Non-technical Summary

Paleontologists study the history of life on Earth, from its beginnings billions of years ago to the present day. To unify the discipline and develop a shared research agenda, nearly 200 scientists from more than 30 countries worked together to identify key questions for the future of paleontology. The resulting questions address topics including biodiversity, data integration, application of paleontology to societal issues, and utilizing new technology. Discussions also focus on topics related to improving the field, such as valuing specimen-based research, protecting fossil collecting sites, advocating for museums, and promoting diversity and inclusion among practitioners. These questions are a starting point for paleontologists for future developments of the discipline.

The Big Questions in Paleontology

The three solicitations for submission of Big Questions resulted in 528 contributed questions. (Supplementary Material 1: Raw Questions). The number of questions assigned to a given theme ranged from 14 to 76 (Table 2). Groups refined these questions (Supplementary Material 1: Preliminary Questions) to a preliminary list including 4 – 16 questions from each group (Table 2).

After feedback from all BQ participants, working groups again refined their questions, producing 5 – 10 final questions from each group (Table 2; Fig. 1). The BQs are available in Tables 3–13 (in non-ordered lists from each group), clustered in related themes, starting with questions pertaining to topics that might affect any paleontological study (e.g., preservation, scaling, taxonomy). In the eleven sections that follow, explanatory text accompanies the set of questions from each working group, with questions referred to in the text by working group acronyms (see section headers and tables for acronyms) and non-ordered, unranked numbering. Given the strong relationships among different areas of research in paleontology, there are overlaps in the topics of some questions, which can be taken to indicate important, cross-cutting themes within the discipline (Fig. 2).

The Adequacy of the Fossil Record (AFR; Table 3)

The fossil record is our primary window into the origin and evolution of life on Earth, providing the only direct line of evidence for these events. Yet, the fossil record is composed primarily of organisms with anatomical, behavioral, and ecological attributes that enhance their preservation potential (AFR1, Table 3; Kidwell and Flessa Reference Kidwell and Flessa1996; Behrensmeyer et al. Reference Behrensmeyer, Kidwell and Gastaldo2000; Sansom et al. Reference Sansom, Gabbott and Purnell2010; Klompmaker et al. Reference Klompmaker, Portell and Frick2017; Saleh et al. Reference Saleh, Antcliffe, Lefebvre, Pittet, Laibl, Peris, Lustri, Gueriau and Daley2020, Reference Saleh, Bath-Enright, Daley, Lefebvre, Pittet, Vite and Ma2021). Preservational biases are also often exacerbated by other biases introduced throughout the life of specimens (AFR2; e.g., Seilacher et al. Reference Seilacher, Reif and Westphal1985; Behrensmeyer et al. Reference Behrensmeyer, Kidwell and Gastaldo2000; Louys et al. Reference Louys, Kealy, O’Connor, Price, Hawkins, Aplin and Rizal2017; Krone et al. Reference Krone, Magoulick and Yohler2024)—for example, those relating to acquisition and curation, collecting, digitization, geography and geopolitics, publication, specimen preservation, storage, and transport (Flessa et al. Reference Flessa, Kowalewski and Walker1992; Whitaker and Kimmig Reference Whitaker and Kimmig2020; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022; Johnson et al. Reference Johnson and Owens2023). Methods development for evaluating and mitigating these biases continues to be an important area of research (AFR1–AFR3; e.g., Dunhill et al. Reference Dunhill, Hannisdal and Benton2014; Stewart et al. Reference Stewart, Carleton and Groucutt2021; De Baets et al. Reference De Baets, Jarochowska, Buchwald, Klug and Korn2022; Na et al. Reference Na, Li, Krause, Zhu and Kiessling2023; Antell et al. Reference Antell, Benson and Saupe2024; Hohmann et al. Reference Hohmann, Koelewijn, Burgess and Jarochowska2024). Adding to the challenge presented by these biases, maintenance of existing collections and capacity for new collections are threatened by a lack of funding, curatorial staff, and adequate storage facilities, both physical and digital (AFR3; Allmon et al. Reference Allmon, Dietl, Hendricks, Ross, Rosenberg and Clary2018; Marshall et al. Reference Marshall, Finnegan, Clites, Holroyd, Bonuso, Cortez and Davis2018).

Differences in data collection and reporting methods can compound biases in paleontological studies, as researchers have specific purposes when they acquire data (AFR4), and these idiosyncrasies can limit future uses of the data. To reduce duplication of data, reduce research costs, and increase versatility, it is imperative to document and clearly communicate data acquisition and management practices (e.g., as through the extended specimen concept; Lendemer et al. Reference Lendemer, Thiers, Monfils, Zaspel, Ellwood, Bentley and LeVan2020; Hardisty et al. Reference Hardisty, Ellwood, Nelson, Zimkus, Buschbom, Addink and Rabeler2022; Monfils et al. Reference Monfils, Krimmel, Linton, Marsico, Morris and Ruhfel2022). Establishing best practices in these areas will benefit paleontology as we move toward a “big data” future (i.e., data characterized by great variety, volume, and/or velocity; Balazka and Rodighiero Reference Balazka and Rodighiero2020), and digitization of existing and new specimens is becoming increasingly common (AFR2; Berents et al. Reference Berents, Hamer and Chavan2010; Allmon et al. Reference Allmon, Dietl, Hendricks, Ross, Rosenberg and Clary2018).

Methodological, imaging, and analytical advances—geochemical approaches in particular (e.g., nontraditional stable isotopes, synchrotron, handheld XRF)—have created new opportunities for evaluating preservational processes (e.g., Gueriau et al. Reference Gueriau, Bernard and Bertrand2016; Teng et al. Reference Teng, Dauphas and Watkins2017). For example, advances in organic geochemistry have increased the capacity to extract biomolecules and biomarkers from fossil and sedimentary archives (e.g., Schweitzer et al. Reference Schweitzer, Avci, Collier and Goodwin2008; Briggs and Summons Reference Briggs and Summons2014; Vinther Reference Vinther2015; Falk and Wolkenstein Reference Falk and Wolkenstein2017; Demarchi Reference Demarchi2020; Wiemann et al. Reference Wiemann, Crawford and Briggs2020; McNamara et al. Reference McNamara, Rossi, Slater, Rogers, Ducrest, Dubey and Roulin2021). However, it remains to be seen how deep in time biomolecules can be found and with what accuracy and resolution the methods can be applied through geological time (AFR5). Inorganic geochemistry has also advanced fundamentally in the last decades, as stable isotope (traditional and nontraditional) and clumped isotope systems provide new insights in studies of pCO₂, pH, paleophysiology, mass extinctions, and the paleobiology and paleoenvironment of fossil taxa (e.g., Casey and Post Reference Casey and Post2011; Cook et al. Reference Cook, Languille, Dufour, Mocuta, Tombret, Fortuna and Bertrand2015; Kimmig and Holmden Reference Kimmig and Holmden2017; Martin et al. Reference Martin, Tacail and Balter2017; Chen et al. Reference Chen, Montañez, Qi, Shen and Wang2018; Kral et al. Reference Kral, Lagos, Guagliardo, Tütken and Geisler2022; Jung et al., Reference Jung, Zoppe, Söte, Moretti, Duprey, Foreman and Wald2024). Geochemical advances and continuing improvements to technology and equipment also are expanding the scope of paleontology by enhancing our understanding of diagenesis, morphology, paleoecology, and paleoclimate (AFR6, AFR7; e.g., Smith et al. Reference Smith, Bevitt, Zaim, Rizal, Aswan and Trihascaryo2021; Abdelhady et al. Reference Abdelhady, Seuss, Jain, Abdel-Raheem, Elsheikh, Ahmed, Elewa and Hussain2024; Comans et al. Reference Comans, Smart, Kast, Lu, Lüdecke, Leichliter, Sigman, Ikejiri and Martínez‐García2024).

