Pliocene

Body size is one of the most important determinants of the biology of a species, as it correlates with life history, energetic expenditure, diet, thermoregulation, and home range size, among other factors. Although the evolution of body size within the genus Homo is an important issue, the most influential large-scale studies have been performed over 20 years ago, with a recent interest in this issue only in the last few years. In the meantime, the widely accepted interpretation that there was a major shift in body size with the origin of Homo ergaster/erectus when compared Homo habilis, Homo rudolfensis, and australopithecines has come under criticism. Recent analyses have demonstrated that body size within early Homo is spatially and temporally variable, only showing significant increase in the Koobi Fora region after 1.7 Mya (Will & Stock, 2015). Broad temporal analyses of body size have highlighted the significant increase in body mass during the late Middle and Late Pleistocene (Ruff, 1997), and that brain size increases correspond closely with body mass increases throughout the Pleistocene (Grabowski, 2016). Even though new body size data is now accumulating rapidly for various parts of the hominin record (Arsuaga et al., 2015; Grabowski et al., 2015;  Will & Stock, 2015), no study comparable to the scope of Ruff et al. (1997) has since been performed.
In this paper we investigate taxonomic, spatial and temporal variation in two components of body size within the genus Homo: body mass and stature. We combine size estimates of hominin fossils from our own studies with other published data, resulting in the largest sample for a single study so far (n=319). The body size estimates cover roughly four million years (4.1 Mya – 11 ka) and derive from African, European and Asian specimens, including several genera and species of hominins. This data set allows for a detailed assessment of body size evolution within the genus Homo and relative to earlier hominins.
Analyses of the body size estimates demonstrate that: a) the origins of the genus Homo are characterized by a significant increase in body size compared to australopithecines and paranthropines, but also feature abundant spatial and temporal variation within an enlarged size range; b) members of Homo erectus/ergaster are marked by a diversification in body mass and stature rather than directional increase; c) a consistent and universal increase in body size is only established in Middle Pleistocene hominins (e.g. Sima de los Huesos, Atapuerca; Homo heidelbergensis), Neanderthals and modern humans after ca. 0.5 Mya; d) selection against smaller body mass and stature occurred in the late Early and Middle Pleistocene, and; e) there are no simple latitudinal trends in the variation of body size estimates within Middle and Late Pleistocene Homo in Europe. These results have implications for studies concerned with human dispersal and encephalization, and more generally for how we interpret the evolution and biology of our genus. In light of the above, rather than focusing exclusively on species means and unidirectional models, perspectives that emphasize spatio-temporal variability and phenotypic plasticity might be more fruitful frameworks for interpreting the evolution of body size in our genus.

In the austral summer of 2006/7 the ANDRILL MIS (ANtarctic geological DRILLing-McMurdo Ice Shelf) project
recovered a 1285 m sediment core from beneath the Ross Ice Shelf near Ross Island, Antarctica in a flexural
moat associated with volcanic loading. The upper ~600 m of this core contain sediments recording 38 glacial/
interglacial cycles of Early Pliocene to Pleistocene time, including 13 discrete diatomite units (DUs). The
longest of these, DU XI, is ~76 m-thick, and has been assigned an Early to Mid-Pliocene age (5–3 Ma). A
detailed record of the siliceous microfossil assemblages in DU XI is used in conjunction with geochemical and
sedimentological data to subdivide DU XI into four discrete subunits of continuous sedimentation. Within
each subunit, changes in diatom assemblages have been correlated with the δ18O record, providing a temporal
resolution up to 600 yr, and allowing for the construction of a detailed age model and calculation of associated
sediment accumulation rates within DU XI. Results indicate a productivity-dominated sedimentary record
with greater proportions of hemipelagic mud accumulating during relatively cool periods. This implies that
even during periods of substantial warmth, Milankovitch-paced changes in Antarctic ice volume can be linked
to ecological changes recorded in diatom assemblages.

We investigate the distributions of representatives of the family Melanopsidae (Gastropoda: Caenogastropoda: Cerithioidea) from the late Cretaceous to present-day. The present contribution discusses and partly revises former schemes of melanopsid dispersal during the Cenozoic, all of which were based on outdated stratigraphic and tectonic concepts as well as an incompletely considered fossil record. Conflating a comprehensive and stratigraphically well-constrained fossil record, modern paleogeographical reconstructions and contemporary climate data, our goal is to present a thorough model of melanopsid distribution and its changes over the Cenozoic as well as its paleogeographical and climatic constraints. The family Melanopsidae evolved about 90 Ma ago in the late Turonian from brackish cerithioidean ancestors. Cretaceous and Paleogene species occur in marginal marine to brackish environments along the shores of the Tethys and Paratethys seas. The extant clades of Melanopsis likely derive from the evolution of freshwater Melanopsis on the Balkan Peninsula back in the late early Miocene. Up to the Pliocene, freshwater species spread toward southwestern and southeastern Europe and successively replaced brackish-water representatives, paralleling a general decline of latter systems during the late Cenozoic. The southwards expansion of Melanopsis and its simultaneous retreat from northern latitudes resulted in the disjunct distribution pattern observed today.

