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Kelba quadeemae , a fossil mammal from the Early Miocene of East Africa, was originally named on the basis of three isolated upper molars. Kelba has previously been interpreted as a creodont, a pantolestid, an insectivoran, and a hemigaline viverrid. The true affinities of this taxon have remained unclear because of the limited material and its unique morphology relative to other Miocene African mammals. New material of Kelba from several East African Miocene localities, most notably a skull from the Early Miocene locality of Songhor in Western Kenya, permits analysis of the affinities of Kelba and documents the lower dentition of this taxon. Morphological comparison of this new material clearly demonstrates that Kelba is a member of the order Ptolemaiida, a poorly understood group whose fossil record was previously restricted to the Oligocene Fayum deposits of northern Egypt. Phylogenetic analysis supports the monophyly of the Ptolemaiida, including Kelba , and recovers two monophyletic clades within the order. We provide new family names for these groups and an emended diagnosis for the order. The discovery of ptolemaiidans from the Miocene of East Africa is significant because it extends the known temporal range of the order by >10 million years and the geographic range by >3,200 km. Although the higher-level affinities of the Ptolemaiida remain obscure, their unique morphology and distribution through a larger area of Africa (and exclusively Africa) lend support to the idea that Ptolemaiida may have an ancient African origin.

The evolution of cursorial adaptations in Tertiary (65-1.65 Myr ago) carnivores has been a contentious issue. Most such studies have focused on the relationship between hind limb proportions and running speed. Here, we show morphometrically that in extant carnivores, the elbow joint has evolved in two distinct directions with mutually exclusive implications for locomotor ability and prey procurement. Some carnivores retain supinatory ability, allowing them to manipulate prey and other items with the forepaws. Such carnivores can become very large. Other carnivores lose the ability to supinate and become cursors. This allows for only moderate size increase. Modern carnivores above ca. 20 kg body mass are committed to one or other of these strategies. This threshold coincides with a postulated threshold in carnivore physiology. The biaxial pattern mostly follows phylogenetic lines, but a strong selective regime can override this signal, as shown by the extant cheetah. Oligocene (33.7-23.8 Myr ago) and early-middle Miocene (23.8-11.2 Myr ago) carnivores follow the same pattern, though in the Miocene the pattern is shifted towards larger body mass, which may be owing to the extraordinary richness of browsing ungulates at this time.

One may be forgiven for believing, on the basis of the title, that this book is similar in content and intent to some other recent major compilations of continent-wide mammalian fossil records, suc...

The adaptive significance of the scrotum and the evolution of the descent of the testicles and epididymis have been a focus of interest among biologists for a long time. In this paper we use three anatomical character states of the scrotum and descensus: (1) testicles descended and scrotal; (2) testicles descended but ascrotal; (3) testicles not descended (testicondy). These states are then mapped on an up to date phylogeny of the Mammalia. Three main points arise out of this mapping procedure: (1) the presence of a scrotum is either primitive in extant Mammalia or primitive within eutherian mammals except Insectivora; (2) evolution has generally proceeded from a scrotal condition to progressively more ascrotal; (3) loss of testicular descensus is less common in mammalian evolution than is loss of the scrotum. In the light of these findings we discuss some current hypotheses regarding the origin and evolution of the scrotum. We find that these are all incomplete in so far as it is not the presence of the scrotum in various mammal groups that requires explaining. Instead, it is the reverse process, why the scrotum has been lost in so many groups, that should be explained. We suggest that the scrotum may have evolved before the origin of mammals, in concert with the evolution of endothermy in the mammalian lineage, and that the scrotum has been lost in many groups because descensus in many respects is a costly process that will be lost in mammal lineages as soon as an alternative solution to the problem of the temperature sensitivity of spermatogenesis is available.

A classic question in evolutionary biology concerns the tempo and mode of lineage evolution. Considered variously in relation to resource utilization, intrinsic constraints or hierarchic level, the question of how evolutionary change occurs in general has continued to draw the attention of the field for over a century and a half. Here we use the largest species-level phylogeny of Coenozoic fossil mammals (1031 species) ever assembled and their body size estimates, to show that body size and taxonomic diversification rates declined from the origin of placentals towards the present, and very probably correlate to each other. These findings suggest that morphological and taxic diversifications of mammals occurred hierarchically, with major shifts in body size coinciding with the birth of large clades, followed by taxonomic diversification within these newly formed clades. As the clades expanded, rates of taxonomic diversification proceeded independently of phenotypic evolution. Such a dynamic is consistent with the idea, central to the Modern Synthesis, that mammals radiated adaptively, with the filling of adaptive zones following the radiation.

