A unified conceptual model of coastal response to accelerating sea level rise, Florida, U.S.A.

Aggregation of paleo-environmental data derived from geological investigations conducted on the shoreface and inner shelf of Florida's six coastal geomorphic sectors revealed a common and synchronous response to a decelerating rate of Holocene sea level rise: (1) early Holocene overstep and submergence (∼10-5 mm yr-1), (2) mid-Holocene erosional shoreface retreat (∼2 mm yr-1), and (3) late Holocene stabilization (<1 mm yr-1). Linear best-fit analysis of sea level data collected at 14 NOAA tide gauge stations distributed along the entire Florida coast indicates the rate of sea level rise has accelerated from a historical average of 3.1 mm yr-1 (<1972-2022; range 2.2 to 4.2) to 5.9 mm yr-1 (1993-2022; range 4.8 to 6.9) and 8.2 mm yr-1 during the 21st century (2003-2022; range 7.6 to 10.0). The 21st century rates vary between stations, however all fall within the range of values documented during the early Holocene; a time when Florida's coastline was rapidly transgressed. Recent studies have demonstrated that the destabilizing effects of this acceleration on Florida's coastal geomorphology and ecology are already evident. Rates of rise are expected to continue increasing and this will accelerate the pace and scale of landward translation and submergence of Florida's coastal environment.

Rare earth elements as statistical sentinels of pollution and paleoenvironments?: Application to a highly polluted estuary in southwestern Spain.

Multivariate analyses have been applied to the REE contents of three cores collected in the Tinto estuary, SW Spain, an extremely polluted area. Results indicate an extremely correlation between all REE, which behave as a single variable. A slight natural pollution peak and three anthropogenic pollution peaks are identified, related with the first mining activities, the Roman period and a recent intensive mining accompanied by a heavy industrial pollution. In all these peaks, the increase of Cu is parallel to that of MREE, which are configured as the best indicators of pollution among REE. Statistical analyses clearly differentiate four groups, each consisting of samples from different environments. Although grain size and this strong pollution alter the study of REE as environmental indicators, it is possible to recognise groups of samples with a common origin or to identify the surface extent of a given pollution peak.

Saccharides in atmospheric particulate and sedimentary organic matter: Status overview and future perspectives.

Saccharides are omnipresent compounds in terrestrial and marine ecosystems. Since the 2000s, their role in environmental and geochemical studies has significantly increased, but only anhydrosaccharides (mainly levoglucosan) have been reviewed. Here we present the wider knowledge about saccharides in organic matter of aerosols, bottom sediments, soils, dust, and sedimentary rocks. The main purpose here is to characterize the possible sources of saccharides, as well as sacharol formation, seasonal variability, and the possible applications in environmental and paleoenvironmental interpretations. Different saccharide sources were designated, including biomass burning, and particulate matter such as pollen, spores, lichen, and fungi, as well as polysaccharide decomposition as possible inputs of monosaccharides. The main focus was on the most common saccharides encountered in environmental samples and sedimentary rocks. These are the mono- and disaccharides glucose, fructose, sucrose, and trehalose, and sacharols arabitol and mannitol. The anhydrosaccharides levoglucosan, mannosan, and galactosan were evaluated as ancient wildfire indicators and industrialization tracers found in lacustrine sediments starting from Pleistocene to contemporary deposits. However, other anhydrosaccharides like xylosan and arabinosan were also found as products of fossil wood burning. These anhydrosaccharides have the potential to be further tracers of hemicellulose burning. Additional recommendations are proposed for future research, including environmental and paleoenvironmental topics that need to be addressed.

Plant wax biomarkers in human evolutionary studies.

Plant wax biomarkers are an innovative proxy for reconstructing vegetation composition and structure, rainfall intensity, temperature, and other climatic and environmental dynamics. Traditionally used in earth sciences and climate studies from "off-site" ocean and lake records, biomarker research is now incorporated in archeology and paleoanthropology to answer questions relating to past human-environment interactions and human evolution. Biomarker research is generating new and exciting information on the ecological context in which Homo and its closest relatives evolved, adapted, and invented stone tool technologies. In this review, we examine plant wax biomarkers and their use in reconstructing past plant landscapes and hydroclimates. We summarize the applications of plant wax molecular proxies in archeological research, assess challenges relating to taphonomy, consider the role of modern plant ecosystems in interpreting ancient habitats, and examine case studies conducted at key paleoanthropological locations in eastern and southern Africa and Europe.

