The acanthodians were a common and widespread group of fishes throughout the world during the mid-Palaeozoic. In this study, a full-scale systematic analysis of Silurian to Middle Devonian acanthodian taxa of eastern Australia was undertaken, incorporating a review and updating of historical records and descriptions of taxa. Phylogenetic relationships within the group and with other early gnathostomes are uncertain. The structure, function and modes of growth of acanthodian scales were described and investigated, and these features were used for comparisons between different taxa within the group, and between acanthodians and other early vertebrates. Histological and morphological characters of the scales were incorporated in a cladistic analysis of genera erected for articulated fish. This analysis did not support the traditional ordinal level groups, the Climatiida, Ischnacanthida and Acanthodida. Therefore, the highest taxonomic level used in the study was the family. Rarely were acanthodians preserved as articulated fossils. The only examples known from the Silurian-Middle Devonian of Australia are one specimen of the putative acanthodian Yealepis douglasi Burrow & Young 1999 from the Ludlow of Victoria, five specimens of an indeterminate ?ischnacanthidid from the late Givetian of New South Wales and a rich assemblage from the Givetian lacustrine shales of Mt Howitt, Victoria. The latter fauna (originally dated as Late Devonian) includes six incomplete specimens of the culmacanthidid Culmacanthus stewarti Long 1983 and about 60 specimens of acanthodidid Howittacanthus kentoni Long 1986. In contrast, disassociated remains of the group are ubiquitous in microvertebrate faunas from the mid-Palaeozoic of eastern Australia. Although scales of other fish groups are sometimes more common in particular facies, acanthodian elements are found in all depositional environments, from deep shelf marine to transitional to freshwater. Most of the taxa, particularly those only preserved as isolated scales, had not been systematically described by other workers. This thesis incorporates descriptions of new taxa, and revision and updating of other taxa. Several overseas studies have produced biostratigraphic charts based on acanthodian scales. A similar biostratigraphic overview was undertaken based on a systematic analysis of the Early Devonian acanthodians of eastern Australia, permitting comparisons with acanthodian faunas of other regions. Acanthodian scales and fin spines are the most common elements in the few vertebrate faunas that are known from the Silurian of Australia. Diversity and geographic distribution of the acanthodian faunas peaked during the Early Devonian. This study has been hampered by the low numbers of scales in many samples, and by uncertainty over their dating (particularly for the faunas from non-limestone deposits). Nevertheless, the work shows that changes in the marine assemblages are broadly correlated with the pattern of marine transgressions and regressions. Composition of the acanthodian faunas, and their abundance relative to other vertebrates in the assemblages, depend on the depositional environment. This correlation is best illustrated in Lower Devonian deposits, in which acanthodians are the most prolific and diverse. In transitional and marginal marine deposits, thelodonts are dominant, and acanthodians a minor element of the fauna. In off-shore assemblages, acanthodians and placoderms are dominant, and thelodonts are rare or absent. Vertebrate faunas are poor in the earliest Devonian deposits, but become more common by the late Lochkovian, with near-shore assemblages characterized by Trundlelepis cervicostulata and ANostolepis@ guangxiensis, and deeper shelf assemblages by a new genus, possibly assignable to the Ischnacanthidae. The vertebrate record is sparse through the middle Pragian, though AN.@ guangxiensis is present low in the Coopers Creek Limestone (upper sulcatus-pireneae zones), being replaced by Nostolepoides platymarginata, Gomphonchus? bogongensis, and Radioporacanthodes sp. aff. R. (Gomphonchus) liujingensis by the kindlei Zone. Microvertebrate assemblages are more common by the late Pragian (pireneae Zone), with Radioporacanthodes sp. aff. R. liujingensis in deeper shelf deposits, and N. platymarginata and G.? bogongensis dominating near-shore assemblages. The earliest Emsian (dehiscens Zone) is marked by the incoming Cheiracanthoides wangi. Middle Emsian (perbonus-serotinus zones) assemblages are characterized by two new species, possibly assignable to Gomphonchus.The Middle Devonian cosmopolitan association of Cheiracanthoides comptus and AAcanthoides@ dublinensis, which characterizes early Middle Devonian faunas from North America, Europe and China, appears first in the latest Emsian at the serotinus-patulus zone boundary. As well as showing the value of acanthodians in biostratigraphy and as indicators of environmental settings, their use in biogeography was demonstrated. Although many of the acanthodian taxa are endemic, several are also found in other regions. The Silurian to earliest Devonian faunas of eastern Australia are most closely related to coeval Chinese assemblages. Several latest Silurian-earliest Devonian taxa are also recorded from the circum-Arctic region. The late Lochkovian to early Emsian assemblages, particularly from south-eastern Australia, have many taxa in common with Chinese faunas. The mid-Emsian taxa show highest endemicity; and the latest Emsian-Eifelian assemblages have the most cosmopolitan aspect. Acanthodian faunas become rarer and depauperate in the Middle Devonian, particularly in the south-eastern corner, and are mostly in poorly dated, ?fluviatile/marginal marine deposits. This study of acanthodian faunas has encompassed a full scale systematic review of the group in this region, an appraisal of phylogenetic relationships within the group and with other early vertebrates, their palaeoecology, and their use in biostratigraphy and biogeography.