Palmqvist (2002) has criticized our attribution of the mandibular ramus of Megantereon from South Turkwel, Turkana Basin, Kenya, to a new species, M. ekidoit (Werdelin and Lewis, 2000), suggesting instead that it “unequivocally” belongs to the African species M. whitei . We believe that this criticism stems from a misunderstanding of our statements and from an erroneous view of variability within Megantereon . In this reply we shall address Palmqvist's criticisms, showing that M. ekidoit is not synonymous with M. whitei , and also that the specific attribution of various Megantereon specimens is not as clear cut as Palmqvist (2002; Martinez Navarro and Palmqvist, 1995, 1996) believes. Palmqvist (2002) begins with a brief introduction to the current state of knowledge of Megantereon taxonomy and evolution, whilst criticizing us for not providing the same. Our reasons for not doing so are that our paper was on the South Turkwel fauna as a whole, not on Megantereon , and that a separate paper focusing on Megantereon by one of us (LW) is nearly complete. This second paper will naturally include all the relevant references to previous work. In the next section Palmqvist carries out a quantitative analysis of the mandibular dentition of Megantereon . The result of this analysis is that the p4 and m1 of M. ekidoit do not differ metrically from the homologous teeth in M. whitei . We completely agree with this analysis, and have never claimed that they were different. Indeed, dental characters are conspicuously absent from our diagnosis of M. ekidoit . However, while we agree with Palmqvist regarding the results of this quantitative dental analysis, we strongly disagree with its implied corollary, namely that a difference in dental metrics is required for two forms to be different species. This must be Palmqvist's unstated claim, …

Allometry in the placoderm Bothriolepis canadensis and its significance to antiarch evolution

The borophagine canids were bone-cracking scavengers in the Miocene-Pleistocene of North America. In this they parallel the Recent hyenas. This paper analyzes the borophagine adaptation in relation to that of hyaenids, using Osteoborus cyonoides as an example. The emphasis during canid evolution on the posterior molars, which is a derived condition, created a constraint on the adaptation of borophagines. This constraint meant that the borophagines used P4/4 as bone-cracking teeth, whereas hyaenids use P3/3. The latter adaptation has the advantage of separating the bone-cracking teeth from the meat-cutting portion of the dentition, thereby allowing a dual purpose dentition in hyaenids. In borophagines, no such dual purpose was possible, and it is suggested that they were closer to obligate bone-cracking scavengers than Recent hyaenids. Other than the evolution of a specialized bone-cracking tooth, the borophagines adapted to bone cracking by evolving a vaulted and strengthened skull for the dissipation of the strong forces generated during bone cracking. In this they again parallel the hyaenids. Evolution within borophagines involved an elaboration of patterns already set at the group's inception, creating an evolutionary trend which was mediated by the constraint on the bone-cracking morphology. This trend may be due to selection or sorting, or may, under certain assumptions, be stochastic. Other evolutionary trends may also be epiphenomena of constraints that lock morphological evolution.

A new species of bothriolepid antiarch, Bothriolepis tatongensis sp. nov., from the Late Devonian basal conglomerate of the Hollands Creek Rhyodacite, near Tatong, northern Victoria, is described. B. tatongensis sp. nov. can be distinguished from all other species possessing a trifid preorbital recess by the short postpineal plate with paired pits opening anteriorly into the orbital fenestra, and by coarsely reticulate dermal ornament. B. gippslandiensis Hills, B. cullodenensis Long, B. fergusoni Long, B. bindareei Long and B. warreni Long are described and illustrated. Metric analysis of headshield and premedian plate measurements of B. gippslandiensis, B. cullodenensis and B. fergusoni are compared with ontogenetic variation in B. canadensis Whiteaves. The phylogenetic position of B. fergusoni and B. tatongensis sp. nov. is discussed and the significance of the preorbital recess in bothriolepid evolution re-evaluated. A trifid preorbital recess is suggested to be apomorphic within the Bothriolepidoidei ...

