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Ökomorphologische Konvergenz tritt auf, wenn Arten mit demselben Lebensstil unabhängig voneinander ähnliche morphologische Merkmale evolvieren. Neue Fallstudien können dabei helfen, die diesem Prozess zugrunde liegenden Mechanismen aufzuklären. Diese Arbeit befasst sich mit einigen konvergent evolvierten, langsamen, baumbewohnenden Säugetieren, d. h. zwei Linien baumlebender Faultieren, dem Zwergameisenbär, den Lorisiden, zwei Kladen ausgestorbener Lemuren, d. h. Paläopropithekiden und Megaladapis, und dem Koala. Es werden funktionsmorphologische Konvergenzen in diesen Taxa erforscht, indem ihr Humerus und ihr Femur sowie jene ihrer nah verwandten, aber ökologisch unterschiedlichen Taxa untersucht werden. Erstmals werden Knochen mittels phylogenetisch vergleichender Methoden auf vier anatomischen Ebenen, d.h. äußere Form, diaphysäre Mikrostruktur und Anatomie sowie epiphysäre Trabekelarchitektur, analysiert. Viele langsame, baumbewohnende Säugetiere teilen eine geringe kortikale Kompaktheit, was wahrscheinlich mit ihrer extrem niedrigen Stoffwechselrate und ihren biomechanischen Anforderungen zusammenhängt. Langsame, arboreale Xenarthra, d. h. baumbewohnende Faultiere und der Zwergameisenbär, weisen ein Muster unvollständiger Konvergenz für eine Reihe äußerer und innerer anatomischer Merkmale auf, was möglicherweise durch die relativ unterschiedliche Ökologie des Zwergameisenbären erklärt wird. Auf einer breiteren Säugetierskala konvergieren andere Merkmale, die möglicherweise mit der Ökologie der langsamen baumbewohnenden Lebensweise in einigen der untersuchten Taxa zusammenhängen, obwohl komplexe Muster auch durch andere evolutionäre Prozesse erklärt werden können. Nur suspensorisch lebende Taxa tragen signifikant zur Konvergenz bei. Diese Arbeit hebt die stärkere Konvergenz hervor, die sich in der inneren Struktur des Knochens widerspiegelt., Ecomorphological convergence occurs when similar morphological traits are independently evolved by species with the same lifestyle. Novel case studies can help to elucidate the underlying mechanisms of this process. This work addresses some convergent slow arboreal mammals, i.e. two lineages of ‘tree sloths’, the silky anteater, ‘Lorisidae’, two clades of extinct lemurs, i.e. palaeopropithecids and Megaladapis, and the koala. Functional morphological convergences are searched in these taxa, studying their humerus and femur as well as those of their closely related ecologically distinct taxa. For the first time, bones are analyzed at four anatomical levels, i.e. external shape, diaphyseal microstructure and anatomy and epiphyseal trabecular architecture, through phylogenetic comparative methods. Many slow arboreal mammals share a low cortical compactness, probably related to their extremely low metabolic rate and biomechanical demands. Slow arboreal xenarthrans, i.e. ‘tree sloths’ and the silky anteater, exhibit a pattern of incomplete convergence for a set of external and internal anatomical features, possibly explained by the relatively distinct ecology of the silky anteater. On a wider mammalian scale, other traits possibly related to slow arboreal ecology converge in some of the studied taxa, although with complex patterns also explained by other evolutionary processes. Only suspensory taxa significantly contribute to convergence. This thesis highlights the stronger convergence reflected by bone internal structure. By providing potential explanations for convergence in slow arboreal mammals, the inherent complexity of this process is here emphasized.

Identifying ecomorphological convergence examples is a central focus in evolutionary biology. In xenarthrans, slow arboreality independently arose at least three times, in the two genera of ‘tree sloths’, Bradypus and Choloepus, and the silky anteater, Cyclopes. This specialized locomotor ecology is expectedly reflected by distinctive morpho-functional convergences. Cyclopes, although sharing several ecological features with ‘tree sloths’, do not fully mirror the latter in their outstandingly similar suspensory slow arboreal locomotion. We hypothesized that the morphology of Cyclopes is closer to ‘tree sloths’ than to anteaters, but yet distinct, entailing that slow arboreal xenarthrans evolved through ‘incomplete’ convergence. In a multivariate trait space, slow arboreal xenarthrans are hence expected to depart from their sister taxa evolving toward the same area, but not showing extensive phenotypical overlap, due to the distinct position of Cyclopes. Conversely, a pattern of ‘complete’ convergence (i.e., widely overlapping morphologies) is hypothesized for ‘tree sloths’. Through phylogenetic comparative methods, we quantified humeral and femoral convergence in slow arboreal xenarthrans, including a sample of extant and extinct non-slow arboreal xenarthrans. Through 3D geometric morphometrics, cross-sectional properties (CSP) and trabecular architecture, we integratively quantified external shape, diaphyseal anatomy and internal epiphyseal structure. Several traits converged in slow arboreal xenarthrans, especially those pertaining to CSP. Phylomorphospaces and quantitative convergence analyses substantiated the expected patterns of ‘incomplete’ and ‘complete’ convergence for slow arboreal xenarthrans and ‘tree sloths’, respectively. This work, highlighting previously unidentified convergence patterns, emphasizes the value of an integrative multi-pronged quantitative approach to cope with complex mechanisms underlying ecomorphological convergence. Humboldt-Universität zu Berlin (1034)

