Gregg F. Gunnell

Evolutionary history of bats : fossils, molecules and morphology

List of contributors Preface 1. Phylogenies, fossils and functional genes: the evolution of echolocation in bats Emma C. Teeling, Serena Dool and Mark Springer 2. Systematics and paleobiogeography of early bats Thierry Smith, Jorg Habersetzer, Nancy B. Simmons and Gregg F. Gunnell 3. Shoulder joint and inner ear of Tachypteron franzeni, an emballonurid bat from the middle Eocene of Messel Jorg Habersetzer, Evelyn Schlosser-Sturm, Gerhard Storch and Bernard Sige 4. Evolutionary history of the Neotropical Chiroptera: the fossil record Gary S. Morgan and Nicholas J. Czaplewski 5. New Basal Noctilionoid Bats (Mammalia: Chiroptera) from the Oligocene of Subtropical North America Nicholas J. Czaplewski and Gary S. Morgan 6. Necromantis Weithofer, 1887, large carnivorous middle and late Eocene bats from the French Quercy Phosphorites: new data and unresolved relationships Suzanne Hand, Bernard Sige and Elodie Maitre 7. African Vespertilionoidea (Chiroptera) and the antiquity of Myotinae Gregg F. Gunnell, Thomas P. Eiting and Elwyn L. Simons 8. Evolutionary and ecological correlates of population genetic structure in bats Kevin J. Olival 9. A bird? A plane? No, its a bat: an introduction to the biomechanics of bat flight Sharon M. Swartz, Jose Iriarte-Diaz, Daniel K. Riskin and Kenneth S. Breuer 10. Toward an integrative theory on the origin of bat flight Norberto P. Giannini 11. Molecular timescale of diversification of feeding strategy and morphology in New World Leaf-Nosed Bats (Phyllostomidae): a phylogenetic perspective Robert J. Baker, Olaf R. P. Bininda-Emonds, Hugo Mantilla-Meluk, Calvin A. Porter and Ronald A. Van Den Bussche 12. Why tribosphenic? On variation and constraint in developmental dynamics of chiropteran molars Ivan Horacek and Frantisek Spoutil 13. Necromantodonty, the primitive condition of lower molars among bats Bernard Sige, Elodie Maitre and Suzanne Hand 14. Echolocation, evo-devo, and the evolution of bat crania Scott C. Pedersen and Douglas W. Timm 15. Vertebral fusion in bats: phylogenetic patterns and functional relationships Dawn J. Larkey, Shannon L. Datwyler and Winston C. Lancaster 16. Early evolution of body size in bats Norberto P. Giannini, Gregg F. Gunnell, Jorg Habersetzer and Nancy B. Simmons Index.Advances in morphological and molecular methods continue to uncover new information on the origin and evolution of bats. Presenting some of the most remarkable discoveries and research involving living and fossil bats, this book explores their evolutionary history from a range of perspectives. Phylogenetic studies based on both molecular and morphological data have established a framework of evolutionary relationships that provides a context for understanding many aspects of bat biology and diversification. In addition to detailed studies of the relationships and diversification of bats, the topics covered include the mechanisms and evolution of powered flight, evolution and enhancement of echolocation, feeding ecology, population genetic structure, ontogeny and growth of facial form, functional morphology and evolution of body size. The book also examines the fossil history of bats from their beginnings over 50 million years ago to their diversification into one of the most globally widespread orders of mammals living today.

New Myzopodidae (Chiroptera) from the Late Paleogene of Egypt: Emended Family Diagnosis and Biogeographic Origins of Noctilionoidea

Myzopodidae is a family of bats today represented by two extant species of the genus Myzopoda that are restricted to the island of Madagascar. These bats possess uniquely derived adhesive pads on their thumbs and ankles that they use for clinging to smooth roosting surfaces. Only one fossil myzopodid has been reported previously, a humerus from Pleistocene deposits at Olduvai Gorge in Tanzania that was tentatively referred to the genus Myzopoda. Here we describe a new genus and two new species of myzopodids based on dental remains from Paleogene deposits in the Fayum Depression in Egypt, and provide an emended diagnosis for the family Myzopodidae. Phasmatonycteris phiomensis n. sp. is represented by four specimens from the early Oligocene Jebel Qatrani Formation and P. butleri n. sp. is known from a single specimen from the late Eocene Birket Qarun Formation. Together these specimens extend the temporal range of Myzopodidae by 36+ million years, and the geographic range by nearly 4000 kilometers. The new myzopodids, along with previously described bats from the Fayum and Australia, suggest that eastern Gondwana played a critical role in the origin and diversification of several bats clades notably including the superfamily Noctilionoidea, the majority of which live in the Neotropics today.

