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Simple Summary: All life is derived from a single common ancestor, whose descendants coevolved with the planet, shaping the structure of biodiversity and the physical processes that operate on Earth. This complex history cannot be inferred solely by studying the genomes of living organisms, nor through analysis of the fossil remains of their extinct relatives. Only a unified approach integrating living and extinct species and drawing from both genomic and anatomical evidence can achieve this aim. In this review, we highlight recent advances, challenges, and opportunities in this endeavour. These include the development of models for analysis of anatomical data; methods for combined analysis of fossil and living species, as well as anatomical and genomic data; and the combined estimation of evolutionary relationships, geographic range, and evolutionary rates. However, the application of such methods is limited by a shortage of expertise in taxonomy and comparative anatomy, which are skills required for the compilation of anatomical datasets. Whereas there is a common concern for the incompleteness of the fossil record, knowledge with respect to the comparative anatomy of living species is equally incomplete. We anticipate that the increased demand for an integrative phylogenetic approach to reconstruct the tree of life and evolutionary patterns and processes will encourage researchers to overcome these challenges with the aim of elucidating the complexities behind organismal evolution across broad taxonomic and time scales. The modern era of analytical and quantitative palaeobiology has only just begun, integrating methods such as morphological and molecular phylogenetics and divergence time estimation, as well as phenotypic and molecular rates of evolution. Calibrating the tree of life to geological time is at the nexus of many disparate disciplines, from palaeontology to molecular systematics and from geochronology to comparative genomics. Creating an evolutionary time scale of the major events that shaped biodiversity is key to all of these fields and draws from each of them. Different methodological approaches and data employed in various disciplines have traditionally made collaborative research efforts difficult among these disciplines. However, the development of new methods is bridging the historical gap between fields, providing a holistic perspective on organismal evolutionary history, integrating all of the available evidence from living and fossil species. Because phylogenies with only extant taxa do not contain enough information to either calibrate the tree of life or fully infer macroevolutionary dynamics, phylogenies should preferably include both extant and extinct taxa, which can only be achieved through the inclusion of phenotypic data. This integrative phylogenetic approach provides ample and novel opportunities for evolutionary biologists to benefit from palaeontological data to help establish an evolutionary time scale and to test core macroevolutionary hypotheses about the drivers of biological diversification across various dimensions of organisms. [ABSTRACT FROM AUTHOR]

Spiny mice of the Acomys cahirinus group display a complex geographical structure in the Eastern Mediterranean area, as shown by previous genetic and chromosomal studies. To better elucidate the evolutionary relationships between insular populations from Crete and Cyprus and continental populations from North Africa and Cilicia in Turkey, genetic and morphometric variations were investigated, based on mitochondrial D-loop sequences, and the size and shape of the first upper molar. The Cypriot and the Cilician populations show idiosyncratic divergence in molar size and shape, while Cretan populations present a geographical structure with at least three differentiated subpopulations, as shown by congruent distributions of haplogroups, Robertsonian fusions and morphometric variation. A complex history of multiple introductions is probably responsible for this structure, and insular isolation coupled with habitat shift should have further promoted a pronounced and rapid morphological evolution in molar size and shape on Crete and Cyprus. [ABSTRACT FROM AUTHOR]

The house mouse (Mus musculus domesticus), as a successful invasive species worldwide, has to forage a variety of resources. Subantarctic mice display among the most notable diet shift from the usual omnivorous–granivorous diet, relying on a larger proportion of terrestrial animal prey. In agreement, a recent study of their mandible morphology evidenced an evolution of their mandible shape to optimize incisor biting and hence seize preys. Here, the incisors themselves are the focus of a morphometric analysis combined with a 3D study of their internal structure, aiming at a comparison between subantarctic populations (Guillou island, Kerguelen archipelago) with a range of western European continental, commensal mice. The predatory foraging behavior of Guillou mice was indeed associated with a sharper bevel of the lower incisor, which appears as an efficient morphology for piercing prey. The incisor of these mice also displays a reduced pulp cavity, suggesting slower eruption counterbalancing a reduced abrasion on such soft food material. The dynamics of the ever‐growing incisor may thus allow adaptive incisor sculpting and participate to the success of mice in foraging diverse resources. [ABSTRACT FROM AUTHOR]

