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Harmful algal and bacterial blooms linked to deforestation, soil loss and global warming are increasingly frequent in lakes and rivers. We demonstrate that climate changes and deforestation can drive recurrent microbial blooms, inhibiting the recovery of freshwater ecosystems for hundreds of millennia. From the stratigraphic successions of the Sydney Basin, Australia, our fossil, sedimentary and geochemical data reveal bloom events following forest ecosystem collapse during the most severe mass extinction in Earth’s history, the end-Permian event (EPE; c. 252.2 Ma). Microbial communities proliferated in lowland fresh and brackish waterbodies, with algal concentrations typical of modern blooms. These initiated before any trace of post-extinction recovery vegetation but recurred episodically for >100 kyrs. During the following 3 Myrs, algae and bacteria thrived within short-lived, poorly-oxygenated, and likely toxic lakes and rivers. Comparisons to global deep-time records indicate that microbial blooms are persistent freshwater ecological stressors during warming-driven extinction events. Harmful algal and bacterial blooms are increasingly frequent in lakes and rivers. From the Sydney Basin, Australia, this study uses fossil, sedimentary and geochemical data to reveal bloom events following forest ecosystem collapse during the end-Permian event and that blooms have consistently followed warming-related extinction events, inhibiting the recovery of freshwater ecosystems for millennia.

Past studies of the end-Permian extinction (EPE), the largest biotic crisis of the Phanerozoic, have not resolved the timing of events in southern high-latitudes. Here we use palynology coupled with high-precision CA-ID-TIMS dating of euhedral zircons from continental sequences of the Sydney Basin, Australia, to show that the collapse of the austral Permian Glossopteris flora occurred prior to 252.3 Ma (~370 kyrs before the main marine extinction). Weathering proxies indicate that floristic changes occurred during a brief climate perturbation in a regional alluvial landscape that otherwise experienced insubstantial change in fluvial style, insignificant reorganization of the depositional surface, and no abrupt aridification. Palaeoclimate modelling suggests a moderate shift to warmer summer temperatures and amplified seasonality in temperature across the EPE, and warmer and wetter conditions for all seasons into the Early Triassic. The terrestrial EPE and a succeeding peak in Ni concentration in the Sydney Basin correlate, respectively, to the onset of the primary extrusive and intrusive phases of the Siberian Traps Large Igneous Province. The continental record of the end Permian mass extinction is limited, especially from high paleolatitudes. Here, Fielding et al. report a multi-proxy Permo-Triassic record from Australia, resolving the timing of local terrestrial plant extinction and the relationship with environmental changes.

While rhetoric as a discipline is firmly planted in humanism and anthropology, posthumanism seeks to leave the human behind. This highly original examination of Kenneth Burke's thought grapples with these ostensibly contradictory concepts as opportunities for invention, revision, and, importantly, transdisciplinary knowledge making. Rather than simply mapping posthumanist rhetorics onto Burke's scholarship, Kenneth Burke + The Posthuman focuses on the multiplicity of ideas found both in his work and in the idea of posthumanism. Taking varied approaches organized within a framework of boundaries and futures, the contributors show that studying the humanist theories of Burke in this way creates a satisfyingly chaotic web of interconnections. The essays look at how Burke's writing on the human mind and technology, from his earliest works to his very latest revisions, interrelates with current concepts such as new materiality and coevolution. Throughout, the contributors pay close attention to the fluidity, concerns, and contradictions inherent in language, symbolism, and subjectivity. A unique, illuminating exploration of the contested relationship between bodies and language, this inherently transdisciplinary book will propel important future inquiry by scholars of rhetoric, Burke, and posthumanism. In addition to the editors, the contributors are Casey Boyle, Kristie Fleckenstein, Nathan Gale, Julie Jung, Steven B. Katz, Steven LeMieux, Jodie Nicotra, Jeff Pruchnic, Timothy Richardson, Thomas Rickert, and Robert Wess.

Previously unrecognized anatomical features of the cone scales of the enigmatic Early Cretaceous conifer Krassilovia mongolica include the presence of transversely oriented paracytic stomata, which is unusual for all other extinct and extant conifers. Identical stomata are present on co-occurring broad, linear, multiveined leaves assigned to Podozamites harrisii, providing evidence that K. mongolica and P. harrisii are the seed cones and leaves of the same extinct plant. Phylogenetic analyses of the relationships of the reconstructed Krassilovia plant place it in an informal clade that we name the Krassilovia Clade, which also includes Swedenborgia cryptomerioides-Podozamites schenkii, and Cycadocarpidium erdmanni-Podozamites schenkii. All three of these plants have linear leaves that are relatively broad compared to most living conifers, and that are also multiveined with transversely oriented paracytic stomata. We propose that these may be general features of the Krassilovia Clade. Paracytic stomata, and other features of this new group, recall features of extant and fossil Gnetales, raising questions about the phylogenetic homogeneity of the conifer clade similar to those raised by phylogenetic analyses of molecular data.

This paper argues that ignorance, rather than being a result or representation of false beliefs or misinformation, is a compensatory epistemic adaptation of complex rhetoric systems. A rhetoric system is here defined as a set of interconnected rhetorical elements (beliefs, arguments, commonplaces [loci communes], meanings, and texts) that cohere into a self-organized system that is thoroughly “about” its contexts—meaning that its own boundaries and relations are both constrained and enabled by the contexts in which it exists. Ignorance, as described here, is epistemic management that preserves the boundaries and relations of a rhetoric system, and is a way of dealing with information that runs counter to one’s beliefs. Ignorance is also productive, in that it produces new knowledge that works to make rhetoric systems more resistant to potential destabilization. To elaborate these points, the paper examines discourse about the phenomenon of global climate change, which illustrates how individuals productively counter information as a way of preserving beliefs. As the paper argues, ignorance is neither a cognitive nor epistemological failure, but rather is a result of the dynamic and continuous process of enforcing epistemic and rhetorical boundaries.

