Evidence for clinging arboreality in a Middle Jurassic stem lepidosaur

Lepidosaurs are an ecologically diverse and speciose group with more that 11,000 living species (squamates and the tuatara). Stem lepidosaurs are known from the Early Triassic onwards, but primarily from very incomplete specimens. Therefore, we have little information on their ecological diversity or the ecological context of deep evolutionary divergences of Lepidosauria. Marmoretta oxoniensis, from the Middle Jurassic of the UK, is one of the most completely known candidate stem lepidosaurs. Previous studies proposed that it may have been semiaquatic, based primarily on its abundance in marginal marine rocks. We show here that Marmoretta was adapted for climbing, based on the postcranial anatomy of a partial skeleton, visualised using micro-computed tomography (µCT), in particular, the steep angles of thoracic zygapophyses, ungual phalanx morphology, and elongate penultimate manual phalanges that curve distoventrally along their lengths. Linear discriminant analysis of the partial hand..., , , # Data from: Evidence for clinging arboreality in a Middle Jurassic stem lepidosaur

[https://doi.org/10.5061/dryad.t4b8gtjc8](https://doi.org/10.5061/dryad.t4b8gtjc8)

## Description of the data and file structure

**Description of the data and file structure**

1. Fontanarrosa et al. 2018 subset.csv - squamate forelimb bone measurements with subset of manus only measurements. for use as a training set to evaluate habitat use in *Marmoretta*.
2. Fossil measurements for Marmoretta.csv - measurements of the manus obtained from 3D models of *Marmoretta*.
3. Marmoretta postcranial skeleton script 07Jan2025.R - R script used for phylogenetic regression, PCA, and LDA.
4. Tonini_et_al_trees for Marmoretta post crania.tre - 50 trees randomly taken from the tree distribution of Tonini et al. 2016 to provide a phylogenetic framework for phylogenetic regression.
5. MrBayes_script_for_Mkv_run_new_Marmoretta - text file with script for MrBayes run, based on the phylogenetic analysis in Ford et al. ...,

鳞龙类（Lepidosaurs）是一类生态多样且物种丰富的类群，现存物种超过11000种，涵盖有鳞类（squamates）与喙头蜥（tuatara）。干群鳞龙类的化石记录可追溯至早三叠世，但相关标本大多保存极不完整，因此我们对鳞龙超目的生态多样性以及其深层演化分歧的生态背景知之甚少。

产自英国中侏罗世的牛津马尔莫雷蜥（Marmoretta oxoniensis）是目前已知保存最为完整的候选干群鳞龙类之一。此前的研究主要基于其在近岸海相岩石中的高丰度，推测该物种可能为半水生。本次研究通过对一件部分保存的颅后骨骼（经显微计算机断层扫描（µCT）可视化）的解剖结构分析，证明马尔莫雷蜥实际适应攀爬行为：其胸椎关节突夹角陡峭、爪骨形态特殊，且手部倒数第二指节修长并沿长轴向腹远端弯曲。对其部分手部骨骼的线性判别分析……
# 数据来源：中侏罗世干群鳞龙类具备攀附树栖能力的证据
[https://doi.org/10.5061/dryad.t4b8gtjc8](https://doi.org/10.5061/dryad.t4b8gtjc8)

## 数据与文件结构说明
1. Fontanarrosa et al. 2018 subset.csv：仅包含手部骨骼测量数据的有鳞类前肢骨骼测量子集，用于作为训练集以评估马尔莫雷蜥的生境偏好。
2. Fossil measurements for Marmoretta.csv：从马尔莫雷蜥的三维模型中获取的手部骨骼测量数据。
3. Marmoretta postcranial skeleton script 07Jan2025.R：用于系统发育回归、主成分分析（PCA）以及线性判别分析（LDA）的R脚本。
4. Tonini_et_al_trees for Marmoretta post crania.tre：从Tonini等人2016年的树分布中随机抽取的50棵系统发育树，用于为系统发育回归提供系统发育框架。
5. MrBayes_script_for_Mkv_run_new_Marmoretta：基于Ford等人的系统发育分析编写的MrBayes运行脚本文本文件。