The acanthodians were a common and widespread group of fishes throughout the world during the mid-Palaeozoic. In this study, a full-scale systematic analysis of Silurian to Middle Devonian acanthodian taxa of eastern Australia was undertaken, incorporating a review and updating of historical records and descriptions of taxa. Phylogenetic relationships within the group and with other early gnathostomes are uncertain. The structure, function and modes of growth of acanthodian scales were described and investigated, and these features were used for comparisons between different taxa within the group, and between acanthodians and other early vertebrates. Histological and morphological characters of the scales were incorporated in a cladistic analysis of genera erected for articulated fish. This analysis did not support the traditional ordinal level groups, the Climatiida, Ischnacanthida and Acanthodida. Therefore, the highest taxonomic level used in the study was the family. Rarely were acanthodians preserved as articulated fossils. The only examples known from the Silurian-Middle Devonian of Australia are one specimen of the putative acanthodian Yealepis douglasi Burrow & Young 1999 from the Ludlow of Victoria, five specimens of an indeterminate ?ischnacanthidid from the late Givetian of New South Wales and a rich assemblage from the Givetian lacustrine shales of Mt Howitt, Victoria. The latter fauna (originally dated as Late Devonian) includes six incomplete specimens of the culmacanthidid Culmacanthus stewarti Long 1983 and about 60 specimens of acanthodidid Howittacanthus kentoni Long 1986. In contrast, disassociated remains of the group are ubiquitous in microvertebrate faunas from the mid-Palaeozoic of eastern Australia. Although scales of other fish groups are sometimes more common in particular facies, acanthodian elements are found in all depositional environments, from deep shelf marine to transitional to freshwater. Most of the taxa, particularly those only preserved as isolated scales, had not been systematically described by other workers. This thesis incorporates descriptions of new taxa, and revision and updating of other taxa. Several overseas studies have produced biostratigraphic charts based on acanthodian scales. A similar biostratigraphic overview was undertaken based on a systematic analysis of the Early Devonian acanthodians of eastern Australia, permitting comparisons with acanthodian faunas of other regions. Acanthodian scales and fin spines are the most common elements in the few vertebrate faunas that are known from the Silurian of Australia. Diversity and geographic distribution of the acanthodian faunas peaked during the Early Devonian. This study has been hampered by the low numbers of scales in many samples, and by uncertainty over their dating (particularly for the faunas from non-limestone deposits). Nevertheless, the work shows that changes in the marine assemblages are broadly correlated with the pattern of marine transgressions and regressions. Composition of the acanthodian faunas, and their abundance relative to other vertebrates in the assemblages, depend on the depositional environment. This correlation is best illustrated in Lower Devonian deposits, in which acanthodians are the most prolific and diverse. In transitional and marginal marine deposits, thelodonts are dominant, and acanthodians a minor element of the fauna. In off-shore assemblages, acanthodians and placoderms are dominant, and thelodonts are rare or absent. Vertebrate faunas are poor in the earliest Devonian deposits, but become more common by the late Lochkovian, with near-shore assemblages characterized by Trundlelepis cervicostulata and ANostolepis@ guangxiensis, and deeper shelf assemblages by a new genus, possibly assignable to the Ischnacanthidae. The vertebrate record is sparse through the middle Pragian, though AN.@ guangxiensis is present low in the Coopers Creek Limestone (upper sulcatus-pireneae zones), being replaced by Nostolepoides platymarginata, Gomphonchus? bogongensis, and Radioporacanthodes sp. aff. R. (Gomphonchus) liujingensis by the kindlei Zone. Microvertebrate assemblages are more common by the late Pragian (pireneae Zone), with Radioporacanthodes sp. aff. R. liujingensis in deeper shelf deposits, and N. platymarginata and G.? bogongensis dominating near-shore assemblages. The earliest Emsian (dehiscens Zone) is marked by the incoming Cheiracanthoides wangi. Middle Emsian (perbonus-serotinus zones) assemblages are characterized by two new species, possibly assignable to Gomphonchus.The Middle Devonian cosmopolitan association of Cheiracanthoides comptus and AAcanthoides@ dublinensis, which characterizes early Middle Devonian faunas from North America, Europe and China, appears first in the latest Emsian at the serotinus-patulus zone boundary. As well as showing the value of acanthodians in biostratigraphy and as indicators of environmental settings, their use in biogeography was demonstrated. Although many of the acanthodian taxa are endemic, several are also found in other regions. The Silurian to earliest Devonian faunas of eastern Australia are most closely related to coeval Chinese assemblages. Several latest Silurian-earliest Devonian taxa are also recorded from the circum-Arctic region. The late Lochkovian to early Emsian assemblages, particularly from south-eastern Australia, have many taxa in common with Chinese faunas. The mid-Emsian taxa show highest endemicity; and the latest Emsian-Eifelian assemblages have the most cosmopolitan aspect. Acanthodian faunas become rarer and depauperate in the Middle Devonian, particularly in the south-eastern corner, and are mostly in poorly dated, ?fluviatile/marginal marine deposits. This study of acanthodian faunas has encompassed a full scale systematic review of the group in this region, an appraisal of phylogenetic relationships within the group and with other early vertebrates, their palaeoecology, and their use in biostratigraphy and biogeography.