While domestication has been well studied, with the recent recognition of the so-called 'domestication syndrome', the opposite process, feralization, has received far less attention. The commensal Western European house mouse (Mus musculus domesticus) lives in close contact with humans, and as such it lies between wild and domesticated animals. However, it also occurs in non-anthropogenic environments, forming feral populations, and hence provides the opportunity to document how feralization may impact morphology. In this study, three 'feral' populations from Orkney, the Kerguelen Archipelago and southern France were compared to Western European commensal populations. The shape and biomechanical properties of the jaw were analysed to assess the impacts of 'feralization' on an organ that is under major environmental pressures through its feeding function. Mandible shape varied mostly with climate and phylogeny, and feral populations differed only slightly from their geographically close relatives. In contrast, feral mice shared a biomechanical signature corresponding to a decrease in the superficial masseter/molar mechanical advantage, suggesting poorer molar biting performance. This is interpreted as a parallel response to a relaxation of environmental pressure, possibly due to a diet shift in feral habitats. [ABSTRACT FROM AUTHOR]

Abstract: Convergent evolution in similar environments constitutes strong evidence of adaptive evolution. Transported with people around the world, house mice colonized even remote areas, such as Sub‐Antarctic islands. There, they returned to a feral way of life, shifting towards a diet enriched in terrestrial macroinvertebrates. Here, we test the hypothesis that this triggered convergent evolution of the mandible, a morphological character involved in food consumption. Mandible shape from four Sub‐Antarctic islands was compared to phylogeny, tracing the history of colonization, and climatic conditions. Mandible shape was primarily influenced by phylogenetic history, thus discarding the hypothesis of convergent evolution. The biomechanical properties of the jaw were then investigated. Incisor in‐lever and temporalis out‐lever suggested an increase in the velocity of incisor biting, in agreement with observations on various carnivorous and insectivorous rodents. The mechanical advantage related to incisor biting also revealed an increased functional performance in Sub‐Antarctic populations, and appears to be an adaptation to catch prey more efficiently. The amount of change involved was larger than expected for a plastic response, suggesting microevolutionary processes were evolved. This study thus denotes some degree of adaptive convergent evolution related to changes in habitat‐related changes in dietary items in Sub‐Antarctic mice, but only regarding simple, functionally relevant aspects of mandible morphology. [ABSTRACT FROM AUTHOR]

Sustainable coexistence of similar, related species is generally expected to be achieved through character displacement, resulting in niche partitioning. The species Apodemus sylvaticus and Apodemus flavicollis are very similar both morphologically and ecologically, and have a large geographical overlap. Whether functional or biomechanical differences between these two species contribute to their coexistence remains unknown. A biomechanical model was created based on muscle data derived from dissections to estimate the maximum bite force. In addition, the dental microwear was analysed to test for evidence of a divergence in diet. Finally, geometric morphometric approaches were used to compare mandibular shapes. The results indicate that A. flavicollis, the slightly larger species, is optimized for biting at a larger gape angle. Apodemus sylvaticus appears to be slightly more specialized for grinding and biting at a narrower gape angle. However, the majority of shape variation in the mandible across both species follows the same pattern. No significant differences in microwear were observed between species, and thus, they appear to consume similar food types. These results suggest that character divergence resulting in niche partitioning has not occurred, possibly due to low resource competition. Alternatively, resource partitioning may occur through behavioural differences or differences in activity patterns. [ABSTRACT FROM AUTHOR]

The time scales of evolutionary and ecological studies tend to converge, as shown by evidences that contemporary evolution can occur as fast as ecological processes. This opens new questions regarding variation of characters usually considered to change mostly along an evolutionary time scale, such as morphometric traits, including osteological and dental features such as mandibles and teeth of mammals. Using two-dimensional geometric morphometric approach, we questioned whether such features can change on a seasonal and local basis, in relation to the ecological dynamics of the populations. Our model comprised populations of house mice ( Mus musculus domesticus ) in two contrasted situations in mainland Western Europe: a feral population vs. two close commensal populations. Mitochondrial DNA (D-loop) provided insight into the diversity and dynamics of the populations. The feral population appeared as genetically highly diversified, suggesting a possible functioning as a sink in relation to the surrounding commensal populations. In contrast, commensal populations were highly homogeneous from a genetic point of view, suggesting each population to be isolated. This triggered morphological differentiation between neighboring farms. Seasonal differences in morphometric traits (mandible size and shape and molar size and shape) were significant in both settings, although seasonal variations were greater in the feral than in the commensal population. Seasonal variations in molar size and shape could be attributed to differential wear in young or overwintered populations. Differences in mandible shape could be related to aging in overwintered animals, but also possibly to differing growth conditions depending on the season. The impact of these ecological processes on morphometric traits is moderate compared to divergence over a large biogeographic scale, but their significance nevertheless underlines that even morphological characters may trace populations dynamics at small scale in time and space. [ABSTRACT FROM AUTHOR]