The changing global environment also presents new challenges and opportunities for sampling the fossil record (AFR8). For example, as sea level rises and extreme weather events become more common, some existing fossil collecting sites along the coasts may be submerged (e.g., chalk deposits in Europe), while the same processes might lead to the exposure of new sites (e.g., Reimann et al. Reference Reimann, Vafeidis, Brown, Hinkel and Tol2018; Vousdoukas et al. Reference Vousdoukas, Clarke, Ranasinghe, Reimann, Khalaf, Duong and Ouweneel2022). It is also likely that rising temperatures causing the loss of permafrost and glacial ice will expose previously inaccessible outcrops that offer new opportunities for research, even as the changing climate alters erosional processes that may influence fossil exposure and quality (AFR8; e.g., Clark et al. Reference Clark, Bayarsaikhan, Miller, Vanderwarf, Hart, Caspari and Taylor2021).

Scaling Ecological and Evolutionary Processes and Patterns (SEP; Table 4)

The scale of an investigation influences the observation and interpretation of ecological and evolutionary processes (SEP1–SEP4, Table 4). In paleontology, scale often relates to the temporal and spatial dimensions of taxa, patterns, or processes (SEP2, SEP3). Ecological and evolutionary processes occur at multiple spatiotemporal scales, but identifying or demonstrating their significance at all scales is challenging and rare (SEP4; Jablonski Reference Jablonski2008; Price and Schmitz Reference Price and Schmitz2016; Rapacciuolo and Blois Reference Rapacciuolo and Blois2019; Louys et al. Reference Louys, Price and Travouillon2021; Liow et al. Reference Liow, Uyeda and Hunt2023). Evaluating the effects of scaling in the fossil record is further complicated by the need to identify and address the incompleteness of the record (SEP3, SEP5; Peters and Heim Reference Peters and Heim2011; Benson et al. Reference Benson, Butler, Close, Saupe and Rabosky2021; and see “The Adequacy of the Fossil Record”). The data captured in the fossil record are imperfect and biased, providing only a glimpse of longer and shorter processes, patterns, and interactions (SEP3, SEP5–SEP7; Faith et al. Reference Faith, Du, Behrensmeyer, Davies, Patterson, Rowan and Wood2021; Flannery-Sutherland et al. Reference Flannery-Sutherland, Silvestro and Benton2022; Dunne et al. Reference Dunne, Thompson, Butler, Rosindell and Close2023).

Table 4.

Big Questions for the working group on “Scaling Ecological and Evolutionary Processes and Patterns”

Paleontological research into the ecological and evolutionary drivers of observed patterns is flourishing, as emergent research areas—for example, conservation paleobiology (Dietl et al. Reference Dietl, Kidwell, Brenner, Burney, Flessa, Jackson and Koch2015; Dillon et al. Reference Dillon, Pier, Smith, Raja, Dimitrijević, Austin and Cybulski2022), geobiology (Knoll et al. Reference Knoll, Canfield and Konhauser2012), and phylogenetic paleoecology (Lamsdell et al. Reference Lamsdell, Congreve, Hopkins, Krug and Patzkowsky2017)—bridge subdisciplines and broach connections between the micro- and macroevolutionary scales (SEP2, SEP5 – 7; e.g., Machado et al. Reference Machado, Mongle, Slater, Penna, Wisniewski, Soffin, Dutra and Uyeda2023; Rolland et al. Reference Rolland, Henao-Diaz, Doebeli, Germain, Harmon, Knowles, Liow, Mank, Machac and Otto2023). Paleontologists must grapple with demonstrating links to the biology of modern organisms (i.e., neontology) in studies at various scales in the fossil record (Dietl et al. Reference Dietl, Smith and Durham2019; Rapacciuolo and Blois Reference Rapacciuolo and Blois2019). Unifying paleo- and neontological data can reveal more about the natural world than either could in isolation (e.g., Hlusko et al. Reference Hlusko, Schmitt, Monson, Brasil and Mahaney2016; Smith et al. Reference Smith, Rillo, Kocsis, Dornelas, Fastovich, Huang and Jonkers2023c); however, the efficacy of cross-scale analyses needs continued examination. Macroecology (Brown Reference Brown1995; McGill Reference McGill2019) may provide one option to incorporate a conceptual basis for this work as, for example, studies of the metacommunity concept—a set of local communities that are linked by dispersal of multiple, potentially interacting species (Leibold et al. Reference Leibold, Holyoak, Mouquet, Amarasekare, Chase, Hoopes and Holt2004)—provide a framework for examining scale-based problems. A tenet of this concept is that the study of local patterns and processes is not sufficient to understand the structure and dynamics of a metacommunity (Leibold et al. Reference Leibold, Holyoak, Mouquet, Amarasekare, Chase, Hoopes and Holt2004). Studying metacommunity composition and community assembly over space and time acknowledges the fluidity and connection of communities and seeks common patterns across metacommunities (SEP6; e.g., Muscente et al. Reference Muscente, Prabhu, Zhong, Eleish, Meyer, Fox, Hazen and Knoll2018, Reference Muscente, Martindale, Prabhu, Ma, Fox, Hazen and Knoll2022; Eden et al. Reference Eden, Manica and Mitchell2022; Gibert et al. Reference Gibert, Zacaï, Fluteau, Ramstein, Chavasseau, Thiery and Souron2022). The relationship between the processes on evolutionary scales, their relative influence, and fluctuations through time continue to be important topics (SEP2, SEP4, SEP8).

Over the course of Earth’s history, the biosphere has had a profound impact on the geosphere in ways that we are still working to fully comprehend (SEP9). Studying the interaction from an abiotic perspective highlights the feedback mechanisms and interactions within the Earth–life system, as traces of life are ubiquitous from Earth’s mantle to the atmosphere (Pawlik et al. Reference Pawlik, Buma, Šamonil, Kvaček, Galązka, Kohout and Malik2020; Giuliani et al. Reference Giuliani, Drysdale, Woodhead, Planavsky, Phillips, Hergt, Griffin, Oesch, Dalton and Davies2022).

Phylogenetics, Taxonomy, and Systematics (PTS; Table 5)

The fossil record contains unique information on the diversity of previous life-forms and their relationships to one another, which provides retrospective context for cataloging and understanding life on the planet today. Phylogenetics is often perceived simply as a tool for inferring evolutionary relationships or organizing biodiversity but also can be seen more broadly as a framework for hypothesis testing and reconstructing past events that are not directly observable in the fossil record (Bromham Reference Bromham2016). This can include estimating species divergence times, studying trait evolution, or quantifying diversification dynamics. Although speciation and extinction have a long history of study, these processes are complex, and some aspects require further study to improve our understanding (PTS1, PTS2, Table 5). By adopting new methodologies, improving data collection practices, and integrating various types of data centered around current, carefully constructed taxonomies, we can unlock the full potential of hypothesis testing using phylogenetic approaches (PTS3).

Table 5.