Isotopic Indications of Late Pleistocene and Holocene Paleoenvironmental Changes at Boodie Cave Archaeological Site, Barrow Island, Western Australia.

This paper presents the first application of mammal tooth enamel carbonate stable isotope analysis for the purpose of investigating late Pleistocene-early Holocene environmental change in an Australian archaeological context. Stable carbon (δ13C) and oxygen (δ18O) isotope ratios were analyzed from archaeological and modern spectacled hare wallaby (Lagorchestes conspicillatus) and hill kangaroo (Osphranter robustus) tooth enamel carbonates from Boodie Cave on Barrow Island in Western Australia. δ18O results track the dynamic paleoecological history at Boodie Cave including a clear shift towards increasing aridity preceding the onset of the Last Glacial Maximum and a period of increased humidity in the early to mid-Holocene. Enamel δ13C reflects divergent species feeding ecology and may imply a long-term shift toward increasing diversity in vegetation structure. This study contributes new data to the carbonate-isotope record for Australian fauna and demonstrates the significant potential of stable isotope based ecological investigations for tracking paleoenvironment change to inter-strata resolution.

Diversity and paleoenvironmental implications of an elasmobranch assemblage from the Oligocene-Miocene boundary of Ecuador.

The occurrence and diversity of elasmobranchs from the Oligocene-Miocene boundary from Tropical America is poorly known in comparison with the paleodiversity from younger Neogene intervals of the region. Here we describe a new elasmobranch assemblage from the rich fossil site of Montañita-Olón (Dos Bocas Formation, Santa Elena, Ecuador), where other vertebrates have already been described: for example, sea turtles and cetaceans. We report a total of 27 elasmobranch taxa, 19 of which are new fossil records for Ecuador, 10 new records for the Central Eastern Pacific and four new records for South America. Additionally, in order to reconstruct the environment where these marine remains were deposited, we performed abundance, paleobathymetric and habitat preference analyses, concluding that they were likely deposited in an outer neritic (open shelf) environment. The study of Oligocene and early Miocene marine elasmobranchs faunas in Tropical America is key to addressing the issues in the evolutionary history of this group.

The ecology of Australopithecus anamensis in the early Pliocene of Kanapoi, Kenya.

Australopithecus anamensis is a pivotal species in human evolution. It is likely to be the direct ancestor of Australopithecus afarensis and the species that may have given rise to the Homo and Paranthropus lineages. It had a suite of adaptations for habitual bipedalism and a diet that differed from that of earlier hominin species. Under what environmental and ecological conditions did this suite of adaptations arise? The early Pliocene site of Kanapoi in the Lake Turkana Basin of Kenya has the largest sample of A. anamensis in eastern Africa and a rich record of fossil vertebrates. Most Kanapoi fossils are chronologically well constrained by radiometrically dated tephras between the ages of 4.2 and 4.1 million years ago. Sedimentological, isotopic, and faunal data indicate that the environments of Kanapoi during the early Pliocene had a complex range of vegetation types that included closed woodlands, shrubs, and grasslands near a river (for most of the sequence) or lake. These were dynamic landscapes that could shift rapidly from fluvial to lacustrine conditions, and then back. Australopithecus anamensis shared its environments with at least 10 species of very large herbivores, which undoubtedly played a major role in modifying the landscape by opening wooded areas and providing pathways for bipedal hominins. Hominins may have competed for terrestrial resources with abundant suids (Nyanzachoerus and Notochoerus) and for arboreal resources with monkeys (Parapapio being the most common cercopithecid). Kanapoi had a formidable group of predators that included a very abundant species of hyena (Parahyaena howelli), two sabre-tooth felids (Dinofelis and Homotherium), a giant otter (Enhydriodon cf. dikikae), and three species of crocodiles. Various measures of abundance indicate that A. anamensis was an important component of the Kanapoi early Pliocene ecosystems, and that its key adaptations allowed this species to thrive in complex and dynamic landscapes.