Fossil finds of the hyaenid genus Chasmaporthetes are reviewed. We consider the characters distinguishing this genus from Euryboas invalid and synonymize the two genera. The following species are included within the genus Chasmaporthetes: C. borissiaki (Khomenko), C. lunensis (Del Campana), with two subspecies, C. l. lunensis, from Europe, and C. l. honanensis, from China, C. nitidula (Ewer), C. ossifragus Hay, with two subspecies, C. o. ossifragus from the western United States, and C. ossifragus, an unnamed new subspecies from Florida, and C. exitelus, a new species from the Turolian of China. The presence of sexual dimorphism in C. lunensis is indicated from canine size. The stratigraphie range of the genus is early Blancan-Irvingtonian (North America), Turolian-Villa-franchian (Eurasia), Langebaanian to lower Pleistocene (Africa). The possible relationships of Chasmaporthetes are considered, and it is concluded that the genus is most closely related to the genus Thalassictis.

Studies of fossil hyaenas: the genera Thalassictis Gervais ex Nordmann, Palhyaena Gervais, Hyaenictitherium Kretzoi, Lycyaena Hensel, and Palinhyaena Qiu, Huang and Guo

This paper summarizes the currently available fossil record of small felines in North America. Felis amnicola Gillette is shown by statistical methods to be conspecific with F. wiedii and is proposed as a subspecies F. wiedii amnicola. Pre-Wisconsinan specimens of Lynx rufus are brought together as L. rufus calcaratus. The occurrence of F. yagouaroundi in post-Hemphillian deposits of North America is doubtful and most of the currently accepted records are reassigned to F. amnicola. F. lacustris and F. rexroadensis are shown to be distinct species, but it is difficult to assign individual specimens to species. L. issiodorensis kurteni is considered a junior synonym of F. rexroadensis. F. lacustris and F. rexroadensis have limb proportions that approach those of L. issiodorensis.

A method for identifying ecophenotypic variants is tested, using two morphological variants of the benthic foraminifer Reophax dentaliniformis Brady from the Baltic Sea. Results show that the example does not correspond to the model for ecophenotypic variation. This is interpreted as showing that the two forms are genetically differentiated and that the gene flow between them is restricted by the water circulation pattern in the Baltic.

Supernumerary dental elements have been reported in Lynx lynx by several authors. These features have been given different evolutionary interpretations by different commentators. I note here that, since these features are absent in the plesiomorphic sister-groups of L. lynx, they represent a true evolutionary reversal. If they were simply a retention of an evolutionarily older phenotype, we should expect to see them developed in at least one plesiomorphic sister-group. Such development of a previously hidden character can occur if it is genetically linked to features selected for, until it becomes phenotypically expressed, whereupon selection can act on the character itself. Since Dollo's law, which is the theoretical issue behind the present discussion, is not a law, but a rule, and, like all rules based on probabilities, we should expect to find exceptions in the fossil record. Such exceptions are not rare, but few are as spectacular as the present one, in which the redeveloped feature is at least phenotypically identical with one which has been lost in the Felidae since the Miocene.

In both jaw geometry and molar morphology, eutherian carnivores (order Carnivora) as a whole display greater diversity (plasticity in evolution from the primitive type) than marsupial carnivores (order Dasyurida). This is related to the difference in tooth replacement between the two taxa. In Carnivora, the permanent carnassial is preceded by a deciduous carnassial; the permanent tooth can erupt in its (geometrically) permanent position, and the post-carnassial molars are free to evolve for specialized functions or be reduced. In Dasyurida, there is relative molar progression, each erupting molar in turn functioning as a carnassial, and subsequently being pushed forwards in the jaw by the next erupting molar. Thus, all molars have carnassiform morphology, and none are free to develop for other functions. The greater plasticity of Carnivora has led to their adaptive zone being broader (as a group they are relatively more eurytopic than Dasyurida), which in turn has led to greater taxonomic diversity within Carnivora than Dasyurida. The resulting pattern from a macroevolutionary point of view is that, even in the absence of direct competition, Carnivora have had greater evolutionary “success” than Dasyurida.