Objectives Dental evolution affects the geometry of the tooth, but the adaptive relevance of these changes is related to tooth sharpness, complexity, and relief (topography). On a set of laboratory mice, we assessed how wear related to age and food consistency affected molar geometry and topography. Design Three groups of laboratory inbred mice (C57BL/6J strain) were considered: Four week old mice close to weaning, six month old mice fed on regular rodent pellets, and six month old mice fed on rodent pellets that were powdered and served as jelly. Their upper and lower molar rows were imaged in 3D. The geometry of the surfaces was quantified using a template describing the whole surface of the rows. Topographic indices were estimated on the same surfaces. Results The geometry of the molar rows was heavily affected by age-related wear. Food consistency affected mostly the upper molar row, which was more worn and less helical in soft food eaters. Tooth sharpness and relief decreased with age-related wear. Tooth relief was lower in soft food eaters, but only on the upper molar row. Tooth complexity was insensitive to wear. Conclusion The primary factor affecting tooth geometry and topography is age-related wear, as wear erodes the molar surfaces. Tooth complexity, however, appears to be insensitive to wear, making this index relevant for comparison of tooth morphology among wild mice of unknown age. Soft food eaters displayed more worn teeth, with less helical molar row occlusal surface, possibly because behavior and jaw morphology were disturbed due to this unusual food resource. [ABSTRACT FROM AUTHOR]

Geometric morphometrics aims to characterize of the geometry of complex traits. It is therefore by essence multivariate. The most popular methods to investigate patterns of differentiation in this context are (1) the Principal Component Analysis (PCA), which is an eigenvalue decomposition of the total variance-covariance matrix among all specimens; (2) the Canonical Variate Analysis (CVA, a.k.a. linear discriminant analysis (LDA) for more than two groups), which aims at separating the groups by maximizing the between-group to within-group variance ratio; (3) the between-group PCA (bgPCA) which investigates patterns of between-group variation, without standardizing by the within-group variance. Standardizing within-group variance, as performed in the CVA, distorts the relationships among groups, an effect that is particularly strong if the variance is similarly oriented in a comparable way in all groups. Such shared direction of main morphological variance may occur and have a biological meaning, for instance corresponding to the most frequent standing genetic variation in a population. Here we undertake a case study of the evolution of house mouse molar shape across various islands, based on the real dataset and simulations. We investigated how patterns of main variance influence the depiction of among-group differentiation according to the interpretation of the PCA, bgPCA and CVA. Without arguing about a method performing ‘better’ than another, it rather emerges that working on the total or between-group variance (PCA and bgPCA) will tend to put the focus on the role of direction of main variance as line of least resistance to evolution. Standardizing by the within-group variance (CVA), by dampening the expression of this line of least resistance, has the potential to reveal other relevant patterns of differentiation that may otherwise be blurred. [ABSTRACT FROM AUTHOR]

