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1. SUBFOSSIL BIRDS AT VINTANY CAVE: A KEY TO UNDERSTANDING THE PAST ECOLOGY AND RECENT HISTORY OF TSIMANAMPESOTSE NATIONAL PARK

   Rasolonjatovo, HA M; Goodman, S M; Ranivoharimanana, L; Godfrey, L; Muldoon, KM (March 2024, NA)

   NA (Ed.)

   Madagascar, an island renowned for its rich biodiversity, is home to an impressive variety of bird species. The island’s Quaternary subfossil sites have yielded the remains of birds that bear testimony to an even richer avifauna during the recent past (Figure 1). These species are also excellent indicators of past habitats, due to habitat-specific adaptations (Behrensmeyer et al., 2003; Carrera et al., 2021). We studied the subfossil avifauna from Vintany Cave at Tsimanampesotse, SW Madagascar, to reconstruct the habitats of this region prior to human population expansion. The bird fossils were found in deposits alongside remains of other vertebrate species including large-bodied frugivorous lemurs, browsing elephant birds, and carnivorans such as Fossa fossana and Cryptoprocta spelea, the latter an extinct euplerid that preyed on large- bodied lemurs such as Pachylemur and Megaladapis. Radiocarbon dates establish an age range between 2000 and 3000 yr BP. 

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2. Subfossil birds from a submerged cave in southwestern Madagascar

   Rasolonjatovo, H.A M.; Muldoon, K.M.; Ranivoharimanana, L.; Rakotoarijaona, M.; Goodman, S. M. (December 2021, Malagasy nature)

   The Mahafaly karst of southwestern Madagascar is rich with subfossil deposits. Vintany Cave (also known as Aven Cave), a submerged cave at Tsimanampesotse National Park, is the most subfossil-dense submerged cave known in the world. In particular, the cave has yielded abundant remains of birds, including some that are extinct. Among 1077 bird specimens recovered under water from the cave floor and from excavated sediments at this site, 35 different taxa were identified. Taxonomic attributions were made through comparative morphological analysis, using comparative osteological museum collections. The majority of these species still occur inside the park. Five extinct taxa were recovered from the cave, including one species of elephant bird (Aepyornithidae, Mullerornis modestus), two species of giant endemic ground couas (Cuculidae, Coua cf. berthae and C. cf. primaeva), a shelduck (Alopochen sirabensis, Anatidae), and a lapwing (Charadriidae, Vanellus madagascariensis). Two extant taxa, Haliaeetus vociferoides (Accipitridae) and Threskiornis bernieri (Threskiornithidae) are locally extirpated, but exist at other localities in Madagascar. Remains of Greater Vasa Parrots (Psittaculidae, Coracopsis vasa) are predominant. Some of the identified extinct and locally extirpated taxa from Vintany Cave have an aquatic dependence, most specifically freshwater, that suggests that there has been environmental modification such as reduction of the important water sources in the region of Tsimanampesotse, and wetter conditions in the area in the past. 

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3. Teasing Apart Impacts of Human Activity and Regional Drought on Madagascar’s Large Vertebrate Fauna: Insights From New Excavations at Tsimanampesotse and Antsirafaly

   https://doi.org/10.3389/fevo.2021.742203  

   Godfrey, Laurie R.; Crowley, Brooke E.; Muldoon, Kathleen M.; Burns, Stephen J.; Scroxton, Nick; Klukkert, Zachary S.; Ranivoharimanana, Lovasoa; Alumbaugh, Jamie; Borths, Matthew; Dart, Ryan; et al (September 2021, Frontiers in Ecology and Evolution)