Kanapoi revisited: Paleoecological and biogeographical inferences from the fossil fish.

Fish fossils were recovered from three different depositional contexts at the Pliocene Kanapoi site to: 1) test the assumption that habitat and ecology of modern fish taxa can predict habitat and ecology of fossil taxa; 2) reconstruct the lake and river environments in the Kanapoi Formation, with reference to fish fossils from the nearby Lothagam site deposits; and 3) investigate biogeographical inferences from the fossils. We compare the Kanapoi fish taxa and their depositional environments with the taxa and environments in modern Lake Turkana, and with another Plio-Pleistocene fauna from the eastern Turkana Basin. Taphonomic caveats are discussed. Our results support the use of ecological preferences of modern fish to predict past preferences. Our analysis of the Kanapoi fossils also indicates that the Pliocene Lonyumun Lake had a diverse fauna, with an unusual mix of taxa compared to the modern lake. The presence of possibly endemic species in the Pliocene lake may additionally represent a period of isolation during this epoch. Few fish fossils were recovered in the deposits of the ancestral Kerio River, a primary affluent of Lonyumun Lake then as now, but those present indicate a different ecology than that interpreted for the modern lake. Previously unknown fish taxa which enter the lake during the Pliocene suggest the existence of a connection between the Nile River and the Turkana Basin, which may have been viable for other vertebrates, including hominins.

Organic-mineral interfacial chemistry drives heterogeneous nucleation of Sr-rich (Ba x , Sr1-x )SO4 from undersaturated solution.

Sr-bearing marine barite [(Ba x , Sr1-x )SO4] cycling has been widely used to reconstruct geochemical evolutions of paleoenvironments. However, an understanding of barite precipitation in the ocean, which is globally undersaturated with respect to barite, is missing. Moreover, the reason for the occurrence of higher Sr content in marine barites than expected for classical crystal growth processes remains unknown. Field data analyses suggested that organic molecules may regulate the formation and composition of marine barites; however, the specific organic-mineral interactions are unclear. Using in situ grazing incidence small-angle X-ray scattering (GISAXS), size and total volume evolutions of barite precipitates on organic films were characterized. The results show that barite forms on organic films from undersaturated solutions. Moreover, from a single supersaturated solution with respect to barite, Sr-rich barite nanoparticles formed on organics, while micrometer-size Sr-poor barites formed in bulk solutions. Ion adsorption experiments showed that organic films can enrich cation concentrations in the adjacent solution, thus increasing the local supersaturation and promoting barite nucleation on organic films, even when the bulk solution was undersaturated. The Sr enrichment in barites formed on organic films was found to be controlled by solid-solution nucleation rates; instead, the Sr-poor barite formation in bulk solution was found to be controlled by solid-solution growth rates. This study provides a mechanistic explanation for Sr-rich marine barite formation and offers insights for understanding and controlling the compositions of solid solutions by separately tuning their nucleation and growth rates via the unique chemistry of solution-organic interfaces.

Flight over the Proto-Caribbean seaway: Phylogeny and macroevolution of Neotropical Anaeini leafwing butterflies.

Our understanding of the origin and evolution of the astonishing Neotropical biodiversity remains somewhat limited. In particular, decoupling the respective impacts of biotic and abiotic factors on the macroevolution of clades is paramount to understand biodiversity assemblage in this region. We present the first comprehensive molecular phylogeny for the Neotropical Anaeini leafwing butterflies (Nymphalidae, Charaxinae) and, applying likelihood-based methods, we test the impact of major abiotic (Andean orogeny, Central American highland orogeny, Proto-Caribbean seaway closure, Quaternary glaciations) and biotic (host plant association) factors on their macroevolution. We infer a robust phylogenetic hypothesis for the tribe despite moderate support in some derived clades. Our phylogenetic inference recovers the genus Polygrapha Staudinger, [1887] as polyphyletic, rendering the genera FountaineaRydon, 1971 and Memphis Hübner, [1819] paraphyletic. Consequently, we transfer Polygrapha tyrianthina (Salvin & Godman, 1868) comb. nov. to Fountainea and Polygrapha xenocrates (Westwood, 1850) comb. nov. to Memphis. We infer an origin of the group in the late Eocene ca. 40 million years ago in Central American lowlands which at the time were separated from South America by the Proto-Caribbean seaway. The biogeographical history of the group is very dynamic, with several oversea colonization events from Central America into the Chocó and Andean regions during intense stages of Andean orogeny. These events coincide with the emergence of an archipelagic setting between Central America and northern South America in the mid-Miocene that likely facilitated dispersal across the now-vanished Proto-Caribbean seaway. The Amazonian region also played a central role in the diversification of the Anaeini, acting both as a museum and a cradle of diversity. We recover a diversification rate shift in the Miocene within the species-rich genus Memphis. State speciation and extinction models recover a significant relationship between this rate shift and host plant association, indicating a positive role on speciation rates of a switch between Malpighiales and new plant orders. We find less support for a role of abiotic factors including the progressive Andean orogeny, Proto-Caribbean seaway closure and Quaternary glaciations. Miocene host plant shifts possibly acted in concert with abiotic and/or biotic factors to shape the diversification of Anaeini butterflies.

