Global and local effects of long-term environmental change: a turtle's eye view

Lead Research Organisation: The Natural History Museum
Department Name: Earth Sciences

Abstract

Turtles, tortoises, and terrapins (collectively termed chelonians) are an immensely successful group of vertebrates that have endured for over 220 million years. They have persisted through numerous major environmental perturbations, including the formation of global hothouse conditions in the Late Cretaceous and Eocene (and associated cooling events), the end-Cretaceous mass extinction, and post-Eocene global cooling trends. How have they responded to these past environmental changes? What can we learn from their history that can be applied to understand past and future responses of biota to long-term environmental change? Chelonians inhabit all three major global realms (marine, freshwater, terrestrial) and chelonian fossils are exceptionally common, have a well-established taxonomy, and their habitat preferences are well-understood. For all of these reasons, chelonians are a near-ideal model system for studying the biotic response of cold-blooded vertebrates to long-term environmental change. This is because we can compare groups characteristic of different habitats and regions as a replicated natural experiment to understand the differential effects of long-term change on ecological subsets of global diversity. Moreover, chelonians are globally threatened, and study of their past reactions to major environmental events will provide the baseline information needed to help predict their possible responses to projected future climate change.

The proposed project is completely novel. We will build a comprehensive database of all chelonian occurrences in the Mesozoic and Paleogene (220-23 million years ago). We will use these data to construct the first-ever rigorous estimate of global chelonian diversity during this interval. We will apply standard and newly developed statistical methods to extract the signal of diversity change from noise resulting from uneven sampling or other biases in the fossil record. We will then use these data to understand how chelonian diversity patterns differ among habitats and regions. Do changes in different regions and habitats occur out of phase or do they act together to create the global pattern?

Most importantly, we will compare the observed diversity patterns with palaeoclimatic data, such as mean annual temperature and precipitation rates, in order to determine if any significant positive (evolutionary radiation or decreased extinction) or negative (decreased origination or increased extinction) changes in chelonian diversity correlate with global or regional environmental perturbations. All of this work will lead to the most detailed understanding of the relationship between chelonian diversity, distribution and climate ever attempted. This will greatly advance our understanding of long-term biotic responses to global change, will be timely in complementing existing work on other groups (primarily mammals), and will provide a deep-time perspective on current biodiversity trends in chelonians and other reptiles. These insights from the fossil record, the only dataset capable of documenting the long-term impacts of climate change, will be of direct relevance to those working on living species. We think that our results will be of major importance to zoologists, conservation biologists, palaeontologists, palaeoclimatologists and macroecologists.

Planned Impact

The impact of this research will benefit four major groups of stakeholders in the UK and internationally:

1. The international scientific community, primarily those working on long-term responses of organisms to global climate change, specifically vertebrate palaeontologists, zoologists, climate scientists and macroecologists.
2. Non-governmental organisations (NGOs), including UK and internationally-based conservation charities, and UK government agencies charged with assessing the impact of predicted long-term climate change on biodiversity conservation strategies.
3. The UK public, which has high levels of societal interest in scientific issues relating to both long-term climate change and palaeontology/evolution.
4. UK-based science educators in schools and colleges, as the proposed project is of direct relevance to topics covered by the National Curriculum, namely biodiversity and the impact of environmental change.

Impact will be achieved in the following ways:

1. Scientific publication in high-profile international journals and presentations at professional meetings (communication with the academic community, NGOs, government agencies).
2. Popular scientific articles in the membership magazines of NGOs, such as those of the World-Wide Fund for Nature (WWF-UK), in Natural History Museum publications, and elsewhere as invited.
3. A range of public outreach activities aimed a both school groups and the general public to be held in the NHM, in conjunction with the museum's educational specialists. These activities will include: 'Nature Live' events (aimed at the public, school groups), which involve 30 minute presentations with the museum and that allow direct communication between the scientists and audience; formal activity-based education events (for both primary and secondary pupils); and provision of a mobile exhibition ('Hands-on Nature') for use with the NHM public galleries (aimed at the public and primary school groups).
4. Public outreach beyond the NHM will include video-conferencing sessions with school groups around the UK. In addition, the 'Hands-on Nature' exhibit will be suitable for touring at other venues, including public science festivals.
5. NGOs (e.g. WWF-UK, Durrell Foundation, Institute of Zoology [IoZ]) and governmental agency representatives (e.g. DEFRA, Natural England) will be invited to attend a half-day workshop on the results of the project, accompanied by a briefing document on how this research might impact future biodiversity and conservation priorities and policy. WWF-UK and the IoZ have already expressed strong interest in the possible benefits of the proposed research (see Letters of Support).