Big Questions for the working group on “Phylogenetics, Taxonomy, and Systematics”

Phylogenies are often constructed using molecular data, but there are many benefits to including information from other sources, such as the fossil record (PTS4, PTS5; Parham et al. Reference Parham, Donoghue, Bell, Calway, Head, Holroyd and Inoue2012; Lee and Palci Reference Lee and Palci2015; Mongiardino Koch et al. Reference Mongiardino Koch, Garwood and Parry2021; Wright et al. Reference Wright, Bapst, Barido-Sottani and Warnock2022). Other data sources, such as developmental biology (Wright Reference Wright2015), may also prove useful in phylogenetic inference (PTS6). The field requires a multidisciplinary perspective informed by computer and data science, ecology, geology, geochronology, phylogenomics, and statistics (Parham et al. Reference Parham, Donoghue, Bell, Calway, Head, Holroyd and Inoue2012; Liow et al. Reference Liow, Uyeda and Hunt2023). Phylogenomics and deep learning can help to discern and organize biodiversity, but their accuracy will always depend on the quality of their input data, which necessitates reliable systematics and taxonomic identifications (e.g., Bortolus Reference Bortolus2008). The accuracy of phylogenetic analyses that include fossils relies on information about taxonomies and their associated uncertainties (Bortolus Reference Bortolus2008; Parham et al. Reference Parham, Donoghue, Bell, Calway, Head, Holroyd and Inoue2012; Soul and Friedman Reference Soul and Friedman2015; Barido-Sottani et al. Reference Barido-Sottani, Pohle, De Baets, Murdock and Warnock2023). Taxonomy and comparative anatomy are invaluable in understanding diversification history and character evolution, establishing homologies, quantifying variability, and generating testable hypotheses using phylogenetics and species delimitation methods (Barido-Sottani et al. Reference Barido-Sottani, Pohle, De Baets, Murdock and Warnock2023). These research fields must be supported in their own right (Agnarsson and Kuntner Reference Agnarsson and Kuntner2007; Löbl et al. Reference Löbl, Klausnitzer, Hartmann and Krell2023; Smith et al. Reference Smith, Raja, Clements, Dimitrijević, Dowding, Dunne and Gee2023b).

Integrating different data types requires explicit process-based models (PTS7, PTS8), such as the fossilized birth–death model, which models speciation, extinction, and fossilization simultaneously (Stadler Reference Stadler2010; Heath et al. Reference Heath, Huelsenbeck and Stadler2014). Combined with models of molecular and morphological evolution, this framework allows for statistical inference of dated phylogenies that include extant and fossil taxa. Most existing models treat speciation and character evolution as independent (Warnock and Wright Reference Warnock and Wright2020), but further refinement of this framework can illuminate the tempo and mechanisms of speciation (PTS1). Comprehensive analyses also require approaches that capture uncertainty and biases while concurrently allowing for varied approaches to weighting of molecular and morphological data (PTS9). We can construct explicit Bayesian hierarchical models to incorporate different data types while accounting for uncertainty in a principled and intuitive way (e.g., Höhna et al. Reference Höhna, Landis, Heath, Boussau, Lartillot, Moore, Huelsenbeck and Ronquist2016; Bouckaert et al. Reference Bouckaert, Vaughan, Barido-Sottani, Duchêne, Fourment, Gavryushkina and Heled2019; Ronquist et al. Reference Ronquist, Kudlicka, Senderov, Borgström, Lartillot, Lundén, Murray, Schön and Broman2021). It is also imperative to assess the trade-off between data availability, computational efficiency, and model complexity. Simulations play an important role in confronting this challenge and parameter identifiability issues associated with phylogenetic models by helping to explore the performance of available methods, potential limitations of data, and the expectations under null hypotheses (Barido-Sottani et al. Reference Barido-Sottani, Pett, O’Reilly and Warnock2019; Louca and Pennell Reference Louca and Pennell2020; Höhna et al. Reference Höhna, Kopperud and Magee2022; Mulvey et al. Reference Mulvey, May, Brown, Höhna, Wright and Warnock2024).

Environmental and geological processes influence the course of evolution (e.g., Arakaki et al. Reference Arakaki, Christin, Nyffeler, Lendel, Eggli, Ogburn, Spriggs, Moore and Edwards2011; Hannisdal and Peters Reference Hannisdal and Peters2011; De Baets et al. Reference De Baets, Antonelli and Donoghue2016; Kocsis et al. Reference Kocsis, Reddin, Scotese, Valdes and Kiessling2021). Incorporating these processes into phylogenetics will elucidate their interaction with biological events, linking large-scale processes, such as the extent and timing of climatic change, continental breakup, or changes in depositional rates through time with evolutionary phenomena (PTS10).

Biodiversity Dynamics in Space and Time (BST; Table 6)

Quantifying and interpreting biodiversity dynamics over time is a long-standing theme in paleontology (Phillips Reference Phillips1860; Sepkoski et al. Reference Sepkoski, Bambach, Raup and Valentine1981; Benson et al. Reference Benson, Butler, Close, Saupe and Rabosky2021), leading to questions such as whether there are constraints on global biodiversity (BST1, Table 6; Alroy et al. Reference Alroy, Aberhan, Bottjer, Foote, Fürsich, Harries and Hendy2008; Harmon and Harrison Reference Harmon and Harrison2015; Rabosky and Hurlbert Reference Rabosky and Hurlbert2015; Close et al. Reference Close, Benson, Saupe, Clapham and Butler2020). Given the challenge of fully documenting modern biodiversity (Mora et al. Reference Mora, Tittensor, Adl, Simpson and Worm2011), we cannot expect to know absolute biodiversity in the past, but we can estimate relative changes in biodiversity. Genuine trajectories of biodiversity through time can be uncovered only if we can account for spatial differences and temporal changes in preservation potential, as well as other biases particular to the fossil record (e.g., Smiley Reference Smiley2018; Krone et al. Reference Krone, Magoulick and Yohler2024; and see “The Adequacy of the Fossil Record”). By dissecting the components of these trajectories, we can identify drivers of originations and extinctions in deep time (BST5; and see “Adaptations, Innovations, Origins”). To fully understand biodiversity, we must first agree on the most effective methods for measuring biodiversity over different timescales (BST6; see “Scaling Ecological and Evolutionary Processes and Patterns”). Such a consensus can help address pressing questions, including whether modern biodiversity is an outlier in geological time (BST7).

Table 6.

Big Questions for the working group on “Biodiversity Dynamics in Space and Time”

Spatial aspects of biodiversity, such as the latitudinal diversity gradient (Humboldt Reference Humboldt1808), are as important as temporal patterns. An extensive literature explores causes of the latitudinal diversity gradient, including its dynamics over geological timescales (Jablonski et al. Reference Jablonski, Roy and Valentine2006; Allen et al. Reference Allen, Wignall, Hill, Saupe and Dunhill2020, Reference Allen, Clapham, Saupe, Wignall, Hill and Dunhill2023; Zacaï et al. Reference Zacaï, Monnet, Pohl, Beaugrand, Mullins, Kroeck and Servais2021; Fenton et al. Reference Fenton, Aze, Farnsworth, Valdes and Saupe2023; Quintero et al. Reference Quintero, Landis, Jetz and Morlon2023). Evidence points to a close link between the intensity of the latitudinal diversity gradient and paleoclimate (Mannion et al. Reference Mannion, Upchurch, Benson and Goswami2014; Yasuhara et al. Reference Yasuhara, Wei, Kucera, Costello, Tittensor, Kiessling and Bonebrake2020; Yasuhara and Deutsch Reference Yasuhara and Deutsch2022), but exactly how the latitudinal diversity gradient changed over time remains an open question (BST2).

Biodiversity patterns are the result of extinctions, originations, and the intricate interactions between living organisms and their environment. Identifying the specific factors that drive global changes in biodiversity and disentangling the individual and combined effects of these factors require careful research and analysis (BST3; and see “Biodiversity Drivers”). Approaches leveraging new tools—including mechanistic models (e.g., Saupe et al. Reference Saupe, Myers, Peterson, Soberón, Singarayer, Valdes and Qiao2019), machine learning (e.g., Raja et al. Reference Raja, Lauchstedt, Pandolfi, Kim, Budd and Kiessling2021), and network analysis (e.g., Muscente et al. Reference Muscente, Prabhu, Zhong, Eleish, Meyer, Fox, Hazen and Knoll2018, Reference Muscente, Martindale, Prabhu, Ma, Fox, Hazen and Knoll2022; Woodhouse et al. Reference Woodhouse, Swain, Fagan, Fraass and Lowery2023)—can identify key drivers of global and regional biodiversity and biodiversity hotspots through time (Cermeño et al. Reference Cermeño, García-Comas, Pohl, Williams, Benton, Chaudhary and Le Gland2022) or at least provide testable hypotheses. We are only beginning to understand and quantify the role of biodiversity as a driver of ecosystem function in the paleontological record (BST4), underscoring the need for consistent units of measure across spatiotemporal scales (BST6; McGuire et al. Reference McGuire, Lawing, Díaz and Stenseth2023).