A Tournaisian (earliest Carboniferous) conglomerate-preserved non-marine faunal assemblage and its environmental and sedimentological context.

A conglomerate bed from the Tournaisian Ballagan Formation of Scotland preserves a rich array of vertebrate and other nonmarine fossils providing an insight into the wider ecosystem and paleoenvironment that existed during this pivotal stage of Earth history. It challenges hypotheses of a long-lasting post-extinction trough following the end-Devonian extinction event. The fauna recovered includes a wide size range of tetrapods, rhizodonts, and dipnoans, from tiny juveniles or small-bodied taxa up to large adults, and more than one taxon of each group is likely. Some fauna, such as actinopterygians and chondrichthyans, are rare as macrofauna but are better represented in the microfossil assemblage. The fauna provides evidence of the largest Carboniferous lungfish ever found. The specimens are preserved in a localized, poorly-sorted conglomerate which was deposited in the deepest part of a river channel, the youngest of a group of channels. In addition to the fossils (micro- and macro-), the conglomerate includes locally-derived clasts of paleosols and other distinctive elements of the surrounding floodplains. Charcoal fragments represent small woody axes and possible larger trunk tissue from arborescent pteridosperms. Preservation of the fossils indicates some aerial exposure prior to transport, with abrasion from rolling. The findings presented here contrast with other published trends in vertebrate size that are used to interpret a reduction in maximum sizes during the Tournaisian. The richness of the fauna runs counter to the assumption of a depauperate nonmarine fauna following the end-Devonian Hangenberg event, and charcoal content highlights the occurrence of fire, with the requisite levels of atmospheric oxygen during that stage.

Paleoenvironmental Evolution of Continental Carbonates in West-Central Brazil

ABSTRACT This paper presents a sedimentological and stratigraphical study of Quaternary (Middle to Late Pleistocene/Holocene) continental carbonates outcrops inside Pantanal Basin and its surroundings, especially in Serra da Bodoquena, Pantanal do Miranda and Corumbá/Ladário plateau, in the state of Mato Grosso do Sul, as well as in Serra das Araras, in the state of Mato Grosso. The aim is to understand the depositional paleoenvironments and analyse climate and tectonic influences in their genesis and evolution. The results show that the deposition of these continental carbonates started in the Middle to Late Pleistocene and have continued, with some interruptions, until the present days. Sedimentary successions were identified in the different areas, without complete correlation. Two sedimentary successions separated by an erosional surface were described in Serra da Bodoquena and Serra das Araras. In Corumbá and Pantanal do Miranda, only one succession was described. These successions were deposited in elongated lakes parallel to fault planes; small lakes, related plains and plateaus; springs related to cliffs produced by faulting; rivers conditioned by topographic variation. The climatic interpretation, without proper temporal resolution, obtained by the stable-isotope composition and stratigraphic interpretation, indicates alternation of dry and wet periods. The Neoproterozoic faults with their neotectonics and the subsidence of the Pantanal Basin, are the major control for carbonated water flow and development of depositional areas, gradually turning plateaus into slight tilted areas, allowing the evolution of depositional systems from lakes to rivers.

The paleoenvironments of azhdarchid pterosaurs localities in the Late Cretaceous of Kazakhstan.

