File name: Nicholson_et_al_Dataset_2_ESM.xlsx Title: Dataset 2Description: Calculations for palaeo-non-marine area at 15 degree palaeolatitudinal bands for Jurassic, Lower Cretaceous and Upper Cretaceous time bins used in GLS analyses from Latitudinal diversity gradients in Mesozoic non-marine turtles

The latitudinal biodiversity gradient (LBG)–the pattern of increasing taxonomic richness with decreasing latitude–is prevalent in the structure of the modern biota. However, some freshwater taxa show peak richness at mid-latitudes; for example, extant Testudines (turtles, terrapins and tortoises) exhibit their greatest diversity at 25° N, a pattern sometimes attributed to recent bursts of climatically mediated species diversification. Here, we test whether this pattern also characterizes the Mesozoic distribution of turtles, to determine whether it was established during either their initial diversification or as a more modern phenomenon. Using global occurrence data for non-marine testudinate genera, we find that subsampled richness peaks at palaeolatitudes of 15 – 30° N in the Jurassic, 30 – 45° N through the Cretaceous to the Campanian, and from 30° to 60° N in the Maastrichtian. The absence of a significant diversity peak in southern latitudes is consistent with results from climatic models and turtle niche modelling that demonstrate a dearth of suitable turtle habitat in Gondwana during the Jurassic and Late Cretaceous. Our analyses confirm that the modern testudinate LBG has a deep-time origin and further demonstrate that LBGs are not always expressed as a smooth, equator-to-pole distribution

A new dermatemydid (Testudines, Kinosternoidea) from the Paleocene-Eocene Thermal Maximum, Willwood Formation, southeastern Bighorn Basin, Wyoming

<div><p>ABSTRACT</p><p><i>Gomphochelys nanus</i>, new genus and species, is described from the earliest Wasatchian (biohorizon Wa 0; ∼55.8 Ma) of the southeastern Bighorn Basin, Washakie County, Wyoming. The new taxon represents the only known dermatemydid from the Paleocene–Eocene Thermal Maximum (PETM) interval and extends the lineage back from previous records by approximately 2 million years. <i>Gomphochelys nanus</i> has a thick tricarinate carapace and differs from other dermatemydids in attaining a smaller adult body size, having reduced plastral features, a posteriorly situated gular–humeral sulcus, an acarinate pygal, and thick shortened peripherals. Reexamination of previously described fossil dermatemydids suggests that the taxa <i>Baptemys tricarinata</i> and <i>Kallistira costilata</i> are junior synonyms of the middle–late Wasatchian <i>Notomorpha garmanii</i>, and <i>Baptemys fluviatilis</i> is likely a junior synonym of <i>Baptemys wyomingensis</i>. <i>Gomphochelys nanus</i> is a stem dermatemydid that is similar to <i>N. garmanii</i> but differs in possessing symplesiomorphies with the Late Cretaceous–Paleocene genera <i>Agomphus</i> and <i>Hoplochelys</i>. Aspects of shell morphology suggest that <i>G. nanus</i> was a commensurate swimmer and bottom-walker like extant <i>Dermatemys</i> and <i>Staurotypus</i>. The presence of a dermatemydid (a tropically distributed clade) in the southeastern Bighorn Basin during the PETM (when global temperatures increased by 5°C–10°C over a period of ∼60 ky) further supports the hypothesis that climate was megathermal in the region during this interval and is consistent with previously documented geographic range changes in both plants and animals. Dermatemydids disappear from the fossil record at the end of the PETM and don't reemerge until the next warming event, Eocene Thermal Maximum 2.</p><p>http://zoobank.org/urn:lsid:zoobank.org:pub:19A98079-5CAD-4BC5-8C21-2810AA576D98 </p><p>SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP</p></div

File name: Nicholson_et_al_manual_splits_9Myr_splits_ESM Title: Time binsDescription: File containing temporal bin information for use in Shareholder Quorum Subsampling analyses from Latitudinal diversity gradients in Mesozoic non-marine turtles

The latitudinal biodiversity gradient (LBG)–the pattern of increasing taxonomic richness with decreasing latitude–is prevalent in the structure of the modern biota. However, some freshwater taxa show peak richness at mid-latitudes; for example, extant Testudines (turtles, terrapins and tortoises) exhibit their greatest diversity at 25° N, a pattern sometimes attributed to recent bursts of climatically mediated species diversification. Here, we test whether this pattern also characterizes the Mesozoic distribution of turtles, to determine whether it was established during either their initial diversification or as a more modern phenomenon. Using global occurrence data for non-marine testudinate genera, we find that subsampled richness peaks at palaeolatitudes of 15 – 30° N in the Jurassic, 30 – 45° N through the Cretaceous to the Campanian, and from 30° to 60° N in the Maastrichtian. The absence of a significant diversity peak in southern latitudes is consistent with results from climatic models and turtle niche modelling that demonstrate a dearth of suitable turtle habitat in Gondwana during the Jurassic and Late Cretaceous. Our analyses confirm that the modern testudinate LBG has a deep-time origin and further demonstrate that LBGs are not always expressed as a smooth, equator-to-pole distribution

File name: Nicholson_et_al_Dataset_1_ESM.xlsx Title: Dataset 1Description: Mesozoic turtle occurrence data downloaded from http://fossilworks.org and associated data summaries used in analyses from Latitudinal diversity gradients in Mesozoic non-marine turtles