Biodiversity Drivers (BD; Table 7)

In paleontology, documenting patterns of biodiversity is a central theme, but understanding the factors that drive these patterns is a large task (Jablonski Reference Jablonski2008, Reference Jablonski2017; Ezard et al. Reference Ezard, Quental and Benton2016; Di Martino et al. Reference Di Martino, Jackson, Taylor and Johnson2018). We can, however, begin to address this challenge by decomposing the task into more manageable questions and hypotheses that extend across taxonomic levels. Comparing taxa with differing ecological characteristics (BD1, Table 7) may help disentangle prevailing drivers—including anthropogenic drivers—under shared and disparate environmental conditions or times of perturbation (BD2; Harnik Reference Harnik2011; Klompmaker et al. Reference Klompmaker, Schweitzer, Feldmann and Kowalewski2013; Hull et al. Reference Hull, Darroch and Erwin2015; Trubovitz et al. Reference Trubovitz, Renaudie, Lazarus and Noble2023). To compare the potential drivers across taxonomic groups and to do so on different spatial and temporal scales, it is crucial to standardize, harmonize, and clearly communicate study design and methods (Hayek et al. Reference Hayek, Buzas and Thomas2019). Doing so will help us establish broader principles that transcend specific taxonomic, spatial, and temporal contexts (BD3).

Table 7.

Big Questions for the working group on “Biodiversity Drivers”

Abiotic and biotic conditions change through time at varying rates and magnitudes, and their effects on biodiversity and ecosystem dynamics warrant further study (BD4, BD7). It has been suggested that abiotic drivers act over broad spatiotemporal scales (e.g., Court Jester model; Barnosky Reference Barnosky2001), whereas biotic drivers are more applicable on local and shorter scales (e.g., Red Queen model; Benton Reference Benton2009; Vermeij and Roopnarine Reference Vermeij and Roopnarine2013; Wisz et al. Reference Wisz, Pottier, Kissling, Pellissier, Lenoir, Damgaard and Dormann2013). The relative significance of these sets of drivers remains uncertain (BD6; e.g., Eichenseer et al. Reference Eichenseer, Balthasar, Smart, Stander, Haaga and Kiessling2019; Bush and Payne Reference Bush and Payne2021; Spiridonov and Lovejoy Reference Spiridonov and Lovejoy2022), underscoring the importance of conceptual models for how biodiversity responds to them (Vrba Reference Vrba1985, Reference Vrba1992, Reference Vrba1993; Mancuso et al. Reference Mancuso, Irmis, Pedernera, Gaetano, Benavente and Breeden2022). There is evidence that diversification patterns observed at higher taxonomic levels (e.g., family) are not always replicated at lower levels (e.g., species; Jablonski Reference Jablonski2007; Hendricks et al. Reference Hendricks, Saupe, Myers, Hermsen and Allmon2014; Balisi and Van Valkenburgh Reference Balisi and Van Valkenburgh2020). Across each of these variables, the effects of scale on which hypothesis is supported (i.e., biotic or abiotic drivers) merit further consideration—in some instances, relationships may be reversed when comparing shorter ecological and longer evolutionary timescales (BD3; e.g., De Baets et al. Reference De Baets, Huntley, Scarponi, Klompmaker and Skawina2021). Further exploration with differing spatiotemporal scales, taxonomic groups, and ecologies is needed, as it remains a challenge to dissect the complex interplay between ecology, microevolution, and macroevolution on geological timescales (BD8, BD9; e.g., Liow and Taylor Reference Liow and Taylor2019; Liow et al. Reference Liow, Uyeda and Hunt2023). Examining the reciprocal effects of biological evolution as an actor, as well as in feedbacks and as a primary driver in other Earth systems, is a promising research direction (BD5).

Adaptations, Innovations, Origins (AIO; Table 8)

The evolutionary history of many species (and higher taxa) is demarcated by adaptive novelties and innovations along with repeated migration, dispersal, and colonization events as species have evolved and survived through morphological adaptation, ontogenetic shifts, and novel behaviors (AIO1, Table 8; e.g., Nylin et al. Reference Nylin, Agosta, Bensch, Boeger, Braga, Brooks and Forister2018; Stigall Reference Stigall2019). Colonizing regions in new environments and adapting to cope with the challenges induced by new environmental pressures has led to the development and emergence of advantageous novelties over time. These novelties increase the capacity of individuals to survive, thrive, and reproduce (AIO1, AIO2; e.g., Patton et al. Reference Patton, Harmon, del Rosario Castañeda, Frank, Donihue, Herrel and Losos2021; Tihelka et al. Reference Tihelka, Howard, Cai and Lozano-Fernandez2022; Woehle et al. Reference Woehle, Roy, Glock, Michels, Wein, Weissenbach and Romero2022). Observing modern species and their responses to stimuli provides paleontologists with a means to connect microevolutionary processes and patterns to those observed over evolutionary timescales in the fossil record (AIO6), which are obscured by taphonomic processes (AIO3). Improving data integration across scales, leveraging new methods, and better accounting for biases can help us answer long-standing questions on topics relating to phylogenomic conflict (Parins-Fukuchi et al. Reference Parins-Fukuchi, Stull and Smith2021), evolutionary patterns (e.g., phyletic gradualism vs. punctuated equilibrium; Gould and Eldredge Reference Gould and Eldredge1972; Hunt Reference Hunt2007; Hunt et al. Reference Hunt, Hopkins and Lidgard2015; Tsuboi et al. Reference Tsuboi, Sztepanacz, De Lisle, Voje, Grabowski, Hopkins and Porto2024), and phylogenetic relationships (Wright et al. Reference Wright, Bapst, Barido-Sottani and Warnock2022).

Table 8.

Big Questions for the working group on “Adaptations, Innovations, Origins”

The interdependence among ecological determinants and biological features requires thorough examination to reveal the inextricable relationship between micro- and macroevolutionary processes, environmental change, and preservation (AIO4–AIO6; e.g., Lamsdell et al. Reference Lamsdell, McCoy, Perron-Feller and Hopkins2020; Almécija et al. Reference Almécija, Hammond, Thompson, Pugh, Moyà-Solà and Alba2021; and see “The Adequacy of the Fossil Record”). To develop these research directions (AIO5–AIO7), hypotheses on the emergence of major features (e.g., Naranjo-Ortiz and Gabaldón Reference Naranjo-Ortiz and Gabaldón2019; Murdock Reference Murdock2020), changes in morphology (e.g., Anderson and Ruxton Reference Anderson and Ruxton2020; Hopkins and To Reference Hopkins and To2022), ontogeny (e.g., Chevalier et al. Reference Chevalier, Colard, Colombo, Golovanova, Doronichev and Hublin2021; Friend et al. Reference Friend, Anderson and Allmon2021; Lanzetti et al. Reference Lanzetti, Portela-Miguez, Fernandez and Goswami2022), and behavior (e.g., Berbee et al. Reference Berbee, Strullu-Derrien, Delaux, Strother, Kenrick, Selosse and Taylor2020; Yamamoto and Caterino Reference Yamamoto and Caterino2023) require contextualization with spatiotemporal, taphonomic, and preservational constraints (AIO3, AIO4). Answering these questions can facilitate the examination of overarching patterns in biotic developmental and community responses to perturbation throughout the history of life and can possibly be projected to the future (AIO6). Studies on the emergence of adaptations, innovative features, ontogenetic strategies, behaviors, and the development of novelties can provide paleontology with crucial insights into the processes of evolution and extinction, as well as the interactions between individuals, species, and communities (AIO5–AIO7; Barido-Sottani et al. Reference Barido-Sottani, Van Tiel, Hopkins, Wright, Stadler and Warnock2020; Brocklehurst and Benson Reference Brocklehurst and Benson2021; Stansfield et al. Reference Stansfield, Mitteroecker, Vasilyev, Vasilyev and Butaric2021; Dunhill et al. Reference Dunhill, Zarzyczny, Shaw, Atkinson, Little and Beckerman2024).