Convergent evolution is a major topic in evolutionary biology. Low bone cortical compactness (CC, a measure of porosity of cortical bone) in the extant genera of “tree sloths,” has been linked to their convergent slow arboreal ecology. This proposed relationship of low CC with a slow arboreal lifestyle suggests potential convergent evolution of this trait in other slow arboreal mammals. Femoral and humeral CC were analyzed in “tree sloths,” lorisids, koala, and extinct palaeopropithecids and Megaladapis, in comparison to closely related but ecologically distinct taxa, in a phylogenetic framework. Low CC in “tree sloths” is unparalleled by any analyzed clade and the high CC in extinct sloths suggests the recent convergence of low CC in “tree sloths.” A tendency for low CC was found in Palaeopropithecus and Megaladapis. However, lorisids and the koala yielded unexpected CC patterns, preventing the recognition of a straightforward convergence of low CC in slow arboreal mammals. This study uncovers a complex relationship between CC and convergent evolution of slow arboreality, highlighting the multifactorial specificity of bone microstructure. Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659 Kickstarter Program from RTNN (NC, USA) Elsa‐Neumann‐Stipendium (Humboldt‐Universität zu Berlin)

Cortical compactness analysis in the humerus and the femur of slow arboreal mammals

AppendixS1:- Additional methods: potential cortical compactness (CC) biases deriving from CT spatial resolution and adjustements to the phylogenetic tree in order to fit the analysed sample- Additional results: detailed results for Stochastic Character Mapping (SCM) and Phylogenetic Generalized Least Square (PGLS) regressionsFigures S1-S5:Figure S1: Regions of interest (ROIs) selection criteria (aiming to limit subjectivity) are demonstratedFigure S2: Whole sample of humeral mid-shaft cross-sections with ROIsFigure S3: Whole sample of femoral mid-shaft cross-sections with ROIs Figure S4: Example of post-binarisation manual correction in order to remove pixels deriving from CT scanning noise from cortical vacuitiesFigure S5: Example of post-binarisation manual correction in order to remove pixels deriving from CT scanning noise around the periosteal regionanalysis code: R code used to perform the statistical analysisTableS1_humeri: Raw humeral CC and cortical area (CA) results including taxon, collection, specimen number, CT scan resolution, specimens on which post-binarisation corrections were performed (PostBinarCorr = ‘Yes’), specimens on which the cortex-spongiosa transition was manually delimited (SpongManualSel = ‘Yes'), specimens on which bony processes at the mid-shaft level were excluded (BoneProc= ‘Yes’), lifestyle and taxonomic categories (Taxon_for_Boxplots) used for data visualization- TableS2_femora: Raw femoral CC and cortical area (CA) results including taxon, collection, specimen number, CT scan resolution, specimens on which post-binarisation corrections were performed (PostBinarCorr = ‘Yes’), specimens on which the cortex-spongiosa transition was manually delimited (SpongManualSel = ‘Yes'), specimens on which bony processes at the mid-shaft level were excluded (BoneProc= ‘Yes’), lifestyle and taxonomic categories (Taxon_for_Boxplots) used for data visualization- time_tree: time calibrated tree used to phylogenetically inform the statistically analysis in NEXUS format - tips_lifestyle_states: slow arboreal (1) or non slow arboreal (0) states of the phylogenetic tree tips. These data are used for SCM.

In the next decades, the food policies, the management of agricultural system and the consumers’ customs will be influenced both by imminent food needs, such as the scarcity of protein foods, and by environmental issues, such as greenhouse gas emission, deforestation or sudden climate changes. Therefore, we are going towards a new food revolution with strong social and environmental bases (eco-sustainability policies, the overcame of intensive livestock, the reduction in animal-based food consumption, etc.). Consequently, the food technology sector can not be unprepared. It must quickly 'restructure' itself on the base of these new needs in order to provide immediate and efficient solutions. In this perspective, the present PhD thesis assessed the use of proteins from legumes (soybeans, chickpeas and grass pea) in the production of low cost and eco-sustainable ingredients for nutraceutical foods. Briefly, the PhD thesis achievements showed that proteins and peptides isolated from legumes have biological properties (i.e. antioxidant, antimicrobial and anti-hypertensive activities) able to increase both food quality and security. In addition, germination resulted to be a suitable method to produce legume ingredients that are highly nutritious and hypoallergenic.