The NHM is ideally placed to promote the results of the research to an exceptionally wide audience. The museum already has excellent, purpose-built facilities in place to deliver many of these activities and an unmatched track record in communicating science to a diverse set of stakeholders.

Publications

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Nicholson DB (2015) Climate-mediated diversification of turtles in the Cretaceous. in Nature communications

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Nicholson DB (2016) Latitudinal diversity gradients in Mesozoic non-marine turtles. in Royal Society open science

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Waterson AM (2016) Modelling the climatic niche of turtles: a deep-time perspective. in Proceedings. Biological sciences

 
Description Work still continues using the data provided, and several planned publications have been held up in review, so results are currently incomplete. However, we have compiled a large amount of new data on the distribution of fossil turtles in time and space and used this information to compile the first estimates of their diversity through the Mesozoic Era (250-66 million years ago). The overall diversity pattern is strongly affected by various geological and sampling biases, but once these were corrected we find evidence for high points and declines that coincide with major global climatic events. Moreover, we have found strong links between turtle latitudinal ranges and past climates, which has implications for modern conservation work. The tied PhD studentship has generated new approaches to modelling ecological distributions in deep time and the first results of this work are now published and consist of a niche model for predicting turtle distributions in time and space. This work has been validated with modern taxa and has been shown to have strong predictive power with respect to the distributions of extinct turtles. Work is continuing to analyse the diversity and distribuitions of Paleogene turtles. Two additional papers arising from this one, one on turtle diversity through the Mesozoic/Paleogene and one on predictive modelling of turtle distribution in relation to climate, are currently in preparation. 1000+ new entries for fossil turtle data have thus far been added to an open access online database for fossil occurrences.
Exploitation Route This work has strong potential to be used as baseline data by conservation agencies interested in mitigating biodiversity changes to turtle species and populations in the face of global change, as well as numerous educational outlets on global change biology and evolution in deep time.
Sectors Education,Environment,Culture, Heritage, Museums and Collections

 
Description Three public lectures have been given on the results of our work at the Natural History Museum (Nature Live talk series, two in 2015 and one in 2016) and we also contributed to the EU Researcher Night events via participation in the Science Uncovered night at the NHM in September 2015, with a stall explaining our work to the general public - this resulted in numerous engagements at an event attended by over 10,000 members of the public. A second public event at the NHM (NHM Lates) allowed us another opportunity to engage with the public (with several thousand visitors), as did a one-day open meeting where a series of talks was presented to a general auduence at the NHM (around 120 participants). Our work has also been covered by the media following a press release on one our high-impact papers. An in-gallery activity was also developed as part of the impact plan, showing how turtle diversity, tree ring formation and ice core data could all be related to climate. This activity has engaged 2378 children (both in school groups and in family visits) and 2366 adults within the NHM between May 2017-January 2018.
First Year Of Impact 2015
Sector Education,Environment,Culture, Heritage, Museums and Collections
Impact Types Cultural,Societal

 
Title Additional of new data to PBDB 
Description We added numerous new entries and modifications to the Paleobiology Database (>1,000) dealing with turtle distribution in the Mesozoic and Paleogene and cleaning taxonomic records and opinions within the data. 
Type Of Material Database/Collection of data 
Year Produced 2016 
Provided To Others? Yes  
Impact These data are essential to our own analyses and are now available for others wanting to examine fossil turtle distributions: we know of at least three other research groups (one in Germany, one in Argentina and one in the UK) that are now using this information. 
URL https://paleobiodb.org/
 
Description In-gallery activity 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact An in-gallery activity was designed in collaboration with the NHM Education Team to showcase the links between biodiversity and climate through time. A series of interlinked themes were developed, where the public were asked to reconstruct biodiversity using fragments of fossil turtle shell (which is taxonomically informative) and then to compare the diversity of different fossil faunas with a palaeotemperature curve. Parallel examples using tree ring data and ice core data were also added to szhow how palaeoclimatologists reconstruct past climate and to demonstrate how these past changes might have affected biodiversity. The activity kit included fossil turtles, replicas of extant turtles, worksheets with palaeoclimate information, sections of tree rings with interpretative diagrams, and a model ice core. The activity was manned by specialist science educators in the public galleries of the natural history museum and has engaged 4,700 visitors so far (figures May 2017-January 2018).
Year(s) Of Engagement Activity 2017,2018
 