North Africa is an intricate biogeographical region at the crossroads of immigration waves from tropical Africa and Asia. Species confined between various barriers ( Atlas Mountains, arid environments such as the Sahara in the south, water masses such as the Mediterranean Sea in the north, and the Atlantic Ocean in the west) were generally forced to adapt locally to environmental changes instead of tracking their habitat by shifting their distribution area. The present study aims at providing first insight into the evolution of the genus Mus, and more specifically of the western Mediterranean species Mus spretus in this area. The study relies on the abundant Late Pleistocene and Middle Holocene fossil assemblage from the El Harhoura 2 cave ( Rabat- Témara, Morocco). This exceptional record was studied using geometric morphometrics applied to first upper and lower molars, constituting the most informative and best preserved fossil remains for such small rodents. Two main issues were addressed. (1) Geometric morphometrics was used to clarify taxonomic status and phylogenetic relationships among fossil and modern species in this area. Morphometric analysis revealed good discrimination of most modern and fossil species but failed to document intermediate forms tracing anagenetic evolution. Not mutually exclusive, the occurrence of complex processes of morphological evolution in this genus such as parallel evolution and the action of stabilizing selection may make it difficult to translate patterns of morphological evolution into phylogenetic conclusions. (2) The record was shown to document a sequence of intraspecific evolution of M. spretus. The morphology of the molars through the fossil record of El Harhoura 2 was surprisingly stable despite extensive modern variation. The limited temporal variation largely failed to correlate to palaeoenvironmental proxies. The mouse fossil record at El Harhoura 2 thus presents an intriguing case of morphological stasis despite extensive environmental changes. This long-term stability may have been recently perturbed by anthropogenic factors including landscape changes and introduction of various competitors and predators, leading to a size reduction. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109, 599-621. [ABSTRACT FROM AUTHOR]

Recognition of evolutionary units (species, populations) requires integrating several kinds of data, such as genetic or phenotypic markers or spatial information in order to get a comprehensive view concerning the differentiation of the units. We propose a statistical model with a double original advantage: (i) it incorporates information about the spatial distribution of the samples, with the aim to increase inference power and to relate more explicitly observed patterns to geography and (ii) it allows one to analyze genetic and phenotypic data within a unified model and inference framework, thus opening the way to robust comparisons between markers and possibly combined analyses. We show from simulated data as well as real data that our method estimates parameters accurately and is an improvement over alternative approaches in many situations. The power of this method is exemplified using an intricate case of inter- and intraspecies differentiation based on an original data set of georeferenced genetic and morphometric markers obtained on Myodes voles from Sweden. A computer program is made available as an extension of the R package Geneland. [ABSTRACT FROM AUTHOR]

Past climatic fluctuations influenced forest habitats and impacted heavily the distribution of forest species, such as the edible dormouse, by changing the distribution and composition of forests themselves. Such effects may be valid for ongoing climate change as well. To improve our understanding of the edible dormouse's history and how it responded to changes in its environment, we investigated its variation across the understudied zone of Northern Turkey using two complementary markers of differentiation: the mitochondrial cytochrome b gene for genetics, and size and shape of the first upper molar for phenotypic differences. Genetic and morphometric results were strongly discrepant. Genetic analyses evidenced an amazing homogeneity throughout the Eurasian range of the edible dormouse, whereas morphometrics pointed to a complex, step-wise differentiation along the Black Sea coast, the main signal being an opposition between Easternmost and Westernmost Turkish dormice. The genetic homogeneity suggests that this phenotypic differentiation is not the inheritance of glacial refuges, but the consequence of a more recent post-glacial isolation. The transition between the European and Asian groups is located eastwards from the Marmara straits, undermining its claimed role as an efficient barrier but stressing the importance of climatic and vegetational factors. A secondary differentiation between populations from the Central Black Sea coast and Easternmost regions was evidenced, attributed to a complex interplay of climatic, topographic, anthropogenic, and ecological factors. Turkey, at the crossroad of European and Asian species, heavily impacted by the current global change including climatic and anthropogenic factors, appears of importance for understanding the historical dynamics of differentiation and exchanges between populations that shaped the current distribution of Eurasian species and their future survival. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ••, ••-••. [ABSTRACT FROM AUTHOR]

Variation within a population is a key feature in evolution, because it can increase or impede response to selection, depending on whether or not the intrapopulational variance is correlated to the change under selection. Hence, main directions of genetic variance have been proposed to constitute "lines of least resistance to evolution" along which evolution would be facilitated. Yet, the screening of selection occurs at the phenotypic level, and the phenotypic variance is not only the product of the underlying genetic variance, but also of developmental processes. It is thus a key issue for interpreting short and long term evolutionary patterns to identify whether main directions of phenotypic variance indeed constitute direction of facilitated evolution, and whether this is favored by developmental processes preferably generating certain phenotypes. We tackled these questions by a morphometric quantification of the directions of variance, compared to the direction of evolution of the first upper and lower molars of wild continental and insular house mice. The main phenotypic variance indeed appeared as channeling evolution between populations. The upper molar emerged as highly evolvable, because a strong allometric component contributed to its variance. This allometric relationship drove a repeated but independent evolution of a peculiar upper molar shape whenever size increased. This repeated evolution, together with knowledge about the molar development, suggest that the main direction of phenotypic variance correspond here to a "line of least developmental resistance" along which evolution between population is channeled. [ABSTRACT FROM AUTHOR]