The acanthodians were a common and widespread group of fishes throughout the world during the mid-Palaeozoic. In this study, a full-scale systematic analysis of Silurian to Middle Devonian acanthodian taxa of eastern Australia was undertaken, incorporating a review and updating of historical records and descriptions of taxa. Phylogenetic relationships within the group and with other early gnathostomes are uncertain. The structure, function and modes of growth of acanthodian scales were described and investigated, and these features were used for comparisons between different taxa within the group, and between acanthodians and other early vertebrates. Histological and morphological characters of the scales were incorporated in a cladistic analysis of genera erected for articulated fish. This analysis did not support the traditional ordinal level groups, the Climatiida, Ischnacanthida and Acanthodida. Therefore, the highest taxonomic level used in the study was the family. Rarely were acanthodians preserved as articulated fossils. The only examples known from the Silurian-Middle Devonian of Australia are one specimen of the putative acanthodian Yealepis douglasi Burrow & Young 1999 from the Ludlow of Victoria, five specimens of an indeterminate ?ischnacanthidid from the late Givetian of New South Wales and a rich assemblage from the Givetian lacustrine shales of Mt Howitt, Victoria. The latter fauna (originally dated as Late Devonian) includes six incomplete specimens of the culmacanthidid Culmacanthus stewarti Long 1983 and about 60 specimens of acanthodidid Howittacanthus kentoni Long 1986. In contrast, disassociated remains of the group are ubiquitous in microvertebrate faunas from the mid-Palaeozoic of eastern Australia. Although scales of other fish groups are sometimes more common in particular facies, acanthodian elements are found in all depositional environments, from deep shelf marine to transitional to freshwater. Most of the taxa, particularly those only preserved as isolated scales, had not been systematically described by other workers. This thesis incorporates descriptions of new taxa, and revision and updating of other taxa. Several overseas studies have produced biostratigraphic charts based on acanthodian scales. A similar biostratigraphic overview was undertaken based on a systematic analysis of the Early Devonian acanthodians of eastern Australia, permitting comparisons with acanthodian faunas of other regions. Acanthodian scales and fin spines are the most common elements in the few vertebrate faunas that are known from the Silurian of Australia. Diversity and geographic distribution of the acanthodian faunas peaked during the Early Devonian. This study has been hampered by the low numbers of scales in many samples, and by uncertainty over their dating (particularly for the faunas from non-limestone deposits). Nevertheless, the work shows that changes in the marine assemblages are broadly correlated with the pattern of marine transgressions and regressions. Composition of the acanthodian faunas, and their abundance relative to other vertebrates in the assemblages, depend on the depositional environment. This correlation is best illustrated in Lower Devonian deposits, in which acanthodians are the most prolific and diverse. In transitional and marginal marine deposits, thelodonts are dominant, and acanthodians a minor element of the fauna. In off-shore assemblages, acanthodians and placoderms are dominant, and thelodonts are rare or absent. Vertebrate faunas are poor in the earliest Devonian deposits, but become more common by the late Lochkovian, with near-shore assemblages characterized by Trundlelepis cervicostulata and ANostolepis@ guangxiensis, and deeper shelf assemblages by a new genus, possibly assignable to the Ischnacanthidae. The vertebrate record is sparse through the middle Pragian, though AN.@ guangxiensis is present low in the Coopers Creek Limestone (upper sulcatus-pireneae zones), being replaced by Nostolepoides platymarginata, Gomphonchus? bogongensis, and Radioporacanthodes sp. aff. R. (Gomphonchus) liujingensis by the kindlei Zone. Microvertebrate assemblages are more common by the late Pragian (pireneae Zone), with Radioporacanthodes sp. aff. R. liujingensis in deeper shelf deposits, and N. platymarginata and G.? bogongensis dominating near-shore assemblages. The earliest Emsian (dehiscens Zone) is marked by the incoming Cheiracanthoides wangi. Middle Emsian (perbonus-serotinus zones) assemblages are characterized by two new species, possibly assignable to Gomphonchus.The Middle Devonian cosmopolitan association of Cheiracanthoides comptus and AAcanthoides@ dublinensis, which characterizes early Middle Devonian faunas from North America, Europe and China, appears first in the latest Emsian at the serotinus-patulus zone boundary. As well as showing the value of acanthodians in biostratigraphy and as indicators of environmental settings, their use in biogeography was demonstrated. Although many of the acanthodian taxa are endemic, several are also found in other regions. The Silurian to earliest Devonian faunas of eastern Australia are most closely related to coeval Chinese assemblages. Several latest Silurian-earliest Devonian taxa are also recorded from the circum-Arctic region. The late Lochkovian to early Emsian assemblages, particularly from south-eastern Australia, have many taxa in common with Chinese faunas. The mid-Emsian taxa show highest endemicity; and the latest Emsian-Eifelian assemblages have the most cosmopolitan aspect. Acanthodian faunas become rarer and depauperate in the Middle Devonian, particularly in the south-eastern corner, and are mostly in poorly dated, ?fluviatile/marginal marine deposits. This study of acanthodian faunas has encompassed a full scale systematic review of the group in this region, an appraisal of phylogenetic relationships within the group and with other early vertebrates, their palaeoecology, and their use in biostratigraphy and biogeography.

