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Megafauna are ecologically important. They are ecosystem engineers that substantially modify modern ecosystems, and likely did so for prehistoric ecosystems prior to the Late Quaternary extinction (LQE) event as well. The LQE resulted in the loss of ~65% of all large mammals during an age of global climate change and human population expansion. This means that understanding the causes and ecological impacts of megafauna preceding, during, and following the LQE is important for better understanding megafauna ecology and conservation today.To further this understanding, here I 1) explore the developing body of indicators used for inferring historic and prehistoric megafauna abundances; 2) investigate the environmental conditions surrounding human arrival and megafauna extirpation in Brazil, and; 3) test how sensitive the Sporormiella megafauna indicator is to temperature and humidity, as these factors could confound megafaunal population-size estimates based on Sporormiella abundances.The first chapter reviews the many different population-size indicators used in megafauna paleoecology. and finds all have their pros and cons regarding their applicabilities towards reconstructing megafauna populations depending on the depositional environment and other taphonomic factors. A widely used indicator of relative megafauna population size is the abundance of the dung fungus Sporormiella in sediment records, despite the need for more taphonomic work necessary to more robustly relate spore abundance to megafauna abundance.The second chapter untangles the relationship between climate, vegetation changes, human population growth, and megafauna decline surrounding the LQE in Brazil as a case study. I found that combinations of anthropogenic, climatic, and vegetational changes are likely implicated as causal factors, but the tree factors vary in their importance for different regions of Brazil. However, human population growth prior to the megafauna extirpation stands out as most

Megafauna are ecologically important. They are ecosystem engineers that substantially modify modern ecosystems, and likely did so for prehistoric ecosystems prior to the Late Quaternary extinction (LQE) event as well. The LQE resulted in the loss of ~65% of all large mammals during an age of global climate change and human population expansion. This means that understanding the causes and ecological impacts of megafauna preceding, during, and following the LQE is important for better understanding megafauna ecology and conservation today.To further this understanding, here I 1) explore the developing body of indicators used for inferring historic and prehistoric megafauna abundances; 2) investigate the environmental conditions surrounding human arrival and megafauna extirpation in Brazil, and; 3) test how sensitive the Sporormiella megafauna indicator is to temperature and humidity, as these factors could confound megafaunal population-size estimates based on Sporormiella abundances.The first chapter reviews the many different population-size indicators used in megafauna paleoecology. and finds all have their pros and cons regarding their applicabilities towards reconstructing megafauna populations depending on the depositional environment and other taphonomic factors. A widely used indicator of relative megafauna population size is the abundance of the dung fungus Sporormiella in sediment records, despite the need for more taphonomic work necessary to more robustly relate spore abundance to megafauna abundance.The second chapter untangles the relationship between climate, vegetation changes, human population growth, and megafauna decline surrounding the LQE in Brazil as a case study. I found that combinations of anthropogenic, climatic, and vegetational changes are likely implicated as causal factors, but the tree factors vary in their importance for different regions of Brazil. However, human population growth prior to the megafauna extirpation stands out as most

Background Childhood asthma is a significant public health problem and severe exacerbations can result in diminished quality of life and hospitalization. Objective We sought to examine the contribution of outdoor fungi to childhood and adolescent asthma hospitalizations. Methods The Melbourne Air Pollen Children and Adolescent study is a case-crossover study of 644 children and adolescents (aged 2-17 years) hospitalized for asthma. The Melbourne Air Pollen Children and Adolescent study collected individual data on human rhinovirus infection and sensitization to Alternaria and Cladosporium and daily counts of ambient concentrations of fungal spores, pollen, and air pollutants. Conditional logistic regression models were used to assess associations with increases in spore counts while controlling for potential confounding and testing interactions. Results Exposure to Alternaria (adjusted odds ratio [aOR], 1.07; 95% CI, 1.03-1.11), Leptosphaeria (aOR, 1.05; 95% CI, 1.02-1.07), Coprinus (aOR, 1.04; 95% CI, 1.01-1.07), Drechslera (aOR, 1.03; 95% CI, 1.00-1.05), and total spores (aOR, 1.05; 95% CI, 1.01-1.09) was significantly associated with child asthma hospitalizations independent of human rhinovirus infection. There were significant lagged effects up to 3 days with Alternaria, Leptosphaeria, Cladosporium, Sporormiella, Coprinus, and Drechslera. Some of these associations were significantly greater in participants with Cladosporium sensitization. Conclusions Exposures to several outdoor fungal spore taxa, including some not reported in previous research, are associated with the risk of child and adolescent asthma hospitalization, particularly in individuals sensitized to Cladosporium. We need further studies to examine cross-reactivity causing asthma exacerbations. Identifying sensitization to multiple fungal allergens in children with asthma could support the design and implementation of more effective strategies to prevent asthma exacerbations.Copyright © 2016 Americ