Abstract: Conodonts are an extinct group of organisms, known from the Upper Cambrian to the Triassic. They have no extant representatives, and tooth-like buccal elements are usually the only remains of the animal found in the sediments. Therefore, most of their taxonomy rests on these elements that are good stratigraphic tools for these ancient periods, due to their rapid morphological evolution. Conodont species are usually described species that are based on either clusters of elements corresponding to an entire apparatus (natural assemblages), or on the most frequently preserved element. These described species are acceptable stratigraphic tools, but hardly consider the dimension of the variation that a biological species can encompass through time and space. In order to tackle temporal, environmental and biogeographical changes, recent studies have shown that morphological variation should be taken into account by quantitative analyses, aiming at getting at the closest of what the former species might have been. [Copyright &y& Elsevier]

Is the ability to respond to minor perturbations a key to survival to major crisis? This idea was supported by previous studies on Late Devonian conodonts. Genera surviving the Frasnian/Famennian (F/F) crisis, at the end of the Upper Kellwasser anoxic event, had shown a response to a similar but minor event, the Lower Kellwasser (LKW). In contrast, the genus Ancyrodella went extinct at the F/F crisis. This study aims to assess whether this extinction was associated with the absence of response to the minor LKW event. For this purpose, the shape of the P1 platform elements of the conodont Ancyrodella curvata was quantified based on their 2-D outlines. Conodonts were extracted from two outcrops documenting the Late Devonian Kellwasser events, Coumiac (France) and Mrirt (Morocco). Ancyrodella curvata is characterized by a marked allometric growth that may blur any other source of shape difference, like response to the LKW. Hence, a multivariate method was developed to disentangle size-free from size-related shape variations. No coherent temporal size variations emerged from the analysis, but allometry occurring along the growth of the element indeed appeared as the prevailing source of shape variation. By isolating size-free variations, however, we were able to evidence a morphometric response of A. curvata to the LKW independent from the allometric pattern. Hence, the extinction of A. curvata at the F/F crisis cannot be attributed to an absence of response to minor events. The amount of shape change involved in the LKW shift is, however, of minor importance in comparison with the shape variation due to allometric growth. Alternate hypotheses have been further investigated. Ancyrodella curvata appears as a rare species in the assemblages, and its distribution worldwide suggests a rather specialist taxon. Considering survivorship curves (i.e. frequency distribution of the conodont as a function of its size) A. curvata was characterized by low and constant mortality rate. This may be a clue for a long growth and progressive investment in the reproduction. These arguments support the view that A. curvata was a rather specialist, rare and ‘K-selected’ taxon. All these factors may not be exclusive and their unfavourable conjunction might have been the key to the extinction of A. curvata. [ABSTRACT FROM AUTHOR]

Abstract: We present the trends of absolute conodont abundance, relative genera abundance, and conodont morphometrics across the Late Devonian Kellwasser horizons at three northern Gondwanan epicontinental seaway locations. At three contrasting depositional settings, the Kellwasser events are characterized by a decrease in conodont abundance, high percentage of the conodont genus Icriodus and morphological change of the conodont genus Palmatolepis. These changes can be identified in sections where the events are expressed as interbedded anoxic and oxic deposits as well as in settings characterized by continuous anoxic sediment accumulation. Hence, these changes are interpreted as global and synchronous and can be thus used for event correlation. The paradox of these results is that despite quite similar isotopic signals, faunal change during the Lower Kellwasser event was less than during the Upper Kellwasser event. We interpret that this discrepancy is due to an unconformity (including topmost Frasnian to earliest Famennian) at several F/F sections which removed the record of peak paleoenvironmental change. [Copyright &y& Elsevier]