The acanthodians were a common and widespread group of fishes throughout the world during the mid-Palaeozoic. In this study, a full-scale systematic analysis of Silurian to Middle Devonian acanthodian taxa of eastern Australia was undertaken, incorporating a review and updating of historical records and descriptions of taxa. Phylogenetic relationships within the group and with other early gnathostomes are uncertain. The structure, function and modes of growth of acanthodian scales were described and investigated, and these features were used for comparisons between different taxa within the group, and between acanthodians and other early vertebrates. Histological and morphological characters of the scales were incorporated in a cladistic analysis of genera erected for articulated fish. This analysis did not support the traditional ordinal level groups, the Climatiida, Ischnacanthida and Acanthodida. Therefore, the highest taxonomic level used in the study was the family. Rarely were acanthodians preserved as articulated fossils. The only examples known from the Silurian-Middle Devonian of Australia are one specimen of the putative acanthodian Yealepis douglasi Burrow & Young 1999 from the Ludlow of Victoria, five specimens of an indeterminate ?ischnacanthidid from the late Givetian of New South Wales and a rich assemblage from the Givetian lacustrine shales of Mt Howitt, Victoria. The latter fauna (originally dated as Late Devonian) includes six incomplete specimens of the culmacanthidid Culmacanthus stewarti Long 1983 and about 60 specimens of acanthodidid Howittacanthus kentoni Long 1986. In contrast, disassociated remains of the group are ubiquitous in microvertebrate faunas from the mid-Palaeozoic of eastern Australia. Although scales of other fish groups are sometimes more common in particular facies, acanthodian elements are found in all depositional environments, from deep shelf marine to transitional to freshwater. Most of the taxa, particularly those only preserved as isolated scales, had not been systematically described by other workers. This thesis incorporates descriptions of new taxa, and revision and updating of other taxa. Several overseas studies have produced biostratigraphic charts based on acanthodian scales. A similar biostratigraphic overview was undertaken based on a systematic analysis of the Early Devonian acanthodians of eastern Australia, permitting comparisons with acanthodian faunas of other regions. Acanthodian scales and fin spines are the most common elements in the few vertebrate faunas that are known from the Silurian of Australia. Diversity and geographic distribution of the acanthodian faunas peaked during the Early Devonian. This study has been hampered by the low numbers of scales in many samples, and by uncertainty over their dating (particularly for the faunas from non-limestone deposits). Nevertheless, the work shows that changes in the marine assemblages are broadly correlated with the pattern of marine transgressions and regressions. Composition of the acanthodian faunas, and their abundance relative to other vertebrates in the assemblages, depend on the depositional environment. This correlation is best illustrated in Lower Devonian deposits, in which acanthodians are the most prolific and diverse. In transitional and marginal marine deposits, thelodonts are dominant, and acanthodians a minor element of the fauna. In off-shore assemblages, acanthodians and placoderms are dominant, and thelodonts are rare or absent. Vertebrate faunas are poor in the earliest Devonian deposits, but become more common by the late Lochkovian, with near-shore assemblages characterized by Trundlelepis cervicostulata and ANostolepis@ guangxiensis, and deeper shelf assemblages by a new genus, possibly assignable to the Ischnacanthidae. The vertebrate record is sparse through the middle Pragian, though AN.