Five pterosaur localities are currently known from the Late Cretaceous in the northeastern Aral Sea region of Kazakhstan. Of these, one is Turonian-Coniacian in age, the Zhirkindek Formation (Tyulkili), and four are Santonian in age, all from the early Campanian Bostobe Formation (Baibishe, Akkurgan, Buroinak, and Shakh Shakh). All so far collected and identifiable Late Cretaceous pterosaur bones from Kazakhstan likely belong to Azhdarchidae: Azhdarcho sp. (Tyulkili); Aralazhdarchobostobensis (Shakh Shakh); and Samrukianessovi (Akkurgan). These latter two taxa, both from the Bostobe Formation might be synonyms. Azhdarcho sp. from the Zhirkindek Formation lived in a tropical-to-subtropical relatively humid climate on the shore of an estuarine basin connected to the Turgai Sea. Known fossils were collected in association with brackish-water bivalves and so the overall paleoenvironment of this pterosaur was likely an estuarine marsh as indicated by the dominance of conifers and low relative counts of ferns and angiosperms. Aralazhdarchobostobensis, from the Bostobe Formation, lived on a coastal fluvial plain along the Turgai Sea. This paleoenvironment was either floodplain (Akkurgan, Buroinak, and Shakh Shakh) or estuarine (Baibishe). In the Santonian - early Campanian, shallow waters near this coastal plain were sites for the intensive accumulation of phosphates under upwelling conditions caused by strong winds from the ancient Asian landmass. These winds also caused significant aridization of the climate during this time. We speculate that pterosaurs may have been attracted to this area by the abundant resources in the bio-productive estuaries and nearshore upwelling waters.

Review of taxonomy, geographic distribution, and paleoenvironments of Azhdarchidae (Pterosauria).

The taxonomy, geographic distribution, and paleoenvironmental context of azhdarchid pterosaurs are reviewed. All purported pteranodontid, tapejarid, and azhdarchid specimens from the Cenomanian Kem Kem beds of Morocco are referred to a single azhdarchid taxon, Alanqa saharica. The four proposed autapomorphies of Eurazhdarcho langendorfensis from the lower Maastrichtian Sebes Formation of Romania are based on misinterpretations of material and this taxon is likely a subjective junior synonym of Hatzegopteryx thambema. Among 54 currently reported azhdarchid occurrences (51 skeletal remains and 3 tracks) 13% are from lacustrine deposits, 17% from fluvial plain deposits, 17% from coastal plain deposits, 18% from estuarine and lagoonal deposits, and 35% from costal marine deposits. Azhdarchids likely inhabited a variety of environments, but were abundant near large lakes and rivers and most common in nearshore marine paleoenvironments.

Phylogenetic comparative methods complement discriminant function analysis in ecomorphology.

In ecomorphology, Discriminant Function Analysis (DFA) has been used as evidence for the presence of functional links between morphometric variables and ecological categories. Here we conduct simulations of characters containing phylogenetic signal to explore the performance of DFA under a variety of conditions. Characters were simulated using a phylogeny of extant antelope species from known habitats. Characters were modeled with no biomechanical relationship to the habitat category; the only sources of variation were body mass, phylogenetic signal, or random "noise." DFA on the discriminability of habitat categories was performed using subsets of the simulated characters, and Phylogenetic Generalized Least Squares (PGLS) was performed for each character. Analyses were repeated with randomized habitat assignments. When simulated characters lacked phylogenetic signal and/or habitat assignments were random, <5.6% of DFAs and <8.26% of PGLS analyses were significant. When characters contained phylogenetic signal and actual habitats were used, 33.27 to 45.07% of DFAs and <13.09% of PGLS analyses were significant. False Discovery Rate (FDR) corrections for multiple PGLS analyses reduced the rate of significance to <4.64%. In all cases using actual habitats and characters with phylogenetic signal, correct classification rates of DFAs exceeded random chance. In simulations involving phylogenetic signal in both predictor variables and predicted categories, PGLS with FDR was rarely significant, while DFA often was. In short, DFA offered no indication that differences between categories might be explained by phylogenetic signal, while PGLS did. As such, PGLS provides a valuable tool for testing the functional hypotheses at the heart of ecomorphology.