   Madagascar experienced a major faunal turnover near the end of the first millenium CE that particularly affected terrestrial, large-bodied vertebrate species. Teasing apart the relative impacts of people and climate on this event requires a focus on regional records with good chronological control. These records may document coeval changes in rainfall, faunal composition, and human activities. Here we present new paleontological and paleoclimatological data from southwestern Madagascar, the driest part of the island today. We collected over 1500 subfossil bones from deposits at a coastal site called Antsirafaly and from both flooded and dry cave deposits at Tsimanampesotse National Park. We built a chronology of Late Holocene changes in faunal assemblages based on 65 radiocarbon-dated specimens and subfossil associations. We collected stalagmites primarily within Tsimanampesotse but also at two additional locations in southern Madagascar. These provided information regarding hydroclimate variability over the past 120,000 years. Prior research has supported a primary role for drought (rather than humans) in triggering faunal turnover at Tsimanampesotse. This is based on evidence of: (1) a large freshwater ecosystem west of what is now the hypersaline Lake Tsimanampesotse, which supported freshwater mollusks and waterfowl (including animals that could not survive on resources offered by the hypersaline lake today); (2) abundant now-extinct terrestrial vertebrates; (3) regional decline or disappearance of certain tree species; and (4) scant local human presence. Our new data allow us to document the hydroclimate of the subarid southwest during the Holocene, as well as shifts in faunal composition (including local extirpations, large-vertebrate population collapse, and the appearance of introduced species). These records affirm that climate alone cannot have produced the observed vertebrate turnover in the southwest. Human activity, including the introduction of cattle, as well as associated changes in habitat exploitation, also played an important role. 

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4. The Tiny Skull of the Peruvian Gecko Pseudogonatodes barbouri (Gekkota: Sphaerodactylidae) Obtained via a Divide-And-Conquer Approach to Morphological Data Acquisition

   https://doi.org/10.2994/SAJH-D-17-00113.1  

   Bauer, Aaron M.; Beach-Mehrotra, Mallika; Bermudez, Yarima; Clark, Geneva E.; Daza, Juan D.; Glynne, Elizabeth; Hagyari, David; Harnden, Jennifer M.; Holovacs, Nicholas; Kanasiro, Andre; et al (August 2018, South American Journal of Herpetology)

   The Peruvian sphaerodactyl gecko, Pseudogonatodes barbouri, is among the smallest reptile species in South America. Morphological information about this species, or even the genus, is limited. In this study, we produced a bone-by-bone description from the skull and atlantoaxial complex to contribute new phenotypic information about this poorly known lizard. To achieve this objective, we employed a divide-and-conquer approach in which each author digitally isolated one or two bones from the skull and produced a written description of these elements, thereby reducing 3D imaging processing and description to a fraction of time. In addition to a reduced phalanx in the fourth toe of both the hand and foot, the genus is characterized by having nasal bones with a broad lateral wing, an ectopterygoid that clasps the pterygoid, and an anterior shifting of the paroccipital process and as consequence the position of the quadrate, and squamosal not participating in the quadrate suspension. There are also modifications in fenestration and foramina and a trend towards synostosis of the jaw bones (e.g., coronoid + splenial, compound bone + surangular). Pseudogonatodes bears four long processes on the intercentrum of the axis; which is a character of New World sphaerodactyls. 

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5. Description of the subfossil crocodylians from a new Late Pleistocene subfossil site (Tsaramody, Sambaina Basin) in central Madagascar

   Rakotozandry, R.; Ranivoharimanana, L.; Ranaivosoa, V.; Rasolofomanana, N.; Hekkala, E.; Samonds, K.E. (December 2021, Malagasy nature)

   Madagascar is famous today not only for its unique biodiversity, but also for the high levels of endemism of plants and animals. Less appreciated is the fact that, in the recent past, the island had even greater biodiversity with many other endemic animals such as giant lemurs, elephant birds, pygmy hippopotami, tortoises, and crocodiles that have gone extinct within the past 2000 years. The extinction of many of these groups is thought to be the result of both human activities and environmental change. Most research has focused on the lemurs, hippopotami, and elephant birds. Other recently extinct animals, including the Malagasy horned crocodile (Voay robustus), are relatively poorly known. Madagascar’s subfossil crocodylians include two taxa: the extinct V. robustus (the Malagasy horned crocodile) and the extant Crocodylus niloticus. The latter arrived on Madagascar relatively recently and we know little about the habitat preferences, distributions and ecological interactions (if any) of either species during the Holocene. In order to better understand the recent history of crocodylian extinction in Madagascar, we must first identify which species were present and where they were found. We present here a description of subfossil crocodylian material collected from the newly discovered subfossil site of Tsaramody (Sambaina Basin), a high-elevation wetlandenvironment. At 1655 m, it represents the highest elevation subfossil site on the island. Here we describe both cranial (e.g., premaxillary, jugal, and squamosal “horns”) and postcranial elements (e.g., osteoderms). Our research indicates that crocodile material from Tsaramody appears morphologically to belong to V. robustus, the extinct species. However, oval tuberosities on the frontal bone and a triangular extension of the squamosal bone suggest previously unrecognized variation. 

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