Giant lizards occupied herbivorous mammalian ecospace during the Paleogene greenhouse in Southeast Asia

Mammals dominate modern terrestrial herbivore ecosystems, whereas extant herbivorous reptiles are limited in diversity and body size. The evolution of reptile herbivory and its relationship to mammalian diversification is poorly understood with respect to climate and the roles of predation pressure and competition for food resources. Here, we describe a giant fossil acrodontan lizard recovered with a diverse mammal assemblage from the late middle Eocene Pondaung Formation of Myanmar, which provides a historical test of factors controlling body size in herbivorous squamates. We infer a predominately herbivorous feeding ecology for the new acrodontan based on dental anatomy, phylogenetic relationships and body size. Ranking body masses for Pondaung Formation vertebrates indicates that the lizard occupied a size niche among the larger herbivores and was larger than most carnivorous mammals. Paleotemperature estimates of Pondaung Formation environments based on the body size of the new lizard are approximately 2–5°C higher than modern. These results indicate that competitive exclusion and predation by mammals did not restrict body size evolution in these herbivorous squamates, and elevated temperatures relative to modern climates during the Paleogene greenhouse may have resulted in the evolution of gigantism through elevated poikilothermic metabolic rates and in response to increases in floral productivity.

Evolutionary History of Bats: Systematics and paleobiogeography of early bats

Introduction The phylogenetic and geographic origins of most extant mammalian orders are stilln poorly documented. Many first appear in the fossil record during then Paleocene-Eocene Thermal Maximum (PETM) at the beginning of the Eocene epochn about 55.5 million years ago (Smith et al ., 2006). However,n three prominent orders are exceptions to this pattern. Rodents first appeared inn North America about 0.5–1.0 million years before the PETM, but probablyn had an Asian origin like other Glires (Meng et al ., 2003). Batsn and whales are not known with any certainty before Middle Ypresian, about 54n mya. The earliest known bats are small, insectivorous forms that are preserved in bothn terrestrial and lacustrine fossil faunas. Their phylogenetic and geographicn origins are still unknown, although the absence of clear transitional forms inn the fossil record suggests that bat origins are potentially either quite ancientn or their evolution from non-volant mammals was quite rapid. Althoughn morphological evidence has generally supported an origin from withinn Euarchontoglires, sequence data from multiple genes strongly supports an originn of bats from within Laurasiatheria (Springer et al ., 2003;n Gunnell and Simmons, 2005). The oldest known fossil bats are early-middle Early Eocene taxa, and the firstn members of modern bat families and superfamilies seem to appear in the fossiln record in the Middle Eocene (Gunnell and Simmons, 2005). We thus here restrictn the term “early bats” to the species known from the Early andn early-middle Middle Eocene (Ypresian and Lutetian, and global equivalents,n encompassing European mammalian reference levels MP7 through MP13). These earlyn bats mainly include “eochiropterans” (Eochiroptera Van Valen 1979n is a controversial paraphyletic group composed of primitive taxa; see Simmonsn and Geisler, 1998 for an overview) and a few taxa belonging to the first membersn of modern families.

Quaternary Bat Diversity in the Dominican Republic

ABSTRACT The fossil record of bats is extensive in the Caribbean, but few fossils have previously been reported from the Dominican Republic. In this paper, we describe new collections of fossil bats from two flooded caves in the Dominican Republic, and summarize previous finds from the Island of Hispaniola. The new collections were evaluated in the context of extant and fossil faunas of the Greater Antilles to provide information on the evolution of the bat community of Hispaniola. Eleven species were identified within the new collections, including five mormoopids (Mormoops blainvillei, †Mormoops magna, Pteronotus macleayii, P. parnellii, and P. quadridens), five phyllostomids (Brachyphylla nana, Monophyllus redmani, Phyllonycteris poeyi, Erophylla bombifrons, and Phyllops falcatus), and one natalid (Chilonatalus micropus). All of these species today inhabitant Hispaniola with the exception of †Mormoops magna, an extinct species previously known only from the Quaternary of Cuba, and Pteronotus macleayii, which is currently known only from extant populations in Cuba and Jamaica, although Quaternary fossils have also been recovered in the Bahamas. Differences between the fossil faunas and those known from the island today suggest that dispersal and extirpation events, perhaps linked to climate change or stochastic events such as hurricanes, may have played roles in structuring the modern fauna of Hispaniola.