Extinction Dynamics (ED; Table 9)

The understanding that species are ephemeral and will eventually become extinct is now a fundamental principle of paleontology (Cuvier Reference Cuvier1813; Darwin Reference Darwin1859; MacLeod Reference MacLeod2014; Marshall Reference Marshall2017)—and potentially scales up from species to faunas and paleocommunities (e.g., Muscente et al. Reference Muscente, Martindale, Prabhu, Ma, Fox, Hazen and Knoll2022). This concept is integral to the study of the history of life on Earth, as it helps to explain changes in biodiversity observed in the fossil record (Jablonski Reference Jablonski1991; McKinney Reference McKinney1997). At the same time, extinction is a major theme in modern bioscience relating to impacts of anthropogenic stressors (e.g., climate change, habitat change, pollution; McKinney Reference McKinney1997; Dirzo et al. Reference Dirzo, Young, Galetti, Ceballos, Isaac and Collen2014). As is usual for comparisons of the modern and fossil records, attempting to bridge the differences in study characteristics (e.g., evolutionary history of ecosystems; spatiotemporal completeness, extent, and resolution; taxonomic completeness; Foote Reference Foote2000; Eichenseer et al. Reference Eichenseer, Balthasar, Smart, Stander, Haaga and Kiessling2019; Foster et al. Reference Foster, Allen, Kitzmann, Münchmeyer, Rettelbach, Witts and Whittle2023; Pohl et al. Reference Pohl, Stockey, Dai, Yohler, Le Hir, Hülse, Brayard, Finnegan and Ridgwell2023; Finnegan et al. Reference Finnegan, Harnik, Lockwood, Lotze, McClenachan and Kahanamoku2024) over which extinction can be observed necessitates reflection on which data types are suitable to facilitate cross-scale studies and comparisons (ED1, Table 9; Lotze et al. Reference Lotze, Erlandson, Hardt, Norris, Roy, Smith, Whitcraft, Jackson, Alexander and Sala2011; Andréoletti and Morlon Reference Andréoletti, Morlon and Scheiner2024).

Table 9.

Big questions for the working group on “Extinction Dynamics”

The “BigFive” mass extinctions originally were defined using the concept of statistical outliers (Raup and Sepkoski Reference Raup and Sepkoski1982) at a high taxonomic level, using a specific rate metric, and based on skeletonized marine organisms. An updated definition of mass extinction is long overdue, as is a dialogue on how pattern and process should be included in the definition (ED2; Marshall Reference Marshall2023). This definition would precipitate the reexamination of whether mass extinctions are associated with consistent vulnerabilities of specific morphological and ecological traits (ED3, ED4; Foster et al. Reference Foster, Allen, Kitzmann, Münchmeyer, Rettelbach, Witts and Whittle2023) and whether their phases and recovery patterns are comparable (ED6, ED7; Hull et al. Reference Hull, Darroch and Erwin2015).

Another aspect of extinction dynamics, pertaining to the ecological impact of the event, is whether functional diversity is maintained across mass extinction events (ED5; Bambach et al. Reference Bambach, Bush and Erwin2007; Foster and Twitchett Reference Foster and Twitchett2014; Aberhan and Kiessling Reference Aberhan and Kiessling2015; Dunhill et al. Reference Dunhill, Foster, Sciberras and Twitchett2018; Muscente et al. Reference Muscente, Prabhu, Zhong, Eleish, Meyer, Fox, Hazen and Knoll2018; Cribb et al. Reference Cribb, Formoso, Woolley, Beech, Brophy, Byrne and Cassady2023). Mass extinctions are often attributed to abiotic changes (e.g., changes in temperature, oxygen content, pH), and finding thresholds relating to magnitudes and rates of such changes remains a priority (ED8; Song et al. Reference Song, Kemp, Tian, Chu, Song and Dai2021). Species also are likely to experience secondary extinction cascades due to the loss of critical biotic interactions (e.g., predator–prey relationships) in trophic or other biological interaction networks (Roopnarine Reference Roopnarine2006; Dunne and Williams Reference Dunne and Williams2009). If we are to truly understand the dynamics of extinction events in the fossil record and use them to predict extinction risk in our human-dominated world (Barnosky et al. Reference Barnosky, Matzke, Tomiya, Wogan, Swartz, Quental and Marshall2011; Braje and Erlandson Reference Braje and Erlandson2013; Song et al. Reference Song, Kemp, Tian, Chu, Song and Dai2021; Vahdati et al. Reference Vahdati, Weissmann, Timmermann, de León and Zollikofer2022), we need to understand the interplay between primary and secondary extinction events via the inclusion of biotic interactions in studies of extinction selectivity (e.g., Sanders et al. Reference Sanders, Thébault, Kehoe and van Veen2018; Mulvey et al. Reference Mulvey, Warnock and De Baets2022; Dunhill et al. Reference Dunhill, Zarzyczny, Shaw, Atkinson, Little and Beckerman2024).

Climate Change Past and Present (CPP; Table 10)

Paleontologists often reconstruct past climates using fossils or geochemical proxies, and this remains a major theme in the biogeosciences (CPP1, Table 10). For example, examining stable oxygen isotopes in fossils can reveal climate change across temporal scales, from the life span of individual organisms (e.g., Nützel et al. Reference Nützel, Joachimski and Correa2010; Alberti et al. Reference Alberti, Fürsich and Pandey2013) to the eon scale (e.g., Song et al. Reference Song, Wignall, Song, Dai and Chu2019; Grossman and Joachimski Reference Grossman and Joachimski2022). However, smoothly integrating data across these temporal scales remains challenging (CPP1). Assessing biotic responses to changing climates is becoming a major theme in paleontology, with several pertinent questions (CPP2–CPP9; e.g., Rita et al. Reference Rita, Nätscher, Duarte, Weis and De Baets2019; Piazza et al. Reference Piazza, Ullmann and Aberhan2020; Nätscher et al. Reference Nätscher, Gliwa, De Baets, Ghaderi and Korn2023). Nevertheless, it is critical to avoid circular reasoning where climate reconstructions based on fossil proxies subsequently are used to interpret fossils.

Table 10.