@ guangxiensis is present low in the Coopers Creek Limestone (upper sulcatus-pireneae zones), being replaced by Nostolepoides platymarginata, Gomphonchus? bogongensis, and Radioporacanthodes sp. aff. R. (Gomphonchus) liujingensis by the kindlei Zone. Microvertebrate assemblages are more common by the late Pragian (pireneae Zone), with Radioporacanthodes sp. aff. R. liujingensis in deeper shelf deposits, and N. platymarginata and G.? bogongensis dominating near-shore assemblages. The earliest Emsian (dehiscens Zone) is marked by the incoming Cheiracanthoides wangi. Middle Emsian (perbonus-serotinus zones) assemblages are characterized by two new species, possibly assignable to Gomphonchus.The Middle Devonian cosmopolitan association of Cheiracanthoides comptus and AAcanthoides@ dublinensis, which characterizes early Middle Devonian faunas from North America, Europe and China, appears first in the latest Emsian at the serotinus-patulus zone boundary. As well as showing the value of acanthodians in biostratigraphy and as indicators of environmental settings, their use in biogeography was demonstrated. Although many of the acanthodian taxa are endemic, several are also found in other regions. The Silurian to earliest Devonian faunas of eastern Australia are most closely related to coeval Chinese assemblages. Several latest Silurian-earliest Devonian taxa are also recorded from the circum-Arctic region. The late Lochkovian to early Emsian assemblages, particularly from south-eastern Australia, have many taxa in common with Chinese faunas. The mid-Emsian taxa show highest endemicity; and the latest Emsian-Eifelian assemblages have the most cosmopolitan aspect. Acanthodian faunas become rarer and depauperate in the Middle Devonian, particularly in the south-eastern corner, and are mostly in poorly dated, ?fluviatile/marginal marine deposits. This study of acanthodian faunas has encompassed a full scale systematic review of the group in this region, an appraisal of phylogenetic relationships within the group and with other early vertebrates, their palaeoecology, and their use in biostratigraphy and biogeography.

The acanthodians were a common and widespread group of fishes throughout the world during the mid-Palaeozoic. In this study, a full-scale systematic analysis of Silurian to Middle Devonian acanthodian taxa of eastern Australia was undertaken, incorporating a review and updating of historical records and descriptions of taxa. Phylogenetic relationships within the group and with other early gnathostomes are uncertain. The structure, function and modes of growth of acanthodian scales were described and investigated, and these features were used for comparisons between different taxa within the group, and between acanthodians and other early vertebrates. Histological and morphological characters of the scales were incorporated in a cladistic analysis of genera erected for articulated fish. This analysis did not support the traditional ordinal level groups, the Climatiida, Ischnacanthida and Acanthodida. Therefore, the highest taxonomic level used in the study was the family. Rarely were acanthodians preserved as articulated fossils. The only examples known from the Silurian-Middle Devonian of Australia are one specimen of the putative acanthodian Yealepis douglasi Burrow & Young 1999 from the Ludlow of Victoria, five specimens of an indeterminate ?ischnacanthidid from the late Givetian of New South Wales and a rich assemblage from the Givetian lacustrine shales of Mt Howitt, Victoria. The latter fauna (originally dated as Late Devonian) includes six incomplete specimens of the culmacanthidid Culmacanthus stewarti Long 1983 and about 60 specimens of acanthodidid Howittacanthus kentoni Long 1986. In contrast, disassociated remains of the group are ubiquitous in microvertebrate faunas from the mid-Palaeozoic of eastern Australia. Although scales of other fish groups are sometimes more common in particular facies, acanthodian elements are found in all depositional environments, from deep shelf marine to transitional to freshwater. Most of the taxa, particularly those only preserved as isolated scales, had not been systematically described by other workers. This thesis incorporates descriptions of new taxa, and revision and updating of other taxa. Several overseas studies have produced biostratigraphic charts based on acanthodian scales. A similar biostratigraphic overview was undertaken based on a systematic analysis of the Early Devonian acanthodians of eastern Australia, permitting comparisons with acanthodian faunas of other regions. Acanthodian scales and fin spines are the most common elements in the few vertebrate faunas that are known from the Silurian of Australia. Diversity and geographic distribution of the acanthodian faunas peaked during the Early Devonian. This study has been hampered by the low numbers of scales in many samples, and by uncertainty over their dating (particularly for the faunas from non-limestone deposits). Nevertheless, the work shows that changes in the marine assemblages are broadly correlated with the pattern of marine transgressions and regressions. Composition of the acanthodian faunas, and their abundance relative to other vertebrates in the assemblages, depend on the depositional environment. This correlation is best illustrated in Lower Devonian deposits, in which acanthodians are the most prolific and diverse. In transitional and marginal marine deposits, thelodonts are dominant, and acanthodians a minor element of the fauna. In off-shore assemblages, acanthodians and placoderms are dominant, and thelodonts are rare or absent. Vertebrate faunas are poor in the earliest Devonian deposits, but become more common by the late Lochkovian, with near-shore assemblages characterized by Trundlelepis cervicostulata and ANostolepis@ guangxiensis, and deeper shelf assemblages by a new genus, possibly assignable to the Ischnacanthidae. The vertebrate record is sparse through the middle Pragian, though AN.