• Mißbach et al. (2021) report the existence of indigenous organic molecules and gases in primary fluid inclusions in c. 3.5-billion-year-old
barites from the
Dresser Formation (
Pilbara Craton,
Australia), providing evidence of the organic composition of primordial fluids that were available for the early microbes. • A study on the 3.4-billion-year old organic films from the
Buck Reef Chert (
Kaapvaal craton,
South Africa) is published by Alleon et al. (2021), who interpret their findings as indicating that early
Archean organic films carry chemical information directly related to their original molecular compositions, and evaluate the implications of their finding for the knowledge of the initial chemical nature of organic microfossils found in ancient rocks. • A study on the evolution of marine
dissolved organic carbon concentrations is published by Fakhraee et al. (2021), who interpret their findings as indicating that the overall size of the marine dissolved organic carbon reservoir has likely undergone very little variation through Earth's history, casting doubt on previously hypothesized links between marine dissolved organic carbon levels and the emergence and radiation of early animals. • A study on the age of the Ediacaran
stratigraphic successions in South China, and on its implications for the knowledge of the timing of the rise and early evolution of complex macroscopic life, is published by Yang et al. (2021). • A study on the carbon isotopic composition of marine carbonates and on the age of the Ediacaran Nama Group (
Namibia) and other geological formations from the Ediacaran-Cambrian transition around the world, and on their implications for the knowledge of the early radiation of animals, is published by Bowyer et al. (2021). • A study on the timing and sequence of events through the early
Darriwilian leading to the Great Ordovician Biodiversification Event is published by Rasmussen, Thibault & Rasmussen (2021), who interpret their findings as refuting the proposed link between the
Ordovician meteor event and the icehouse conditions preceding the Ordovician radiation, and indicating that the meteorite fallout postdated both the onset of glaciation and the onset of the Ordovician radiation. • A study on the impact of volcanism-related delivery of the nutrient phosphorus to the Late Ordovician ocean on global cooling and
Late Ordovician mass extinction is published by Longman et al. (2021). • A study evaluating the validity of the Devonian bioregionalization first proposed by
Boucot, Johnson & Talent (1969) is published by Dowding, Ebach & Madroviev (2021). • Evidence of prolonged and repeated oxygen stress in the Appalachian Basin associated with the
Late Devonian extinctions is presented by Boyer et al. (2021). • Rakociński et al. (2021) report very large anomalous
mercury spikes from the south-western part of Tian Shan (
Uzbekistan), and interpret this finding as evidence of intensive volcanic activity both predating and occurring during the
Hangenberg Crisis. • Evidence from the
South China Block indicative of extensive
felsic volcanic activity coincident with the Permian–Triassic extinction event is presented by Zhang et al. (2021), who interpret their findings as indicating that felsic volcanism in South China was a key contributor to the environmental deterioration that led to the Permian–Triassic extinction event. • Evidence from the southern Karoo Basin of South Africa indicative of at least four atmospheric carbon dioxide spikes coinciding with extinctions on land and at sea from the Late Permian to the Middle Triassic is presented by
Retallack (2021). • Lu et al. (2021) present a record of volcanism and environmental changes from
Carnian lake succession of the Jiyuan Basin (North China), and interpret their findings as indicative of four pulses of volcanism which were probably responsible for the global carbon isotope excursions that marked the
Carnian pluvial episode and drove major environmental changes in the Jiyuan Basin. • A study evaluating whether fuel-driven changes to fire activity during the Cretaceous period had the ability to counteract rising atmospheric oxygen at this time is published by Belcher et al. (2021), who argue that alteration of fire feedbacks driven by the rise of the flowering plants likely lowered atmospheric oxygen levels from ~30% to 25% by the end of the Cretaceous. • White & Campione (2021) describe a workflow in which three-dimensional surface profiles of fragmentary fossils can be quantitatively compared to better-known exemplars in order to identify fragmentary fossils, and apply this workflow to
megaraptorid theropod unguals from the Cretaceous of Australia. • A study aiming to test whether
histological characters can be used to assign bones to individuals within a quarry, using
sauropod dinosaur material from two adjacent
Morrison quarries in the
Bighorn Basin (
Wyoming, United States) as a case study, is published by Wiersma-Weyand et al. (2021). • A study on diverse
amniotic eggshells from the Wido Volcanics (Upper Cretaceous,
South Korea), evaluating their utility for assessments of the
paleothermometry of the sedimentary deposits, is published by Choi et al. (2021). • A study on the age and duration of the Lower Cretaceous
Yixian Formation (China) is published by Zhong et al. (2021). • A study on the age of the
Jiufotang Formation outcrops in the Jianchang Basin (Liaoning, China) is published by Yu et al. (2021). • A study on the elevation and mean annual temperature of the Sihetun area (Liaoning, China) in the Early Cretaceous, when the area was inhabited by feathered dinosaurs, is published by Zhang, Yin & Wang (2021), who interpret their findings as indicative of a high altitude and cold habitat with frozen winters for the Jehol Biota in this area, and evaluate possible implications of such habitat for the evolution of the feathered characteristic of the dinosaurs. • A study on possible impact of