Big Questions for the working group on “Climate Change Past and Present”

A host of variables—including direct and indirect measures of nutrient levels, temperature, pCO₂, precipitation, salinity, pH, and, oxygen and other isotopes—can be used to examine the influence of climate on biodiversity (Bijma et al. Reference Bijma, Pörtner, Yesson and Rogers2013; Saupe et al. Reference Saupe, Myers, Peterson, Soberón, Singarayer, Valdes and Qiao2019; Jane et al. Reference Jane, Hansen, Kraemer, Leavitt, Mincer, North and Pilla2021; Jackson and O’Dea Reference Jackson and O’Dea2023; Lin et al. Reference Lin, Wei, Ho and Lo2023; Yasuhara and Deutsch Reference Yasuhara and Deutsch2023; Malanoski et al. Reference Malanoski, Farnsworth, Lunt, Valdes and Saupe2024). Elucidating the relative importance of these variables on biodiversity can guide conservation efforts (CPP2, CPP8), although best practices for bridging the mismatch in temporal scales studied in paleontology and those of interest to policymakers remain elusive (CPP3; Smith et al. Reference Smith, Durham, Dietl, Tyler and Schneider2018; Pimiento and Antonelli Reference Pimiento and Antonelli2022; Groff et al. Reference Groff, MacKenzie, Pier, Shaffer and Dietl2023; Kiessling et al. Reference Kiessling, Smith and Raja2023; and see “Scaling Ecological and Evolutionary Processes and Patterns”). Bridging these gaps can benefit from studies leveraging conservatism of physiology (Reddin et al. Reference Reddin, Nätscher, Kocsis, Pörtner and Kiessling2020), simulations (e.g., Hunt Reference Hunt2012; Barido-Sottani et al. Reference Barido-Sottani, Pett, O’Reilly and Warnock2019; Raja et al. Reference Raja, Lauchstedt, Pandolfi, Kim, Budd and Kiessling2021; Smith et al. Reference Smith, Pruden, Handley, Durham and Dietl2023a), and the pursuit of higher-resolution paleontological datasets (Smith et al. Reference Smith, Rillo, Kocsis, Dornelas, Fastovich, Huang and Jonkers2023c). The application of paleontological observations to conservation practice remains primarily aspirational (Groff et al. Reference Groff, MacKenzie, Pier, Shaffer and Dietl2023); however, leveraging the need for temporal context to understand climate change is a promising avenue for integrating paleontological data (Smith et al. Reference Smith, Durham, Dietl, Tyler and Schneider2018; Dietl et al. Reference Dietl, Smith and Durham2019; Kiessling et al. Reference Kiessling, Raja, Roden, Turvey and Saupe2019, Reference Kiessling, Smith and Raja2023).

Climate sensitivity has been defined as the global mean temperature increase when atmospheric CO₂ equivalent concentration is doubled (IPCC Reference Masson-Delmotte, Zhai, Pirani, Connors, Péan, Berger and Caud2021), and we can use this framework to define “ecosystem sensitivity” (CPP4). For example, how much will ecological structure—a concept challenging to objectively measure (e.g., Parrott Reference Parrott2010; LaRue et al. Reference LaRue, Fahey, Alveshere, Atkins, Bhatt, Buma and Chen2023)—change on average with a given increase in temperature? A more straightforward assessment of shifts in spatial distribution is also possible, as there is modern (Lenoir et al. Reference Lenoir, Bertrand, Comte, Bourgeaud, Hattab, Murienne and Grenouillet2020) and past (Wing et al. Reference Wing, Harrington, Smith, Bloch, Boyer and Freeman2005; McElwain Reference McElwain2018) evidence of species ranges tracking climate. Still, the signal is complex (Reddin et al. Reference Reddin, Kocsis and Kiessling2018, Reference Reddin, Nätscher, Kocsis, Pörtner and Kiessling2020), primarily due to sampling constraints and limited temporal resolution, and merits further examination (CPP5). In isolation from or in combination with range shifts, the degree to which species can adapt their niches over time is crucial to predicting how they will respond to ongoing climate change (CPP6). Fossil data support niche stability at low taxonomic levels (Hopkins et al. Reference Hopkins, Simpson and Kiessling2014; Saupe et al. Reference Saupe, Hendricks, Peterson and Lieberman2014; Stigall Reference Stigall2014; Antell et al. Reference Antell, Kiessling, Aberhan and Saupe2020); however, thermal tolerances have evolved across the domains of life (Storch et al. Reference Storch, Menzel, Frickenhaus and Pörtner2014), suggesting that the rate and relative frequency at which tolerances evolve are key features in niche evolution.

The impacts of climate change on biotic systems are numerous (Pörtner Reference Pörtner2021), but cascading effects are less well known (CPP7; e.g., Pecl et al. Reference Pecl, Araújo, Bell, Blanchard, Bonebrake, Chen and Clark2017; Słowiński et al. Reference Słowiński, Skubała, Zawiska, Kruk, Obremska, Milecka and Ott2018). For example, differential range shifts of species in response to climate may lead to novel communities, with new biotic interactions and elevated potential for secondary extinctions (ED9; Pecl et al. Reference Pecl, Araújo, Bell, Blanchard, Bonebrake, Chen and Clark2017; Chiarenza et al. Reference Chiarenza, Waterson, Schmidt, Valdes, Yesson, Holroyd and Collinson2023). Identifying cascading effects in the fossil record is likely difficult but important to reveal the interplay of abiotic and biotic drivers under climate change (O’Keefe et al. Reference O’Keefe, Dunn, Weitzel, Waters, Martinez, Binder and Southon2023).

Conservation Paleobiology (CPB; Table 11)

Conservation paleobiology, which seeks to apply the methods and theories of paleontology to the conservation and restoration of biodiversity and ecosystem services (Dietl et al. Reference Dietl, Kidwell, Brenner, Burney, Flessa, Jackson and Koch2015), has emerged as a pathway for paleontologists to engage with conservation issues. A key theme in these questions is the integration of multiple types of data and methods across scales (CPB2, CPB4, CPB6, Table 11) to provide insights about biodiversity change (CPB3–CPB5, CPB8). Questions in this section crosscut many of the other sections—especially “Climate Change Past and Present”—as conservation paleobiology is an emergent area of research in paleontology that is informed by the entire discipline.

Many paleontologists are seeking ways to more directly connect their science to practice (CPB1, CPB2, CPB8; Dillon et al. Reference Dillon, Pier, Smith, Raja, Dimitrijević, Austin and Cybulski2022). Although there are several success stories of paleontological data application (e.g., Everglades restoration; Marshall et al. Reference Marshall, Wingard and Pitts2014), only 10.8% of published conservation paleobiology studies have had a demonstrable effect on conservation practice (comparable to other areas of conservation science; see Groff et al. Reference Groff, MacKenzie, Pier, Shaffer and Dietl2023). A cultural shift in the norms and practices of the paleontological community is required to produce research results that more closely align with the needs and concerns of practitioners (Dietl et al. Reference Dietl, Durham, Clark and Prado2023). How to get there is a big question (CPB1). At the same time, questions that form the theoretical basis for conservation paleobiology (CPB3–CPB7) remain research priorities, offering opportunities for scientific progress while highlighting gaps in our understanding of biodiversity and ecosystem function and, by extension, ecosystem services (Dillon et al. Reference Dillon, Pier, Smith, Raja, Dimitrijević, Austin and Cybulski2022). For example, it remains a significant challenge to untangle the different drivers that push ecosystems beyond their natural limits and to understand the resulting responses over time (CPB5). The extent to which paleoecological records can be utilized to broaden the temporal perspective for detecting critical transitions in ecosystems and signals of changing resilience (CPB7) is also not fully understood. Nor is it known how, and under which circumstances, looking to the past can contribute productively to setting baselines for ecosystem recovery (CPB4) or anticipating a climate-changed future (CPB3). Such knowledge could support conservation management and planning efforts designed to help reduce the loss of biodiversity and ecosystem services (CPB8) in the face of environmental change. Theoretical development in these areas is foundational for paleontology and is essential for the discipline to grow as an applied area of research to provide insights about future changes in the human-dominated world (Dietl and Flessa Reference Dietl and Flessa2011; Dietl et al. Reference Dietl, Kidwell, Brenner, Burney, Flessa, Jackson and Koch2015, Reference Dietl, Smith and Durham2019; Barnosky et al. Reference Barnosky, Hadly, Gonzalez, Head, Polly, Lawing and Eronen2017; Dillon et al. Reference Dillon, Pier, Smith, Raja, Dimitrijević, Austin and Cybulski2022; Pimiento and Antonelli Reference Pimiento and Antonelli2022; Groff et al. Reference Groff, MacKenzie, Pier, Shaffer and Dietl2023; Kiessling et al. Reference Kiessling, Smith and Raja2023; Kowalewski et al. Reference Kowalewski, Nawrot, Scarponi, Tomašových and Zuschin2023; Zuschin Reference Zuschin2023).