@ guangxiensis is present low in the Coopers Creek Limestone (upper sulcatus-pireneae zones), being replaced by Nostolepoides platymarginata, Gomphonchus? bogongensis, and Radioporacanthodes sp. aff. R. (Gomphonchus) liujingensis by the kindlei Zone. Microvertebrate assemblages are more common by the late Pragian (pireneae Zone), with Radioporacanthodes sp. aff. R. liujingensis in deeper shelf deposits, and N. platymarginata and G.? bogongensis dominating near-shore assemblages. The earliest Emsian (dehiscens Zone) is marked by the incoming Cheiracanthoides wangi. Middle Emsian (perbonus-serotinus zones) assemblages are characterized by two new species, possibly assignable to Gomphonchus.The Middle Devonian cosmopolitan association of Cheiracanthoides comptus and AAcanthoides@ dublinensis, which characterizes early Middle Devonian faunas from North America, Europe and China, appears first in the latest Emsian at the serotinus-patulus zone boundary. As well as showing the value of acanthodians in biostratigraphy and as indicators of environmental settings, their use in biogeography was demonstrated. Although many of the acanthodian taxa are endemic, several are also found in other regions. The Silurian to earliest Devonian faunas of eastern Australia are most closely related to coeval Chinese assemblages. Several latest Silurian-earliest Devonian taxa are also recorded from the circum-Arctic region. The late Lochkovian to early Emsian assemblages, particularly from south-eastern Australia, have many taxa in common with Chinese faunas. The mid-Emsian taxa show highest endemicity; and the latest Emsian-Eifelian assemblages have the most cosmopolitan aspect. Acanthodian faunas become rarer and depauperate in the Middle Devonian, particularly in the south-eastern corner, and are mostly in poorly dated, ?fluviatile/marginal marine deposits. This study of acanthodian faunas has encompassed a full scale systematic review of the group in this region, an appraisal of phylogenetic relationships within the group and with other early vertebrates, their palaeoecology, and their use in biostratigraphy and biogeography.

nÃo hà / As peculiaridades de cada paÃs levam à utilizaÃÃo de mecanismos variados de alocaÃÃo de recursos hÃdricos, nÃo havendo uma regra geral para a resoluÃÃo do problema de escassez de Ãgua. O conhecimento dos modelos experimentados internacionalmente, com a identificaÃÃo de suas respectivas vantagens e desvantagens, sÃo de grande utilidade. O objetivo principal da gestÃo dos recursos hÃdricos à satisfazer a demanda, considerando as possibilidades e limitaÃÃes da oferta de Ãgua. Entretanto, para isso, à necessÃrio o conhecimento de todos os aspectos hidrolÃgicos, climatolÃgicos e fÃsicos da regiÃo para realizar um planejamento adequado de oferta hÃdrica, alÃm do conhecimento da populaÃÃo e dos mÃltiplos interesses, para um bom dimensionamento da demanda. Entretanto, quando o sistema hÃdrico à alimentado por influxos espacial e temporalmente variÃveis, que à o que ocorre em regiÃes semiÃridas, a escolha de um modelo eficaz de gestÃo dos recursos hÃdricos torna-se ainda mais complexa, devido Ãs incertezas presentes na avaliaÃÃo dos futuros nÃveis de Ãgua. Nestes casos, as incertezas tÃm um importante papel na gestÃo dos recursos hÃdricos. Em busca de um estudo mais profundo da gestÃo dos recursos hÃdricos nessas regiÃes de alta variabilidade climÃtica, foram tomados como anÃlise os modelos aplicados no Nordeste Brasileiro e na AustrÃlia. O presente trabalho apresenta a semelhanÃa nas caracterÃsticas do clima dessas regiÃes, a semelhanÃa nos problemas enfrentados por cada uma delas e, finalmente, traÃa um paralelo, atravÃs da anÃlise e comparaÃÃo dos diferentes mÃtodos de gestÃo dos recursos hÃdricos disponÃveis. / The peculiarities of each country lead to the use of various mechanisms of water allocation. There is no general rule for solving the problem of water scarcity. Understanding the models experienced internationally, identifying their respective advantages and disadvantages are very useful. The main objective of water management is to attend the demand, considering the possibilities and limitations of water supply. However, for this, it is necessary to know all hydrological, climatological and physical aspects of the region to conduct a proper planning of water supply, beyond the knowledge of the population and the multiple interests, to a good demand sizing. However, when the water system is supplied by spatial and temporal variability of inflows, as in semiarid regions, the choice of an effective model for water management becomes more complex, due to the uncertainties presented in evaluating future water levels. In these cases, uncertainties have an important role in water resources management. In the matter of a deep study of water resources management in these regions of high climate variability, models applied in Northeast Brazil and Australia were used as analysis. This paper presents the similarity of climate aspects, the similar problems faced by each region, and finally draws a parallel comparing different methods of available water management.