The latitudinal biodiversity gradient (LBG)–the pattern of increasing taxonomic richness with decreasing latitude–is prevalent in the structure of the modern biota. However, some freshwater taxa show peak richness at mid-latitudes; for example, extant Testudines (turtles, terrapins and tortoises) exhibit their greatest diversity at 25° N, a pattern sometimes attributed to recent bursts of climatically mediated species diversification. Here, we test whether this pattern also characterizes the Mesozoic distribution of turtles, to determine whether it was established during either their initial diversification or as a more modern phenomenon. Using global occurrence data for non-marine testudinate genera, we find that subsampled richness peaks at palaeolatitudes of 15 – 30° N in the Jurassic, 30 – 45° N through the Cretaceous to the Campanian, and from 30° to 60° N in the Maastrichtian. The absence of a significant diversity peak in southern latitudes is consistent with results from climatic models and turtle niche modelling that demonstrate a dearth of suitable turtle habitat in Gondwana during the Jurassic and Late Cretaceous. Our analyses confirm that the modern testudinate LBG has a deep-time origin and further demonstrate that LBGs are not always expressed as a smooth, equator-to-pole distribution

File name: Nicholson_et_al_Mesozoic_latitude_script_ESM.R Title: Mesozoic turtle latitude analyses R scriptDescription: R script for cleaning and partitioning Mesozoic turtle occurrence data into 15 degree palaeolatitudinal bands and various temporal bins, Shareholder Quorum Subsampling and generalised least squares regression analyses. from Latitudinal diversity gradients in Mesozoic non-marine turtles

The latitudinal biodiversity gradient (LBG)–the pattern of increasing taxonomic richness with decreasing latitude–is prevalent in the structure of the modern biota. However, some freshwater taxa show peak richness at mid-latitudes; for example, extant Testudines (turtles, terrapins and tortoises) exhibit their greatest diversity at 25° N, a pattern sometimes attributed to recent bursts of climatically mediated species diversification. Here, we test whether this pattern also characterizes the Mesozoic distribution of turtles, to determine whether it was established during either their initial diversification or as a more modern phenomenon. Using global occurrence data for non-marine testudinate genera, we find that subsampled richness peaks at palaeolatitudes of 15 – 30° N in the Jurassic, 30 – 45° N through the Cretaceous to the Campanian, and from 30° to 60° N in the Maastrichtian. The absence of a significant diversity peak in southern latitudes is consistent with results from climatic models and turtle niche modelling that demonstrate a dearth of suitable turtle habitat in Gondwana during the Jurassic and Late Cretaceous. Our analyses confirm that the modern testudinate LBG has a deep-time origin and further demonstrate that LBGs are not always expressed as a smooth, equator-to-pole distribution

Phylogeny of genera included in the present analysis.

<p>A dendrogram illustrating the phylogenetic relationships among the genera investigated in the present study <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058667#pone.0058667-Asher3" target="_blank">[11]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058667#pone.0058667-Asher4" target="_blank">[13]</a>-<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0058667#pone.0058667-McKenna1" target="_blank">[18]</a>.</p

Summary of results.

<p>Statistical comparisons of brain/body allometry among the insectivores in the present sample. Results indicate that sengis have relatively larger brains for a given body size compared with other insectivore-grade mammals.</p

Maximum intensity projections of the <i>R. udzungwensis</i> MRI.

<p>Two views of the <i>R. udzungwensis</i> MRI visualized as maximum intensity projections with the brain highlighted in white. A) Antero-lateral oblique view. B) Superior view, scale bar = 5 cm.</p

Brain-body allometry in Macroscelididae vs. other insectivores.

<p>A scatterplot of log body mass on log brain mass in which the RMA line (dashed) for Macroscelididae (n = 5) is compared to the RMA line (solid) describing other insectivores (n = 52). The slopes of the two lines are statistically indistinguishable (common slope  = 0.66; 95% CI: 0.63–0.70). Residual axis scores indicate that the best-fit line describing Macroscelididae has a significantly larger y-intercept than the line describing other insectivores (X² = 142.36, <i>p</i><0.001).</p

Maastrichtian_turtle_PBDBdata from Modelling the climatic niche of turtles: a deep-time perspective

Ectotherms have close physiological ties with the thermal environment; consequently, the impact of future climate change on their biogeographic distributions is of major interest. Here, we use the modern and deep-time fossil record of testudines (turtles, tortoises and terrapins) to provide the first test of climate on the niche limits of both extant and extinct (Late Cretaceous, Maastrichtian) taxa. Ecological niche models are used to assess niche overlap in model projections for key testudine ecotypes and families. An ordination framework is applied to quantify metrics of niche change (stability, expansion and unfilling) between the Maastrichtian and present-day. Results indicate that niche stability over evolutionary timescales varies between testudine clades. Groups that originated in the Early Cretaceous show climatic niche stability, whereas those diversifying towards the end of the Cretaceous display larger niche expansion towards the modern. Temperature is the dominant driver of modern and past distributions, whereas precipitation is important for freshwater turtle ranges. Our findings demonstrate that testudines were able to occupy warmer climates than present day in the geological record. However, the projected rate and magnitude of future environmental change, in concert with other conservation threats, presents challenges for acclimation or adaptation