Table 11.

Big Questions for the working group on “Conservation Paleobiology”

Fundamental Issues (FI; Table 12)

Every scientific discipline relies on a dedicated community and supportive infrastructure. To protect paleontology’s foundational resources, infrastructure updates are needed (FI1, FI3, FI5, Table 12). Best practices for collecting, curating, and archiving paleontological data and heritage are developing, but a consensus remains a work in progress (FI1). Assigning specimens an accurate taxonomy in a sound systematic framework is critical for their utility and inclusion in a shareable resource (e.g., GBIF, iDigBio, the Paleobiology Database, FI3; Marshall et al. Reference Marshall, Finnegan, Clites, Holroyd, Bonuso, Cortez and Davis2018). The accuracy and resolution of taxonomic identifications strongly affect biodiversity measurements and interpretation, but this fundamental work is consistently undervalued in the current system for rewarding academics (FI3; Agnarsson and Kuntner Reference Agnarsson and Kuntner2007; Mabry et al. Reference Mabry, Zapata, Paul, O’Connor, Soltis, Blackburn and Simmons2022; Salvador et al. Reference Salvador, Cavallari, Rands and Tomotani2022; Smith et al. Reference Smith, Raja, Clements, Dimitrijević, Dowding, Dunne and Gee2023b). As a result, taxonomic expertise is under threat (e.g., Agnarsson and Kuntner Reference Agnarsson and Kuntner2007; Salvador et al. Reference Salvador, Cavallari, Rands and Tomotani2022). Even so, novel methods for taxonomic analysis (e.g., machine learning; Romero et al. Reference Romero, Kong, Fowlkes, Jaramillo, Urban, Oboh-Ikuenobe, D’Apolito and Punyasena2020; De Baets Reference De Baets2021; Punyasena et al. Reference Punyasena, Haselhorst, Kong, Fowlkes and Moreno2022; Abdelhady et al. Reference Abdelhady, Seuss, Jain, Abdel-Raheem, Elsheikh, Ahmed, Elewa and Hussain2024; Adaïmé et al. Reference Adaïmé, Kong and Punyasena2024) hold the potential to make taxonomic work more efficient, reproducible, and sustainable. Reliable taxonomic, locality, and stratigraphic information are essential for building physical (e.g., samples) and digital (e.g., metadata, imagery) storage infrastructure that allows comparison and integration among researchers and scientific disciplines (Löbl et al. Reference Löbl, Klausnitzer, Hartmann and Krell2023). These improvements require a community effort that is supported by sustainable long-term funding—particularly in the Global South (e.g., Valenzuela-Toro and Viglino Reference Valenzuela-Toro and Viglino2021; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022). This funding can enable expanded accessibility, use, and combination of data, all of which are critical for facilitating interdisciplinary research (Allmon et al. Reference Allmon, Dietl, Hendricks, Ross, Rosenberg and Clary2018; Kaufman et al. Reference Kaufman2018; Smith et al. Reference Smith, Raja, Clements, Dimitrijević, Dowding, Dunne and Gee2023b). Through interdisciplinary research and study programs, the field can continue to expand (FI3). For example, studies of prehistory demonstrate long-standing human collection and use of fossils from the middle Pleistocene onward, creating new opportunities to understand human behavior through interactions with fossils (Cortés-Sánchez et al. Reference Cortés-Sánchez, Simón-Vallejo, Corral, Lozano-Francisco, Vera-Peláez, Jiménez-Espejo and García-Alix2020). Interdisciplinarity will continue to generate new creative approaches with valuable perspectives from other disciplines (e.g., archaeology, biology) while providing new insights on long-pursued questions in paleontology (FI2–FI4).

Table 12.

Big Questions for the working group on “Fundamental Issues”

Paleontology is also economically and societally important (FI4, FI5). Economic contributions include resource exploration, regional tourism (Perini and Calvo Reference Perini and Calvo2008; Kibria et al. Reference Kibria, Akhundjanov and Oladi2019), and diverse products based on paleontological research (e.g., books, clothing, film and television works, theme parks, toys, video games). Aside from these outputs, paleontology requires greater valorization within the scientific community and broader public (FI4, FI5; Plotnick et al. Reference Plotnick, Anderson, Carlson, Jukar, Kimmig and Petsios2023). Geosites are non-renewable areas important for understanding Earth’s history through the observation of biological and geological phenomena. Protecting and conserving important outcrops (e.g., Atkinson et al. Reference Atkinson, Buta, Kopaska-Merkel, Buta, Rindsberg and Kopaska-Merkel2005; Maran Reference Maran2014; Mexicana Reference Mexicana2020; Neto De Carvalho et al. Reference Neto De Carvalho, Baucon, Bayet-Goll and Belo2021; Carvalho and Leonardi Reference Carvalho and Leonardi2022) and access to them necessitate transparent discussion among all who interact with and care about the sites (e.g., paleontologists, landowners, traditional custodians of the land, universities, industrial companies, museums, government). Additionally, collection spaces are the physical repositories of our geoheritage (e.g., museums, geological surveys) and require sustained support from governments, academics, and the public. The primary evidence that paleontologists rely on (physical specimens) is under threat due to restructuring in funding models and museum closures, which removes from the public a pathway for engagement with geoheritage. Public engagement provides a valuable means to increase the profile of paleontology. This work and the people involved in it require significant investment to draw together science, economy, and culture to care for Earth and life’s heritage (FI1, FI4, FI5).

As scientists, we have a responsibility to communicate with the public about our work, yet many researchers receive no formal training on how to perform this duty (e.g., Salvador et al. Reference Salvador, Tomotani, O’Donnell, Cavallari, Tomotani, Salmon and Kasper2021), and these activities are secondary in hiring and promotion decisions (FI2, FI4; e.g., Davies et al. Reference Davies, Putnam, Ainsworth, Baum, Bove, Crosby and Côté2021; Raja and Dunne Reference Raja and Dunne2022). Without an informed public, policymakers cannot craft legislation that benefits the greatest number of people, and individuals cannot make accurate data-driven decisions. The roles of paleontologists continue to diversify, with a large proportion of graduates working outside academia in settings with variable skill requirements (FI2; e.g., industry, conservation, education, government; Keane et al. Reference Keane, Gonzales and Robinson2021). Paleontologists need skills to make them academically, economically, and socially valuable so they can share information about the long-term changes and variability that life on Earth has experienced with increased proficiency.

Looking Inward and Outward (LIO; Table 13)

Whereas paleontologists are keenly aware of the taphonomic biases constraining our view of past biodiversity, we have not systematically studied the biases linked to the identities and practices shaping how we collect, analyze, and interpret the fossil record. Presently, socioeconomic factors disproportionately influence the sampling coverage of both modern ecosystems and past biodiversity (Cisneros et al. Reference Cisneros, Raja, Ghilardi, Dunne, Pinheiro, Fernández and Sales2022; Monarrez et al. Reference Monarrez, Zimmt, Clement, Gearty, Jacisin, Jenkins and Kusnerik2022; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022). Many perspectives and data are missing, which contributes to an incomplete understanding of past and present global biodiversity and restricts the development of ecological and evolutionary theory (LIO1, Table 13; Mohammed et al. Reference Mohammed, Turner, Fowler, Pateman, Nieves-Colón, Fanovich and Cooke2022; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022). Identifying and addressing these biases and challenges in paleontology (e.g., dominance of the English language; Cisneros et al. Reference Cisneros, Raja, Ghilardi, Dunne, Pinheiro, Fernández and Sales2022; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022) and incorporating as many diverse perspectives as possible will lead to a better understanding of all aspects of life on Earth (LIO2, LIO3).

Table 13.