In rural inland, south-eastern Australia, allergy to the fungus Alternaria is prevalent and an important risk factor for asthma. The aim of the thesis was to investigate the distribution and factors influencing allergens of Alternaria in the air. As airborne allergenic spores were thought to arise from harvesting of nearby crops, two towns with different agricultural practices were studied. Moree has two crop harvesting periods in summer and autumn whilst Wagga Wagga has one harvesting period in summer. Over two years, air was sampled daily in Wagga Wagga and Moree using Burkard traps. The reliability of measurements from a single site to represent the distribution of airborne concentrations of spores across each town was examined using data from three traps simultaneously, sited 2.0 to 4.9 km apart, over four weeks. Substantial intra-class correlation coefficients (ICC) were observed between the three sampling sites across both towns (ICC=0.52, 95% CI 0.30-0.71 to 0.76, 95% CI 0.61-0.87) when counts of Alternaria spores were relatively high. The correlation was poor when counts were low. Of more than 365 trap tapes examined, the two microscopic traverses strongly correlated for counts of Alternaria spores (ICC=0.95, 95% CI 0.94-0.96). Alternaria was detected in both towns throughout the two year period with peaks in spore concentrations reflecting the season of crop harvesting in each region. Individual exposure to spores was examined. Thirty three subjects (adults and children from nine families) wore nasal air samplers and personal air samplers both inside and outside their homes. The effects of activity, location, age on the inhalation of Alternaria spores and variation between individuals in the same environment were determined. Every subject inhaled Alternaria spores. Personal exposure to Alternaria in the home environment varied substantially between subjects. Levels of fungal spores inhaled were higher during periods of activity than during rest, and higher while subjects were outdoors than indoors. During outdoor activity, the number of Alternaria spores inhaled ranged from 4 to 794 (median 11) spores/hr. Sources of airborne spores was investigated by sampling air above wheat and cotton crops near the towns during harvesting and non-harvesting periods, in a grain and cotton seed storage shed, and a cotton gin. Substantially higher concentrations were detected above crops during harvesting periods compared to non-harvesting periods. Peaks were associated with harvesting and other activities where plants were manipulated. By regression analysis spore concentrations in both towns were modelled against those detected above crops and with weather variables. Only one crop sampling period (cotton harvest) independently correlated with concentrations in town. Analysis combining all data showed concentrations of spores above crops correlated with spore concentrations in the town when lagged by one day. Variables of rainfall and maximum temperature influenced concentrations in both towns, and wind direction in Wagga Wagga alone. Parents of asthmatic children were asked by questionnaire in which locations symptoms were provoked. Asthma was reported to be exacerbated at grain farms and with disturbance of local vegetation in town and home gardens. Nasal sampling confirmed that activities that disturbed dust or vegetation increased the inhalation of spores. The factors that release allergen from spores were determined in a modified Halogen immunoassay. Approximately 60% of spores released allergen, and the proportion was influenced by isolate, nutrient availability, viability, and not influenced by sunlight or culture age up to 21 days. Germinating the spores significantly increased the proportion that released total allergen and Alt a 1 (p<0.0001). Alt a 1 appears to be a minor contributor to the total allergen released from spores except when spores have germinated. Conclusions: People living in inland rural regions of Australia are exposed to substantial quantities of allergenic spores of Alternaria. Exposure is a highly personal event and is largely determined by disturbance of local vegetation releasing spores such as from nearby crops by wind, harvesting, slashing, transport and processing of produce, and from within town and home gardens. Most spores inhaled are likely to be allergenic, with potency potentially increasing with viability.

