Micromammal assemblages offer valuable insights into local palaeoenvironmental conditions and contribute to refining biochronological frameworks in the Cradle of Humankind (CoH), South Africa. This study presents the taxonomic, taphonomic, and palaeoecological analysis of micromammalian remains recovered from newly excavated in situ deposits at the Gondolin GD2 locality. A total of 372 cranio-dental elements representing at least 124 individuals were identified, comprising 19 taxa across five mammalian orders. Rodents dominate the assemblage (approximate to 78% of MNI), with Mystromys and Otomys being the most abundant genera, accompanied by representatives of Muridae, Nesomyidae, Bathyergidae, and Gliridae. Other mammalian orders are represented by Macroscelididae (Macroscelidea), Soricidae (Eulipotyphla), Chiroptera, and Chrysochloridae (Afrosoricida). Taphonomic analyses reveal high fragmentation rates and pervasive manganese coatings, but a very low frequency and weak intensity of digestive etching on incisors. These patterns closely match modern barn owl (Tyto alba) assemblages, indicating accumulation primarily by a Category 1 nocturnal raptor. This accumulation mode appears consistent with other CoH micromammal assemblages, strengthening the reliability of inter-site faunal comparisons. Faunal composition indicates a landscape dominated by grassland and open savanna habitats, with localised wet or riverine environments suggested by the occurrence of Dasymys. Overall taxonomic similarities with other regional assemblages support a degree of ecological stability in the CoH during the Early Pleistocene. This assemblage provides a new data point for understanding micromammal palaeobiodiversity, site formation processes, and palaeoenvironmental dynamics in southern Africa.
Pachygazella is a small-sized bovid, originally unearthed from Shenmu County, Yulin City, northern China. Hitherto, the species has been placed in Caprini by most authors, and proposed to have a closer relationship with extant Naemorhedus and Capricornis. However, the lack of previous detailed morphological comparison and phylogenetic analysis hinders understanding of the taxonomic status and evolutionary relationship of the species with the other bovids. Here, we restudied the type specimen of the species with virtual 3D modelling, detailed comparison and phylogenetic analysis with other bovids. The result shows that it features a series of similar characters and is phylogenetically positioned as the sister group with the extant Naemorhedus and Capricornis, probably representing an ancestral lineage of these genera. The result supports the hypothesis proposed by the previous authors. Furthermore, we re-investigated the genus discovered from the other sites, resulting that they could not belong to Pachygazella, but should be reclassified as Gazella or Naemorhedus. Therefore, this species has been found only in the type locality so far. In addition, we discussed the evolution of Naemorhedus and Capricornis, proposing that the specimen from Zhoukoudian Loc.1 should be Capricornis and the taxonomic status of C. jianshiensis still requires further investigation.
Malocclusion and/or dental malformations were found in individuals of Mammuthus columbi (Falconer, 1857) from 15 Late Pleistocene localities in the Basin of Mexico. We hypothesise that malocclusions and/or malformations result from either nutritional deficiencies and a lack of essential minerals for dental development or genetic isolation and inbreeding. Our sample suggests that problems with the masticatory apparatus may be frequent in M. columbi, at least in Mexico, and thus should be studied on a broader geographical and chronological scale. Although our study cannot clarify the underlying causes, we suggest that future work should focus on the recovery of paleogenomic data as a primary research direction.
In this contribution we present and describe the first record of a fossil rheiform for the Late Pleistocene of the Torop & iacute;/Yupo & iacute; Formation (Marine Isotope Stage 3; ca. 65-50 ka.) in Corrientes Province, Argentina, which represents the second avian record for this unit. The specimen includes a distal fragment of a right tarsometatarsus preserving part of the diaphysis and an associated fragment of thoracic vertebra, recovered from fluvial deposits of the lowest levels of this study. The dimensions and morphology of the material allow it to be assigned to the flightless rheid Rhea sp. Considering the noticeable climatic oscillations recorded during the Marine Isotope Stage 3 (MIS 3), in which several Heinrich (colder) and Dansgaard-Oeschger (warmer) events existed, the presence of taxa related to temperate-cold environments recovered from the Lower Member (ca. 65 ka.) of the Torop & iacute;/Yupo & iacute; Formation (i.e. Chloephaga picta, Dolichotis patagonum) not recorded in the Upper Member suggests potential colder temperatures during the deposition of the Lower Member. This record increases the taxonomic diversity of fossil birds for the Pleistocene of Corrientes, which was previously limited to the anatid Chleophaga.
The Neuqu & eacute;n Basin in northwestern Patagonia, Argentina, holds the most important record of Cretaceous dinosaurs in South America. The Neuqu & eacute;n Group (Upper Cretaceous) is the richest dinosaur-bearing unit of the basin. It comprises the R & iacute;o Limay, the R & iacute;o Neuqu & eacute;n and the R & iacute;o Colorado subgroups. Malarguesaurus florenciae is a somphospondylian titanosauriform (Dinosauria, Sauropoda) from the R & iacute;o Neuqu & eacute;n subgroup (Portezuelo Formation), Neuqu & eacute;n Basin, Argentina. This specimen was found at Quebrada Norte site, Paso de las Bardas area, 190 km south of Malarg & uuml;e City, Mendoza Province. The aim of this study is to analyse the Malarguesaurus bone microstructure to elucidate the histological features and growth patterns. Histological thin sections made in skeletal elements reveal a presence of fibrolamellar bone tissue, suggesting an overall fast growth, however, the absence of growth marks advice for a sustained growth. The lack of growth marks can be interpreted as a product of the intense remodelling of the bone matrix. This contribution offers new insights into the bone microstructure and growth trajectory of Malarguesaurus titanosauriform from the Neuqu & eacute;n Basin during the Upper Cretaceous span.
