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A palynological record from Girraween Lagoon sediments (Darwin region of the Northern Territory, Australia) provides detailed long-term insight into tropical savanna vegetation community patterns, climatic and fire relationships, through Marine Isotope Stage 4 (MIS 4: 71–57 thousand years ago, ka) and Marine Isotope Stage 3 (MIS 3: 57–29 ka). Owing to a lack of data in reconstructing northern Australian environments, this paper looks to define and describe to a greater degree the nature and scope of these stadial and interstadial stages for the region. Girraween Lagoon simultaneously provides proximal palaeoecological data for the time and region of Aboriginal people's first arrival into Australia, also encompassing the late Pleistocene continental decline of megafauna. This study provides a dataset enabling full exploration of long-term people-landscape and faunal-floral interactions. Sea levels and associated variations imposed on the transportation of moisture and heat, held implications for MIS 4 and MIS 3 monsoon strength, which was particularly consequential for Girraween regional ecology. Results reveal a prolonged transition from wooded- to grassy-savanna, into a cool drier semi-arid savanna. Increasingly episodic delivery of moisture influenced the permanency of freshwater in the landscape. • A detailed picture of vegetation in monsoonal north Australia during MIS 4 and MIS 3. • An ultimate transition from grassy eucalypt savanna into semi-arid savanna revealed. • Changed monsoonal delivery particularly consequential for regional ecology. • An indication of baseline landscapes during people's first arrival into Australia. • Assisting to place megafaunal decline within an ecological landscape. [ABSTRACT FROM AUTHOR]

A rich insect fauna is found in the Cretaceous (Aptian) Nova Olinda Member of the Crato Formation in the Araripe Basin, northeastern Brazil. The Crato Formation was deposited close to the centre of the supercontinent Gondwana, prior to significant rifting. In this paper, we analyzed remains of 1135 insect specimens, representing 55 families, within two limestone facies of the Nova Olinda Member: pale yellow and dark gray limestones. We collected taphonomical data and assessed the paleoecological significance of insect faunas in terms of their distribution and interaction with the paleoenvironment. The insect fauna is dominanted by fully terrestrial taxa despite preservation in an aquatic paleoenvironment. Considering both facies, the distribution of insect families is similar throughout the Nova Olinda Member, which excludes possible overlapping of one entomofauna over another. The pale yellow limestones near the top of the section are richer in fossil insect content and show a higher incidence of aquatic and semiaquatic insects preserved in dorsoventral view compared to the dark gray limestones. This suggests that the Crato insects preserved in the pale yellow limestones experienced short transport distances or prolonged decay or both. In contrast, insects preserved in the dark gray limestones appear proportionally with higher degrees of disarticulation than those preserved in the pale yellow limestones, indicating that these insects underwent a higher degree of postmortem transport in the biostratinomic stage. Compared to descriptions of other Early Cretaceous assemblages, the taxonomic literature of Crato Paleoentomofauna shows distinct differences. The Yixian and Zaza formations are described as being dominated by beetles and wasps. The Crato Formation, however, is relatively richer in Paleoptera species. Both the sedimentary facies studied and the paleoentomological content reveal a complex ecosystem inserted in a depositional setting, similar to modern long-standing wetlands, and where periodically flooded zones were surrounded by dry lands with xeromorphic vegetation. • Crato insects preserved in the dark gray limestones appear proportionally with higher degrees of disarticulation. • The paleoentomological content reveals an ecosystem inserted in a setting similar to modern long-standing wetlands. • Compared to other Early Cretaceous assemblages, the Crato Paleoentomofauna is relatively richer in Paleoptera species. [ABSTRACT FROM AUTHOR]

In the comment on our paper, Prevosti et al. (2024) make a series of criticisms regarding the alleged lack of information provided on the dated samples and their geographic and stratigraphic provenance. In this contribution, we will give a reply to their comments. Our new zircon dating achieves the objective of the original study and provides valuable insights into the paleoecological dynamics of the period. It was out of the scope for our work to undertake a high resolution stratigraphical/sedimentological and dating analysis of each of the selected outcrops/sites. • First zircon dates from Neogene classic sites in central Argentina are provided. • The new dating achieves the objective of the original study. • Dating sets a solid time frame for paleoecological interpretations. [ABSTRACT FROM AUTHOR]

Sanz-Pérez et al. (2024) recently, based on detrital zircon, presented new maximum depositional ages for several sites of the Neogene of central Argentina to constraint the age of the faunas studied with stable isotopes. Unfortunately, the precise provenance of the dated samples is not clear. In this comment, we discuss the absence of key basic information to replicate their (geochronological) study, or even to evaluate their inferences and conclusions. Without more information about the precise geographic provenance of the dated detrital zircons, and their stratigraphic position in the geological profile/schema of each locality the interpretation of the authors is not supported by the presented information. • Detrital Zircon Dates presented by Sanz-Pérez et al. (2024) lack of precise geographic location information. • These samples lack of any stratigraphic position in the profile of each location. • Based on a new work, the date of Salinas Grandes is from the top of the profile, and irrelevant for age constraint. • Geochronological inferences of Sanz-Pérez et al. (2024) are unsupported by the data presented in the paper. [ABSTRACT FROM AUTHOR]

The Late Pliocene fossil locality of Las Higueruelas (central Spain) has been known for many decades; however, in this paper, we describe the fauna of small-sized vertebrates (fish, amphibians, squamate reptiles, and rodents) for the first time based on pre-existing collections in the Museo Provincial de Ciudad Real. In addition to updating the taxonomical nomenclature of previously-published faunal lists, we also report the new occurrences of four fish taxa, a lizard (Lacertidae indet.), and several snakes (Malpolon gr. monspessulanus-mlynarskii , cf. Zamenis scalaris , and a large-sized indetermined viperid, probably from the Oriental vipers group or genus Daboia). The only rodent is identified as Stephanomys minor. Overall this assemblage indicates the predominance of open, dry environments and shrubby vegetation close to more grassy and riparian woodland under warm (15.1 ± 1.8 °C) and semi-arid (556 ± 40 mm) conditions. There was 4-month period of summer aridity similar to a modern Mediterranean climate. Most of the aquatic taxa (Pleurodeles , Pelophylax , and Natrix) were able to tolerate brackish environments, and the amphibians suggest the presence of deep and stable water bodies, with a long hydroperiod and aquatic vegetation, necessary for reproduction. Las Higueruelas is confirmed as being assigned to subchron 2An.1r (3.116–3.032 Ma) like the Camp dels Ninots Konservat-Lagerstätten (Girona, Spain). Palaeoclimate reconstruction for both localities is consistent with the later stages of the mid-Piacenzian Warm Period. Palaeontological comparison between the two sites may support either a small difference in age, or most probably, varied climate zonations within the Iberian Peninsula, with a north-eastern area allowing a local survival of Early Pliocene taxa that are absent from Las Higueruelas. [Display omitted] • The small vertebrates from Las Higueruelas (Spain) are described for the first time. • Fish, herpetofauna, and rodent represent up to 18 different taxa. • Stephanomys minor and palaeomagnetism constrain to the cron 2An.1r (3.03–3.11 Ma). • Predominance of open environments under temperate and dry climate conditions. • Central Spain does not seem to allow local survival of early Pliocene taxa. [ABSTRACT FROM AUTHOR]