The genus Holandriana first appeared in northern Italy in the late early Miocene. The genera Microcolpia and Esperiana both first occurred in the late Miocene and likely derive from brackish-water Melanopsis species native to peri-Paratethyan lakes. The present-day biogeographic isolation of the three latter genera and Melanopsis roots in the climatic deterioration and the disappearance of major lake systems in southeastern Europe. While thermophilous Melanopsis retreated to the warm, dry climates of the Mediterranean and Middle East, Holandriana, Microcolpia and Esperiana adapted to the seasonal, cold-temperate climate of southeastern and eastern Europe and some species became restricted to thermal springs.

Numerosos restos de gastrópodos fósiles han sido encontrados en niveles edafizados de la sección media de la Formación Aisol (Mendoza, Argentina). Esta sección estratigráfica es portadora de una asociación de mamíferos fósiles que sugiere una edad Plioceno temprano (posiblemente SALMA Montehermosense). Se han podido identificar al menos cuatro taxones: Succinea Draparnau (Succineidae), Gastrocopta Wollaston (Vertiginidae), Bostryx Troschel (Bostrycidae) y una especie nueva del género Radiodiscus Pilsbry y Ferriss (Charopidae). Los registros fósiles de moluscos pulmonados terrestres en Argentina son escasos y se restringen al Cuaternario. El hallazgo de estos taxones en la sección media de la Formación Aisol (Plioceno temprano) reviste gran importancia ya que constituye el registro más antiguo de los géneros Gastrocopta y Succinea para la Argentina, el primer registro del género Bostryx para la Provincia de Mendoza, y el primer registro de la familia Charopidae (Radiodiscus sanrafaelensis nov. sp.) en depósitos de edad Pliocena en Argentina.

New occurrences of Sinusichnus sinuosus described in the Cenozoic of Spain evidence the almost continuous fossil record of this ichnospecies from the Upper Cretaceous to the Lower Pliocene. Morphological and size features of these highly regular sinusoidal burrows have been analyzed, showing a very recurrent constructional pattern through time. Such features are also constant along the ontogeny of the producer. The large number of similarities that this ichnogenus shares with fodinichnial burrow systems, such as Thalassinoides, Ophiomorpha, or Spongeliomorpha, point to a crustacean authorship. Since this sinusoidal architecture is also common among some graphoglyptids, other behavioral strategies are discussed. The ichnogenus Sinusichnus occurs commonly in shallow marine environments, in particular to deltaic depositional settings.

Human evolutionary scholars have long supposed that the earliest stone tools were made by the genus Homo and that this technological development was directly linked to climate change and the spread of savannah grasslands. New fieldwork in West Turkana, Kenya, has identified evidence of much earlier hominin technological behaviour. We report the discovery of Lomekwi 3, a 3.3-million-year-old archaeological site where in situ stone artefacts occur in spatiotemporal association with Pliocene hominin fossils in a wooded palaeoenvironment. The Lomekwi 3 knappers, with a developing understanding of stone’s fracture properties, combined core reduction with battering activities. Given the implications of the Lomekwi 3 assemblage for models aiming to converge environmental change, hominin evolution and technological origins, we propose for it the name ‘Lomekwian’, which predates the Oldowan by 700,000 years and marks a new beginning to the known archaeological record.

In 1979, several specimens of Rhinocerotidae were collected from the Late Miocene deposits of the Zala Subbasin, Pannonian Basin, Western Hungary and were inventoried as Rhinoceros sp. Based on morphological and metric grounds, this material is here referred to " Dihoplus " megarhinus (de Christol), a species previously known only from Pliocene localities. This is the earliest record of the species in Europe. Our results support the hypothesis that the origin of " D ". megarhinus took place in Asia and that this species successively dispersed towards Western Europe during the end of the Miocene. Systématique Morphologie Biochronologie Paléobiogéographie r é s u m é En 1979, plusieurs spécimens de Rhinocerotidae ont été collectés dans les dépôts du Miocène supérieur du bassin de Zala, en Pannonie (Hongrie occidentale), et alors attribués à Rhinoceros sp. Sur la base des données métriques et morphologiques, ce matériel est ici attribué à « Dihoplus » megarhinus (de Christol), une espèce précédemment connue seulement dans des localités du Pliocène. Cette nouvelle découverte est la plus ancienne mention en Europe pour « D ». megarhinus. Notre analyse suggère que l'origine de « D ». megarhinus a eu lieu en Asie et que cette espèce s'est probablement dispersée en Europe occidentale dès le Miocène supérieur.