taphonomic biases on preservation of small-bodied dinosaurs and mammals from the
Hell Creek and
Lance formations, and on its implications for the knowledge of diversity and abundance of small-bodied taxa from these formations, is published by Brown et al. (2021). • Goderis et al. (2021) report new data revealing a positive
iridium anomaly within the peak-ring sequence of the
Chicxulub impact structure, and interpret this finding as conclusively tying Chicxulub to the global iridium layer and Cretaceous-Paleogene boundary sections worldwide, confirming the link between crater formation and the iridium peak detected in these sections. • DePalma et al. (2021) present data from histological and histo-isotopic analyses of fossil fish from the
Tanis fossil site (
North Dakota, United States), interpreted as indicating that the end-Cretaceous Chicxulub impact occurred during boreal Spring/Summer, shortly after the spawning season for fish and most continental taxa. • A study on the
taphonomy of marine vertebrate fossils from the Miocene
Pisco Formation (
Peru), aiming to determine possible causes of their exceptional preservation, is published by Bosio et al. (2021). • A study on Middle Miocene microfloral assemblages from ten localities in the Madrid Basin (Spain), providing evidence of prevalence of open habitats with grass-dominated, savannah-like vegetation under a warm and semi-arid climatic regime in the Iberian Peninsula in the Middle Miocene, is published by Casas-Gallego et al. (2021). • A study aiming to determine whether a strong link can be established between stable carbon isotopes of tooth enamel of herbivores and vegetation structure in present African ecosystems, and whether enamel stable carbon isotopes of fossil herbivores are useful for making inferences about Plio-Pleistocene vegetation structure in Africa and the environmental context of hominin evolution, is published by Robinson et al. (2021). • A study on environmental changes in East Africa at the time of the extinction of
Paranthropus boisei is published by Quinn & Lepre (2021), who report evidence of a significant reduction in
C4 grasslands during
Mid-Pleistocene Transition, and argue that this reduction might have escalated dietary competition amongst the abundant C4-feeders and influenced
P. boisei demise; their conclusions are subsequently contested by Patterson et al. (2022). • Evidence from
Chitimwe Beds (northern
Malawi), indicating that in the late Pleistocene early modern humans fundamentally altered local landscapes and ecology using fire, is presented by Thompson et al. (2021). • A study on the climate and environments in the Guadix-Baza Basin (Spain) from the Pliocene to the Middle Pleistocene, aiming to reconstruct environments inhabited by some of the earliest humans who dispersed into Europe, is published by Saarinen et al. (2021). • A study on the Early Pleistocene environment of the
Nihewan Basin (China), as indicated by stable isotope data from tooth enamel of mammals from the Madigou site, is published by Xu et al. (2021). • A study on environmental changes in Southeast Asia at the time of the Pleistocene turnovers of hominin species culminating with the arrival of
Homo sapiens in the area, based on data from mammal fossils from five faunas from
Vietnam and
Laos whose ages ranged from
MIS 6–5 to MIS 3–2, and aiming to determine how the climate changes that occurred during the Late Pleistocene might have influenced the adaptation of the first
H. sapiens in the area, is published by Bacon et al. (2021). • A study on the relationship between the severity of late Quaternary megaherbivore extinctions and fire activity in grassy ecosystems is published by Karp et al. (2021). • Ellis et al. (2021) examine current biodiversity patterns in relation to distribution of human populations and land use over the past 12,000 years, and argue that as early as 12,000 years ago nearly three quarters of Earth's land was inhabited and shaped by human societies. • Alleon et al. (2021) revise reports of organic molecules in animal fossils, and argue that purported signatures of organic molecules are in reality instrumental artefacts resulting from intense background luminescence; their conclusions are subsequently contested by Wiemann &
Briggs (2022). • A study aiming to assess how methods used to determine diversification rate variation through time perform when applied to entirely extinct groups, applying them to
ornithischian dinosaurs, is published by Černý, Madzia & Slater (2021). • A new method for estimating dimorphism levels in fossil assemblages is presented by Sasaki et al. (2021). • A methodological schema for investigating
evolvability in the fossil record is proposed by Love et al. (2021). • Didier &
Laurin (2021) present a method to compute the distribution of the extinction time of a given set of taxa, and apply this method to the study of the extinction time of three Permo-Carboniferous synapsid taxa (
Ophiacodontidae,
Edaphosauridae and
Sphenacodontidae). • A study assessing whether resin impregnation of sediment blocks interferes with the retrieval of ancient DNA from sediments, and evaluating ancient mammalian DNA preservation in Pleistocene sediment blocks from 13 archaeological sites in Europe, Asia, Africa, and North America, is published by Massilani et al. (2021). • A study exploring the causal relationship between the global distribution of fossil occurrence data and the legacy of colonialism and associated socioeconomic factors, and evaluating the implications of that relationships for the knowledge of past biodiversity, is published by Raja et al. (2021).