A New Early Eocene (Ypresian) Bat from Pourcy, Paris Basin, France, with Comments on Patterns of Diversity in the Earliest Chiropterans

A new early Eocene bat species is described from the Paris Basin locality of Pourcy (Marne), which is thought to represent either MP7 (early Ypresian; earliest Eocene) or MP8u2009+u20099 (middle Ypresian; later early Eocene) in the European Paleogene mammal chronostratigraphic scale. It is the first bat described from the Pourcy locality, and one of the world’s oldest chiropterans. The new bat shares a number of archaic dental features found in other early bats, but also exhibits several traits that appear derived and suggest referral to the family Onychonycteridae. Onychonycterids are restricted to the Ypresian of France, Belgium, England, and the USA, and include the most skeletally primitive of bats. Onychonycterids lived alongside bats that exhibit adaptations for more advanced flight capabilities but which had dentitions that were somewhat more similar to those of ancestral placental mammals. The new bat species from Pourcy, together with other Ypresian chiropterans, illustrates the mosaic nature of bat evolution in the early Eocene.

Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic condition are Adapis parisiensis with a reduced promontorial canal, and Rooneyia and Mahgarita with reduced stapedial canals.

Using Phylogenomic Data to Explore the Effects of Relaxed Clocks and Calibration Strategies on Divergence Time Estimation: Primates as a Test Case

Abstract Primates have long been a test case for the development of phylogenetic methods for divergence time estimation. Despite a large number of studies, however, the timing of origination of crown Primates relative to the Cretaceous‐Paleogene (K‐Pg) boundary and the timing of diversification of the main crown groups remain controversial. Here, we analysed a data set of 372 taxa (367 Primates and 5 outgroups, 3.4 million aligned base pairs) that includes nine primate genomes. We systematically explore the effect of different interpretations of fossil calibrations and molecular clock models on primate divergence time estimates. We find that even small differences in the construction of fossil calibrations can have a noticeable impact on estimated divergence times, especially for the oldest nodes in the tree. Notably, choice of molecular rate model (autocorrelated or independently distributed rates) has an especially strong effect on estimated times, with the independent rates model producing considerably more ancient age estimates for the deeper nodes in the phylogeny. We implement thermodynamic integration, combined with Gaussian quadrature, in the program MCMCTree, and use it to calculate Bayes factors for clock models. Bayesian model selection indicates that the autocorrelated rates model fits the primate data substantially better, and we conclude that time estimates under this model should be preferred. We show that for eight core nodes in the phylogeny, uncertainty in time estimates is close to the theoretical limit imposed by fossil uncertainties. Thus, these estimates are unlikely to be improved by collecting additional molecular sequence data. All analyses place the origin of Primates close to the K‐Pg boundary, either in the Cretaceous or straddling the boundary into the Palaeogene.

A new, large-bodied omnivorous bat (Noctilionoidea: Mystacinidae) reveals lost morphological and ecological diversity since the Miocene in New Zealand

A new genus and species of fossil bat is described from New Zealand’s only pre-Pleistocene Cenozoic terrestrial fauna, the early Miocene St Bathans Fauna of Central Otago, South Island. Bayesian total evidence phylogenetic analysis places this new Southern Hemisphere taxon among the burrowing bats (mystacinids) of New Zealand and Australia, although its lower dentition also resembles Africa’s endemic sucker-footed bats (myzopodids). As the first new bat genus to be added to New Zealand’s fauna in more than 150 years, it provides new insight into the original diversity of chiropterans in Australasia. It also underscores the significant decline in morphological diversity that has taken place in the highly distinctive, semi-terrestrial bat family Mystacinidae since the Miocene. This bat was relatively large, with an estimated body mass of ~40u2009g, and its dentition suggests it had an omnivorous diet. Its striking dental autapomorphies, including development of a large hypocone, signal a shift of diet compared with other mystacinids, and may provide evidence of an adaptive radiation in feeding strategy in this group of noctilionoid bats.

The challenges faced by living stock collections in the USA

Many discoveries in the life sciences have been made using material from living stock collections. These collections provide a uniform and stable supply of living organisms and related materials that enhance the reproducibility of research and minimize the need for repetitive calibration. While collections differ in many ways, they all require expertise in maintaining living organisms and good logistical systems for keeping track of stocks and fulfilling requests for specimens. Here, we review some of the contributions made by living stock collections to research across all branches of the tree of life, and outline the challenges they face. DOI: http://dx.doi.org/10.7554/eLife.24611.001