Background Childhood asthma is a significant public health problem and severe exacerbations can result in diminished quality of life and hospitalization. Objective We sought to examine the contribution of outdoor fungi to childhood and adolescent asthma hospitalizations. Methods The Melbourne Air Pollen Children and Adolescent study is a case-crossover study of 644 children and adolescents (aged 2-17 years) hospitalized for asthma. The Melbourne Air Pollen Children and Adolescent study collected individual data on human rhinovirus infection and sensitization to Alternaria and Cladosporium and daily counts of ambient concentrations of fungal spores, pollen, and air pollutants. Conditional logistic regression models were used to assess associations with increases in spore counts while controlling for potential confounding and testing interactions. Results Exposure to Alternaria (adjusted odds ratio [aOR], 1.07; 95% CI, 1.03-1.11), Leptosphaeria (aOR, 1.05; 95% CI, 1.02-1.07), Coprinus (aOR, 1.04; 95% CI, 1.01-1.07), Drechslera (aOR, 1.03; 95% CI, 1.00-1.05), and total spores (aOR, 1.05; 95% CI, 1.01-1.09) was significantly associated with child asthma hospitalizations independent of human rhinovirus infection. There were significant lagged effects up to 3 days with Alternaria, Leptosphaeria, Cladosporium, Sporormiella, Coprinus, and Drechslera. Some of these associations were significantly greater in participants with Cladosporium sensitization. Conclusions Exposures to several outdoor fungal spore taxa, including some not reported in previous research, are associated with the risk of child and adolescent asthma hospitalization, particularly in individuals sensitized to Cladosporium. We need further studies to examine cross-reactivity causing asthma exacerbations. Identifying sensitization to multiple fungal allergens in children with asthma could support the design and implementation of more effective strategies to prevent asthma exacerbations.Copyright © 2016 Americ

Fungi which produce their spores on the dung of large herbivores show promise as indicators of the distribution and relative abundance of large herbivores in past environments. Recently, several studies have used counts of spores of such fungi, Sporormiella in particular, to resolve the timing and reveal the ecological consequences of extinction of Pleistocene megafauna. However, there are several problems in the interpretation of the dung-fungus proxy, relating mostly to taphonomic effects on spore accumulation. Here, we describe these problems and show how they can be solved, using new data from the Lynch's Crater site in northeastern Australia. Effects of variation in spore accumulation in relation to position in the sedimentary basin can be controlled by comparing cores from different locations; temporal variation in spore accumulation rates can be attributed to changes in herbivore populations, as distinct from time-varying taphonomic effects, by comparing trends in fungi exclusively associated with herbivore dung to trends for fungi that also sporulate on other substrates; effects of changing vegetation composition can be removed by measuring spore influx rates rather than expressing counts relative to the pollen sum. At Lynch's Crater, these approaches increase our confidence that a decline in dung fungi at ~40 ka indicates an unprecedented drop in biomass of large herbivores. We also show that before this decline, the biomass of large herbivores at this site was evidently similar to that in North America and western Europe.

The family Sporormiaceae (Pleosporales, Dothideomycetes, Ascomycota) occur worldwide and a majority of the species are coprophilous. The taxonomy and classification of the family are based on a small number of morphological and ecological characters. Several taxa are easily confused by their shared morphological features, and the relationships between genera are poorly known and in need of critical study. The aims of this study were to resolve the phylogenetic relationships within the Sporormiaceae, test the current generic classification, and study the utility of traditional characters for the taxonomy in the group. To resolve these questions, we analysed combined data sets of ITS-nLSU rDNA, mtSSU rDNA and beta-tubulin sequences with parsimony and Bayesian methods. The results showed that many characters, which previously have been used in the taxonomy and classification of the Sporormiaceae, such as the substrate choice, presence or absence of an ostiole, and presence or absence of germ slits, were all homoplastic and not useful for circumscribing monophyletic groups. A number of characters may be useful for circumscribing smaller clades if used in combination with other features, such as the shape of the ascus with the shape of the ascospores. Our phylogenetic analyses show that Preussia and Sporormiella are non-monophyletic, and a constrained analysis forcing these genera into monophyly resulted in significantly worse trees. Spororminula is nested in Preussia s. lat., and Eremodothis and Pycnidiophora are nested within Westerdykella. Finally, we suggest a new generic classification for the family Sporormiaceae, including Sporormia, Preussia (including Sporomiella and Spororminula) and Westerdykella (including Eremodothis and Pycnidiophora). We also propose 14 new combinations: Preussia alloiomera (S.I. Ahmed & Cain) Kruys, Preussia antarctica (Speg.) Kruys, Preussia bipartis (Cain) Kruys, Preussia borealis (I.Egeland) Kruys, Preussia dubia (S.I. Ahmed &