Key parameters of biological systems—e.g., productivity, population sizes, biomass—are best expressed as absolute values. Exotic markers (e.g., Lycopodium spores introduced into microfossil populations) have long been used to estimate population sizes from representative samples. However, the traditional approach—the ‘linear method’ herein—can be extremely time consuming and impractical for routine use. Here, we present a new variant of this technique: the ‘field-of-view subsampling method’ (FOVS method). This new method requires a few simple, easily obtainable statistical parameters, beyond the standard inputs for the traditional linear method. The FOVS method adds error from sample heterogeneity, but enables the collection of very large sample sizes with low additional effort. We compared the FOVS and linear methods with two case studies: 1, Monte Carlo simulations to validate the methods with idealised datasets; and 2, terrestrial organic microfossils from Permian–Triassic rock strata in southeastern Australia as ‘real-world’ empirical datasets. Three output parameters were measured: 1, absolute abundance; 2, precision (=error rate); and 3, data collection effort (typically, this translates to data collection time). The linear method showed superior efficiency only for assemblages with very low specimen densities and/or near-equivalent target-to-marker ratios, conditions we predict are rare under real-world conditions. In contrast, the FOVS method provided greater precision and/or reduced effort under almost all conditions, without sacrificing accuracy. Although originally developed for microfossils, the new method may apply to any spatial data collection where markers of known quantity can be introduced to a population. Given its demonstrable increased speed and precision, we recommend the FOVS method as the new standard for such absolute abundance estimates. Guidelines and a user-friendly digital interface for implementing both of these count methods are provided, in addition to simulation codes aimed to assist readers in designing their own experiments.

A new Turonian amber occurrence, representing the oldest in situ amber locality in Australia and the southern-most locality in Gondwana, has recently been discovered in the Otway Basin of Victoria. The amber was collected from petroleum cores and many pieces contain a range of inclusions that can provide information on the depositional history of the resin. To date, one species of fern spore (Cyathidites minor) and one species of lycophyte spore (Kraeuselisporites sp?) have been conclusively identified in the amber, along with filamentous microorganisms and degraded plant matter. Several samples are also rife with pseudoinclusions as reported recently in other ambers. The abundance of preserved particulate debris and wind dispersed spores suggest that the Otway amber formed subaerially. Furthermore, based on the range of bioinclusions and forms of pseudoinclusions preserved within a single piece of amber, the locus of hardening for individual samples is variably interpreted as occurring in the tree tops, on the tree trunk or on the ground surface. Notably, specific inclusion assemblages are associated with certain colours of amber. By extension, and in accordance with recent studies, amber colour may be indicative of depositional environment. Variation in the environment of solidification may, therefore, be sufficient to account for the broad range of morphological characteristics preserved in a single amber deposit.

This article uses systems and complexity theory to illustrate key characteristics of writing as a complex system. This illustration reveals how writing works on multiple levels of scale, and adds to the body of theoretical knowledge that can be taught within the discipline of writing studies. In so doing, it shows how a complex systems writing pedagogy can benefit both researchers and students.

Jim W. Corder, writing over thirty years ago, explained that we all create the narrative that is our lives. The difficulty, Corder writes, comes in accommodating the divergent narratives of others. On first glance, asserting that writing is complex might not seem to be putting forth a groundbreaking premise. In the past few years, writing studies scholarship has extensively explored writing's complexity and exposed several significant and far-reaching ramifications of this idea. As many have also noted, writing's complexity also gives it a significant power to interact with and shape our world. In this sense, we can understand writing as complex in both its form and function, with subtle discursive constructions generating profound effects on the local reader and in the wider environment. Writing can evoke powerful thoughts and compel drastic actions, it can produce a powerful unity or kinship with an author, and it can create entirely new perceptions of the world; it may do all of this across an entire text or within a single sentence.

Premise of research. Permineralized peats are prized for hosting three-dimensionally preserved plant remains that provide insights into fossil plant anatomy and the composition of coal-forming ecosystems. A new record of siliceous permineralized peat is documented from a Lopingian-aged (upper Permian) strata from the southern Sydney Basin. It represents the fifth Permian permineralized peat identified from eastern Australia. Methodology. The single permineralized peat block was cut into smaller blocks, and both cellulose acetate peels and standard thin sections were prepared for study using transmitted light microscopy. Quantitative analysis of the peat was carried out using point counts perpendicular to bedding. One block examined using synchrotron X-ray computed tomography (CT) revealed the three-dimensional anatomy of abundant fossil seeds. Pivotal results. The peat contains a plant assemblage dominated by glossopterid leaves, seeds, and axes; although degraded, probable pteridophyte remains represent a significant subsidiary component of the assemblage. A new leaf form (Glossopteris thirroulensis McLoughlin et Mays sp. nov.) and a new type of seed (Illawarraspermum ovatum McLoughlin et Mays gen. et sp. nov.) are described. Leaf-, wood/seed-, and fine detritus-rich organic microfacies with gradational boundaries are evident within the peat. Conclusions. Regular growth rings in the small permineralized axes, together with the occurrence of autumnal mats of glossopterid leaves, signify a strongly seasonal climate. The presence of abundant charcoal in the peat indicates that fire was a significant influence on the high-paleolatitude mire ecosystem. Differentiation of organic microfacies within the peat profile indicates subtle variation in the contribution of plant components to the peat through time. The absence of mineral grains in thin section and CT, together with the presence of authigenic sulfides, indicates accumulation of organic matter in a stagnant mire away from the influence of clastic input.