Big Questions for the working group on “Looking Inward and Outward”

Though many people globally have undertaken the study of past life, including within Indigenous traditions and local communities (Mayor Reference Mayor2007; Benoit et al. Reference Benoit, Penn-Clarke, Rust, Groenewald, Vickers-Rich and Helm2024), the earliest data points of Western academic paleontology are tied to the expansion of colonial empires (Monarrez et al. Reference Monarrez, Zimmt, Clement, Gearty, Jacisin, Jenkins and Kusnerik2022; Scarlett Reference Scarlett2022). Current research infrastructure is often built on these colonial legacies, including specimens held in museum collections (LIO4; Bradley et al. Reference Bradley, Adgemis and Haralampou2014; Cisneros et al. Reference Cisneros, Raja, Ghilardi, Dunne, Pinheiro, Fernández and Sales2022; Mohammed et al. Reference Mohammed, Turner, Fowler, Pateman, Nieves-Colón, Fanovich and Cooke2022; Monarrez et al. Reference Monarrez, Zimmt, Clement, Gearty, Jacisin, Jenkins and Kusnerik2022; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022). Digitization efforts are making museum collections and exhibits more accessible internationally to those with internet access, but digital representations do not necessarily provide the same research and engagement opportunities as physical specimens and have their own complications (e.g., compliance with sharing policies, digital quality and resolution, large file sizes, internet access and bandwidth; Falkingham Reference Falkingham2012; Lewis Reference Lewis2019). Natural history specimens and geosites are often considered to be natural heritage items (including status as UNESCO sites, https://whc.unesco.org/en/list), and calls for repatriation are growing in number (Bradley et al. Reference Bradley, Adgemis and Haralampou2014; Vogel Reference Vogel2019), making evaluating this issue in paleontology a priority (LIO4; see “Fundamental Issues”).

Researchers, institutions, and funding bodies must make proactive decisions to avoid contributing further to colonial legacies by evaluating the power dynamics of international collaborations while contending with the curation of specimens collected in the past (LIO5; e.g., Dunne et al. Reference Dunne, Raja, Stewens, Zin-Maung-Maung-Thein and Zaw2022). These decisions can run counter to incentives for publication on “novelty” and unique specimens, which are often gleaned from fieldwork in key geographic regions (e.g., Myanmar; LIO6; Dunne et al. Reference Dunne, Raja, Stewens, Zin-Maung-Maung-Thein and Zaw2022; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022).

More broadly, fieldwork is not equally accessible to everyone despite its high value as a component of science education (e.g., Shinbrot et al. Reference Shinbrot, Treibergs, Hernández, Esparza, Ghezzi-Kopel, Goebel and Graham2022). As in all the sciences with fieldwork components, paleontologists must grapple with safety and equity considerations, including mechanisms for reporting sexual harassment and assault (Clancy et al. Reference Clancy, Nelson, Rutherford and Hinde2014), explicit discussions about the safety of people of marginalized identities in field conditions (Demery and Pipkin Reference Demery and Pipkin2021; Rudzki et al. Reference Rudzki, Kuebbing, Clark, Gharaibeh, Janecka, Kramp and Kohl2022), and accessibility and inclusive design of field experiences for people with disabilities (LIO6; Stokes et al. Reference Stokes, Feig, Atchison and Gilley2019).

The exclusion and attrition of groups of people with particular identities and affinities (i.e., minoritized or marginalized groups) from academia have previously been described as a passive, leaky pipeline; however, this metaphor downplays the challenges posed by racism, colonial legacies, and systemic bias at institutional levels, which are now more accurately described as a “hostile obstacle course” (e.g., Bernard and Cooperdock Reference Bernard and Cooperdock2018; Valenzuela-Toro and Viglino Reference Valenzuela-Toro and Viglino2021; Berhe et al. Reference Berhe, Barnes, Hastings, Mattheis, Schneider, Williams and Marín-Spiotta2022; Carter et al. Reference Carter, Johnson and Schroeter2022). Recognizing that these challenges exist, paleontologists must identify and embrace practices that create a more inclusive and equitable culture (LIO7; Valenzuela-Toro and Viglino Reference Valenzuela-Toro and Viglino2021; Carter et al. Reference Carter, Johnson and Schroeter2022; Cisneros et al. Reference Cisneros, Raja, Ghilardi, Dunne, Pinheiro, Fernández and Sales2022; Raja et al. Reference Raja, Dunne, Matiwane, Khan, Nätscher, Ghilardi and Chattopadhyay2022). Current diversity, equity, and inclusion tasks fall disproportionately on minoritized individuals, yet often are not considered in tenure and promotion assessments (LIO8; Jimenez et al. Reference Jimenez, Laverty, Bombaci, Wilkins, Bennett and Pejchar2019). Although individual actions are important, support for diversity, equity, and inclusion must come from the highest levels of leadership (e.g., those making funding decisions) to signal their value (Dutt Reference Dutt2021; Chen et al. Reference Chen, Kahanamoku, Tripati, Alegado, Morris, Andrade and Hosbey2022). In implementing these changes, we can iteratively add to our dataset of changing outcomes in paleontology to evaluate whether such actions are effective (LIO2) and how this affects our understanding of both past and future worlds (LIO1).

Concluding Remarks

The present state of paleontological research is complex and constantly changing. Considering the limited number of paleontologists employed professionally in comparison to other scientific fields (e.g., Keane et al. Reference Keane, Gonzales and Robinson2021; Plotnick et al. Reference Plotnick, Anderson, Carlson, Jukar, Kimmig and Petsios2025), it is prudent to develop a shared research agenda that the paleontological community can jointly address (Fig. 3). The questions presented here are unavoidably influenced by the perspectives of those participating and by the initial set of questions submitted. However, we have attempted to minimize this influence through our strategy for an inclusive approach to question submission, project participation, and authorship. Doing so gives us confidence that these BQs faithfully represent a forward-looking agenda for the discipline of paleontology.

Figure 3.

The Big Questions project can be used as a tool to guide research in paleontology and to advocate for the importance of funding paleontological research.

Whether this list of questions is taken as a whole, separated by theme, or examined piecemeal as individual questions, we encourage all in the paleontological community to use these BQs as a tool for communicating the importance of paleontology and securing research funding. Indeed, as the questions presented here have emerged from a community-wide effort, they likely are more representative of the state of the field than if the exercise was conducted with a top-down approach by a select few individuals, and this element may add credibility and power to arguments for funding in paleontology, broadly. As in other endeavors to define priority questions (e.g., Sutherland et al. Reference Sutherland, Adams, Aronson, Aveling, Blackburn, Broad and Ceballos2009; Seddon et al. Reference Seddon, Mackay, Baker, Birks, Breman, Buck and Ellis2014), we expect a variety of uses (e.g., development of research projects, spurring discussion on the importance of different BQs) and audiences (e.g., other scientists, funding bodies, students, the general public). We anticipate these BQs will be used by researchers as framing and inspiration for new research directions and as a tool they can use to justify paleontological research to funding organizations (Fig. 3). The BQs reiterate the substantive contributions of museums and physical collection spaces, making clear a need for sustained funding of the repositories of our geoheritage. The BQs highlight the breadth and vitality of paleontology and the important and substantive role the discipline will continue to play in pushing the frontiers of understanding throughout the life sciences.

Many of the questions included here are directed at pursuing long-standing hypotheses on how life has evolved and responded to environmental change. A large portion also pertains to the application of paleontological data to the biodiversity and environmental crises that permeate the modern world. Questions in each of these areas share common considerations, including the effects of scale on observations and the ever-present challenge of assessing the adequacy of the fossil record to address these questions. Reflecting larger ongoing discussions in science and society, there is also an emphasis on conducting paleontological research more inclusively and equitably as a community. Through efforts like this Big Questions project that bring together groups of people with many backgrounds, expertises, and motivations, we aspire to grow and strengthen the global paleontological community. Our collective understanding of the history and future of life on Earth will only be improved by creating a cohesive discipline where all interested individuals can contribute.