The lava mouseMalpaisomyswas part of Pleistocene and Holocene faunas of the eastern Canary Islands; it became extinct during historical times. In order to evaluate the evolutionary processes of this endemic species, we set out to identify its relationships with possible mainland relatives. Its dental morphology was compared to a set of fossil and modern murine rodents from various phylogenetic groups, characterized by different diets and dental patterns, using a quantitative method based on a Fourier analysis of the outline of the first upper and lower molars. This morphometric analysis identified different evolutionary grades that are independent of the phylogenetic group. The first cluster is associated with primitive, asymmetric dental outlines, the second with intermediate forms linked to a more herbivorous diet. Highly differentiated forms diverge not only from the second cluster but also from each other. Our investigations revealMalpaisomysto have had an intermediate dental pattern, a result which confirms previous palaeoecological interpretations of this taxon. However, conclusions about its closest mainland relative remain tentative. Based on a comparison of dental size and shape, as well as geographical considerations, a possible mainland ancestor could be eitherParaethomys(North-African Pliocene) orOccitanomys(South-western European Pliocene). Such results support the hypothesis of a Pliocene colonization event, in which caseMalpaisomyswould display a normal evolutionary rate in dental size and shape, in spite of the insular context. In contrast, a late colonization by a modern representative of the African fauna would imply exceptionally high evolutionary rates compared to the background morphological evolution and a decrease in size that is unlikely under insular conditions. © 2004 The Linnean Society of London,Zoological Journal of the Linnean Society, 2004,142, 555–572. [ABSTRACT FROM AUTHOR]

The size of any organism is influenced by the surrounding ecological conditions. In this study, we investigate the effects of such factors on the size spectra of planktic foraminiferal assemblages from Holocene surface sediments. We analyzed assemblages from 69 Holocene samples, which cover the major physical and chemical gradients of the oceans. On a global scale, the range of sizes in assemblages triples from the poles to the tropics. This general temperature-related size increase is interrupted by smaller sizes at temperatures characteristic of the polar and subtropical fronts, at 2°C and 17°C, respectively, as well as in upwelling areas. On a regional scale, surface water stratification, seasonality and primary productivity are highly correlated with the size patterns. Such environmentally controlled size changes are not only characteristic for entire assemblage, but also for the dominant single species. [Copyright &y& Elsevier]

Morphological variability of the planktic foraminifer Globorotalia truncatulinoides, estimated by size, shape, and coiling direction of the test, has been studied throughout the last 140 kyr in three cores in the South Atlantic. The biogeographic component of the morphological variation has been identified as difference between the three cores, located in the subantarctic frontal system, the equatorial upwelling zone, and the northern margin of the subtropical gyre. Temporal variability of morphology has been quantified and compared to biogeographic morphological variations, and paleoenvironmental proxies. The most important morphological differentiation is related to biogeography. Size and shape vary according to a temperature gradient across the different cores. This pattern is likely the result of differences between the four cryptic genetic species that have been previously identified within the taxon, and that are associated with different ecological preferences. Temporal variations can be recognized within each of the three cores, even in the most stable situation of the subtropical gyre. Significant correlations emerge between morphology and paleoenvironmental proxies, suggesting that the morphological variations are a response to environmental change. The same shape–temperature relationship emerges from both, biogeographic differences and local temporal variations. This suggests that the complex of species G. truncatulinoides mainly reacted to the glacial–interglacial climatic fluctuations of the last 140 kyr by a process of habitat tracking, i.e. the different species shifted their geographic distribution without major modifications of their ecological preferences. Yet, evolution may be involved as a response to environmental changes on a longer time scale. [Copyright &y& Elsevier]

Recent extensive field prospecting conducted in the Upper Miocene of Lebanon resulted in the discovery of several new fossiliferous localities. One of these, situated in the Zahleh area (Bekaa Valley, central Lebanon) has yielded a particularly diverse vertebrate fauna. Micromammals constitute an important part of this assemblage because not only do they represent the first Neogene rodents and insectivores from Lebanon, but they are also the only ones from the early Late Miocene of the Arabian Peninsula and circumambient areas. Analyses of the murines from Zahleh reveal that they belong to a small-sized early Progonomys, which cannot be assigned to any of the species of the genus hitherto described. They are, thereby, shown to represent a new species: Progonomys manolo. Morphometric analyses of the outline of the first upper molars of this species suggest a generalist and omnivorous diet. This record sheds new light onto a major phenomenon in the evolutionary history of rodents, which is the earliest dispersal of mice. It suggests that the arrival of murines in Africa got under way through the Levant rather than via southern Europe and was monitored by the ecological requirements of Progonomys. [ABSTRACT FROM AUTHOR]