Paleoclimate •
Scotese et al. (2021) estimate how global temperatures have changed during the last 540 million years. • A high-resolution proxy record of Late Cambrian and Ordovician climate is presented by Goldberg et al. (2021). • A study on changes in weathering intensity and temperature along a temperate to subpolar southeastern margin of
Gondwana (eastern margin of present-day Australia) across the end-Permian extinction is published by Frank et al. (2021). • A study on the atmospheric CO2 levels during the Permian–Triassic transition, based on data from fossil plant remains from sedimentary successions in southwestern China, is published by Wu et al. (2021), who present evidence of a six-fold increase of atmospheric
pCO2 during the Permian–Triassic mass extinction. • A study on the source, pace and total amount of CO2 emissions during the Permian–Triassic transition is published by Cui et al. (2021), who interpret their findings as suggesting that rapid and massive amount of largely volcanic CO2 emission was necessary to drive the observed pattern of carbon isotope excursions, the abrupt decline in surface ocean pH and global temperature increase, and was likely the main cause of the end-Permian mass extinction. • A study on the climate of the Lufeng area (China) during the
Early Jurassic, and on the relationship between the global distribution of dinosaur fossils and climate during the Jurassic, is published by Shen et al. (2021). • A study on atmospheric carbon dioxide concentration levels during the late
Albian, as indicated by
stomata characteristics of conifers
Pseudofrenelopsis gansuensis and
Pseudofrenelopsis dalatzensis from the Dalazi Formation (China), is published by Li, Yang & Zhu (2021). • Evidence of the presence of a terrestrial climate barrier in the Western Interior Basin of North America during the final 15 million years of the Cretaceous, dividing the Western Interior Basin into warm southern and cool northern biomes, is presented by Burgener et al. (2021), who also report evidence indicating that the
biogeographical distribution of plants was heavily influenced by the presence of this temperature transition zone. • De Winter et al. (2021) present reconstructions of monthly
sea surface temperatures at around
50 °N latitude about 78 million years ago, based on data from oyster and
rudist shells from the
Kristianstad Basin (
Sweden). • A study on CO2 contents of early
Deccan Traps lavas, aiming to determine whether early Deccan magmatism triggered the warming event during the latest
Maastrichtian, is published by Hernandez Nava et al. (2021). • Vento et al. (2021) estimate parameters of the
Paleogene to
Neogene climate on the basis of data from fossil leaves from the
Río Turbio and
Río Guillermo formations in southern South America (
Argentina). • A study aiming to evaluate the fit of molecular phylogenetic and
biogeographic data from extant animals and models regarding the age of formation of the
Amazon fluvial system is published by Méndez-Camacho, Leon-Alvarado & Miranda-Esquivel (2021). • 10-million-year long proxy record of Arabian climate is developed by
Böhme et al. (2021), who report evidence indicative of a sustained period of hyperaridity in the Pliocene and a number of transient periods of hyperaridity in northern Arabia during the late Miocene which were out of phase with those in North Africa, and argue that these desert dynamics had a strong control on large-scale mammalian dispersals between Africa and Eurasia. • A study aiming to estimate the tolerance to low precipitation and aridity that would have been required for early humans to successfully exit Africa and to determine the timings of climatic windows out of Africa for humans, based on data from paleoclimate simulations of the last 300,000 years, is published by Beyer et al. (2021). • A study on climate changes in eastern Africa over the past 200,000 years, evaluating their possible impact on the mobility and dispersal of early
Homo sapiens, is published by Schaebitz et al. (2021). • A study aiming to reconstruct summer and winter temperatures in the Late Pleistocene when
Neanderthals were using the site of
La Ferrassie (
France), based on data from oxygen isotope measurements of bovid
tooth enamel, is published by Pederzani et al. (2021). • A study on local seasonal temperatures in the area of the
Bacho Kiro cave (
Bulgaria) in the Initial
Upper Paleolithic, and on its implications for the knowledge whether early presence of
Homo sapiens in Europe was contingent on warm climates, is published by Pederzani et al. (2021). • Data from analyses and modelling of noble gases in groundwater, indicating that the low-altitude, low-to-mid-latitude land surface (
45 degrees south to
35 degrees north) was about 6 °C cooler during the
Last Glacial Maximum than during the Late Holocene, is presented by Seltzer et al. (2021). • Osman et al. (2021) reconstruct surface temperature changes spanning the Last Glacial Maximum to present at 200-year resolution. ==References==