Description Media attention for Proceedings B paper 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact A press release was issued to highlight the publication of a paper dealing with niche modelling in extinct turtles and how the responses of these turtles to past environmental change could inform our conservation strategies under scenarios of current climate change (published in Proceedings B). The press release was picked up by various outlets and reported in the popular media. Further requests for information about our work followed as a result, both from the media and from colleagues. This release also resulted in three independent blog pieces dealing with a discussion of this paper.
Year(s) Of Engagement Activity 2016
URL http://www.express.co.uk/news/nature/712636/global-warming-no-problem-endangered-turtles-tortoises
 
Description NHM Lates Event 2016 (NHM) 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact We provided a display at an evening event hosted by the Natural History Museum, London entitled 'NHM Lates'. This involved bringing relevant museum collections out into the public realm to illustrate turtle evolution and diversity (including material of both living and extinct turtles) and preparing a number of handouts and graphics to explain the effects of climate change on turtle distribution under current scenarios of climate change and through deep time. The evening involved numerous direct interactions with >100 members of the public, many of whom were previously unaware of the threats that turtles are facing in a warming world and that were also unaware of the long evolutionary history of the group.
Year(s) Of Engagement Activity 2016
 
Description Nature Live Talk at the NHM London 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact Nature Live Talk at the NHM London ("Turtley not cool") (November 2016) - question and answer session with a general public audience on the findings of the Proc B paper.
Year(s) Of Engagement Activity 2016
 
Description Nature Live presentation (NHM) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact The PhD student associated with the project gave a public talk on the results of her work as part of the Natural History Museum's Nature Live series of talks, to an audience of around 50-60 members of the general public. This talk outlined work on changes in turtle habitat and ecology through time and showed how work on the past can illuminate work on the responses of turtles to current climate change. Many of the audience members asked questions and expressed surprise and interest in the work and how they were previously unaware of the threats faced by turtles today.
Year(s) Of Engagement Activity 2016
 
Description Nature Live, Natural History Museum, July 2015 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Hosted presentation given to a mixed audience of approximately 60-70 attendees. Let to numerous audience interactions and questions with the audience reporting positively on the information presented in the event.
Year(s) Of Engagement Activity 2015
 
Description One day public meeting (NHM) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Public/other audiences
Results and Impact A one day conference, open to all and free to attend, that brought together experts on both living and extinct reptiles and reviewed the impact of current and future climate change on reptile diversity and distriubution. The meeting brought together two different parts of the academic community and attracted a large audience from the public, students and fellow academics. The intended purpose of the activity was to raise awareness of the impacts of current climate change on reptiles and also to show that using data from the fossil record could provide useful baseline data to assess current trends. There was extensive discussion at the meeting during break-out sessions and discussions on collaborations between those dealing with current issues and palaeontological data. The meeting attracted social media attention and led to a number of follow-up questions from many attendees. Over 120 people registered to attend the meeting.
Year(s) Of Engagement Activity 2016
URL https://www.eventbrite.co.uk/e/climate-cold-blood-reptile-responses-to-past-and-present-climate-chan...
 
Description Science Uncovered Event, Natural History Museum, Sep 2014 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Two hours (in two separate sessions) talking about the outcomes of the project with a general audience in the 'Science Bar' at the EU-sponsored Science Uncovered Event. This led to numerous questions and discussion with many members of the general public attending the event.
Year(s) Of Engagement Activity 2014
 
Description Science Uncovered Event, Natural History Museum, Sep 2015 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Stand at major public outreach event attended by thousands of members of the public and school children. Numerous interactions with the public, with many questions and requests for additional information.
Year(s) Of Engagement Activity 2015
 
Description Seminar in IVPP Beijing 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact I gave an invited seminar on this project to an audience of around 35 Chinese colleagues in the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing (April 2016). The audience was unfamiliar with the various analtyical techniques that we had applied to our dataset and so this resulted in extensive discussion and requests for new information, as well as later information exchange.
Year(s) Of Engagement Activity 2016