spence Shale Lagerstätte

How do scientists impact society in the twenty-first century? Many scientists are increasingly interested in the impact that their research will have on the public. Scientists likewise must answer the question above when applying for funding from government agencies, particularly as part of the 'Broader Impacts' criterion of proposals to the US National Science Foundation. This book equips scientists in all disciplines to do just that, by providing an overview of the origins, history, rationale, examples, and case studies of broader impacts, primarily drawn from the author's experiences over the past five decades. Beyond including theory and evidence, it serves as a 'how to' guide for best practices for scientists. Although this book primarily uses examples from the NSF, the themes and best practices are applicable to scientists and applications around the world where funding also requires impacts and activities that benefit society.

Broader Impacts of Science on Society

Large-scale analysis of the fossil record requires aggregation of palaeontological data from individual fossil localities Prior to computers, these synoptic datasets were compiled by hand, a laborious undertaking that took years of effort and forced palaeontologists to make difficult choices about what types of data to tabulate The advent of desktop computers ushered in palaeontology's first digital revolution-online literature-based databases, such as the Paleobiology Database (PBDB) However, the published literature represents only a small proportion of the palaeontological data housed in museum collections Although this issue has long been appreciated, the magnitude, and thus potential significance, of these so-called 'dark data' has been difficult to determine Here, in the early phases of a second digital revolution in palaeontology--the digitization of museum collections-we provide an estimate of the magnitude of palaeontology's dark data Digitization of our nine institutions' holdings of Cenozoic marine invertebrate collections from California, Oregon and Washington in the USA reveals that they represent 23 times the number of unique localities than are currently available in the PBDB These data, and the vast quantity of similarly untapped dark data in other museum collections, will, when digitally mobilized, enhance palaeontologists' ability to make inferences about the patterns and processes of past evolutionary and ecological changes

https://royalsocietypublishing.org/doi/pdf/10.1098/rsbl.2018.0431

K. A. Hollis

Papers

Quantifying the dark data in museum fossil collections as palaeontology undergoes a second digital revolution