A new species of chimaeroid, Harriotta lehmani, is described. It differs from Recent species of Harriotta in the shape of the paired rostral cartilages and second dorsal fin. This is the first record of a chimaeroid from the Cretaceous fish-beds of Lebanon, as well as being the first fossil representative of the genus Harriotta.

de Muizon, C. 1988: Les Vertebres Fossiles de la Formation Pisco (Perou) III. Les Odontocetes (Cetacea, Mammalia) du Miocene. 244 pp. Institut Fran¸ais d'etudes Andines et Institut de Paleon-tologie du Museum National d'Histoire Naturelle. editions Recherche sur les Civilisations, A.D.P.F., Paris. ISBN 2–86538–187–0, ISSN 0291–1655. Price: 289.00 FF (paper).

A set of 11 measurements on 40 species of placental (Order Carnivora) and marsupial (Order Dasyurida) carnivores is analysed by means of correspondence analysis. Dasyurida have long mandibles and tooth rows, large muscle attachment areas on the mandible, long moment arms of the temporalis and masseter, and a low occiput and short temporal fossa. Skull shape is uniform in Dasyurida, with about the same variability as in a family of Carnivora. The temporalis of Dasyurida is relatively small, but this may be compensated for by the more rounded shape and longer moment arm. The Tasmanian tiger, Thylacinus cynocephalus, is more similar in skull shape to the red fox, Vulpes vulpes, than to the placental wolf, Canis lupus. The M5 of Dasyurida occupies the same geometric position as the MI in Carnivora, providing a possible explanation for the greater variability in cheek teeth in Carnivora. The Tasmanian devil, Sarcophilus harrisii, is similar to the Hyaenidae in having a shorter distance between the ultimate sectorial molar and the condyle. It is suggested that this is an adaptation to cracking open bones, as this mandible geometry brings the main bone-cracking teeth closer to the region of greatest muscle force.

Kurten, B. 1988: On Evolution and Fossil Mammals. XVII + 301 pp. Columbia University Press. ISBN 0–231–05868–3. Price: USD40.00 (bound).

Marsupial carnivores of the order Dasyurida are more uniform in molar morphology and jaw geometry than are their placental counterparts. This difference is related to the difference in tooth replacement between marsupials and placentals. In Carnivora, the permanent carnassial can erupt in its (geometrically) permanent position, and the post-carnassial teeth are free to evolve in various ways. In the Dasyurida, each erupting molar in turn functions as carnassial before being pushed forwards (relatively) in the jaw by the next erupting molar, which in turn becomes the carnassial. Thus, in the Dasyurida, all molars come to have carnassiform morphology. One group of Australian fossil carnivores has avoided this constraint: the Thylacoleonidae, 'marsupial lions'. In this group, P3/3 are the teeth functioning as carnassials, having been coopted for this function from the presumed sectorial P3/3 of the herbivorous ancestors of Thylacoleonidae. This has made molar reduction possible in this group, but has brought about some incidental effects. P3/3 lie far forward in the jaw, and the muscle resultant has been shifted forwards to compensate for this, reducing gape, but increasing bite force at I1/1, teeth which function as canines in Thylacoleonidae.

Background: Understanding the demographic history of a population is critical to conservation and to our broader understanding of evolutionary processes. For many tropical large mammals, however, this aim is confounded by the absence of fossil material and by the misleading signal obtained from genetic data of recently fragmented and isolated populations. This is particularly true for the lion which as a consequence of millennia of human persecution, has large gaps in its natural distribution and several recently extinct populations. Results: We sequenced mitochondrial DNA from museum-preserved individuals, including the extinct Barbary lion (Panthera leo leo) and Iranian lion (P. l. persica), as well as lions from West and Central Africa. We added these to a broader sample of lion sequences, resulting in a data set spanning the historical range of lions. Our Bayesian phylogeographical analyses provide evidence for highly supported, reciprocally monophyletic lion clades. Using a molecular clock, we estimated that recent lion lineages began to diverge in the Late Pleistocene. Expanding equatorial rainforest probably separated lions in South and East Africa from other populations. West African lions then expanded into Central Africa during periods of rainforest contraction. Lastly, we found evidence of two separate incursions into Asia from North Africa, first into India and later into the Middle East. Conclusions: We have identified deep, well-supported splits within the mitochondrial phylogeny of African lions, arguing for recognition of some regional populations as worthy of independent conservation. More morphological and nuclear DNA data are now needed to test these subdivisions. European Union�s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. FP7-PEOPLE-2011-IEF-298820. Scopus