In rural inland, south-eastern Australia, allergy to the fungus Alternaria is prevalent and an important risk factor for asthma. The aim of the thesis was to investigate the distribution and factors influencing allergens of Alternaria in the air. As airborne allergenic spores were thought to arise from harvesting of nearby crops, two towns with different agricultural practices were studied. Moree has two crop harvesting periods in summer and autumn whilst Wagga Wagga has one harvesting period in summer. Over two years, air was sampled daily in Wagga Wagga and Moree using Burkard traps. The reliability of measurements from a single site to represent the distribution of airborne concentrations of spores across each town was examined using data from three traps simultaneously, sited 2.0 to 4.9 km apart, over four weeks. Substantial intra-class correlation coefficients (ICC) were observed between the three sampling sites across both towns (ICC=0.52, 95% CI 0.30-0.71 to 0.76, 95% CI 0.61-0.87) when counts of Alternaria spores were relatively high. The correlation was poor when counts were low. Of more than 365 trap tapes examined, the two microscopic traverses strongly correlated for counts of Alternaria spores (ICC=0.95, 95% CI 0.94-0.96). Alternaria was detected in both towns throughout the two year period with peaks in spore concentrations reflecting the season of crop harvesting in each region. Individual exposure to spores was examined. Thirty three subjects (adults and children from nine families) wore nasal air samplers and personal air samplers both inside and outside their homes. The effects of activity, location, age on the inhalation of Alternaria spores and variation between individuals in the same environment were determined. Every subject inhaled Alternaria spores. Personal exposure to Alternaria in the home environment varied substantially between subjects. Levels of fungal spores inhaled were higher during periods of activity than during rest, and higher while subjects were outdoors than indoors. During outdoor activity, the number of Alternaria spores inhaled ranged from 4 to 794 (median 11) spores/hr. Sources of airborne spores was investigated by sampling air above wheat and cotton crops near the towns during harvesting and non-harvesting periods, in a grain and cotton seed storage shed, and a cotton gin. Substantially higher concentrations were detected above crops during harvesting periods compared to non-harvesting periods. Peaks were associated with harvesting and other activities where plants were manipulated. By regression analysis spore concentrations in both towns were modelled against those detected above crops and with weather variables. Only one crop sampling period (cotton harvest) independently correlated with concentrations in town. Analysis combining all data showed concentrations of spores above crops correlated with spore concentrations in the town when lagged by one day. Variables of rainfall and maximum temperature influenced concentrations in both towns, and wind direction in Wagga Wagga alone. Parents of asthmatic children were asked by questionnaire in which locations symptoms were provoked. Asthma was reported to be exacerbated at grain farms and with disturbance of local vegetation in town and home gardens. Nasal sampling confirmed that activities that disturbed dust or vegetation increased the inhalation of spores. The factors that release allergen from spores were determined in a modified Halogen immunoassay. Approximately 60% of spores released allergen, and the proportion was influenced by isolate, nutrient availability, viability, and not influenced by sunlight or culture age up to 21 days. Germinating the spores significantly increased the proportion that released total allergen and Alt a 1 (p<0.0001). Alt a 1 appears to be a minor contributor to the total allergen released from spores except when spores have germinated. Conclusions: People living in inland rural regions of Australia are exposed to substantial quantities of allergenic spores of Alternaria. Exposure is a highly personal event and is largely determined by disturbance of local vegetation releasing spores such as from nearby crops by wind, harvesting, slashing, transport and processing of produce, and from within town and home gardens. Most spores inhaled are likely to be allergenic, with potency potentially increasing with viability.

In 2025, there will be almost 8 billion people to feed as the worlds population rapidly increases. To meet domestic and export demands, Australian grain productivity needs to approximately triple in the next 20 years, and this production needs to occur in an environmentally sustainable manner. The advent of Hi-tech Precision Farming in Australia has shown promise in recent time to optimize the use of resources. Most

The task of producing policies for the management of Earth’s natural resources is a problem of the gravest concern worldwide. Such policies must address both responsible use in the present and the sustainability of those finite resources in the future. Resources are showing the adverse results of generations of exploitation, and communities fail to see the outcomes of past policies that have produced, and continue to produce, these results. They have not learned from past policy failures, and consequently fail to produce natural resource management (NRM) policies that support sustainable development.¶ It will be argued that NRM policy makers fail to learn from the past because they do not have a good historical perspective and a clear understanding of the dynamics of the complex human-environment system that they manage. It will also be argued that historians have not shown an interest in collaborating with policy makers on these issues, even though they have much to offer. Therefore, a new approach is proposed, which brings the skills and understanding of the trained historian directly into the policy arena.¶ This approach is called Applied Environmental History (AEH). Its aims are to help establish an area of common conceptual ground between NRM practitioners, policy makers, historians and dynamicists; to provide a framework that can help NRM practitioners and policy makers to take account of the historical and dynamical issues that characterise human-environment relationships; and to help NRM practitioners and policy makers improve their capacity to learn from the past. Applied Environmental History captures the characteristics of public and applied history and environmental history. In order to include an understanding of feedback dynamics in human-environment systems, it draws on concepts from dynamical systems theory. Because learning from the past is a particular form of learning from experience, AEH also draws on theories of cognitive adaptation.¶ Principles for the application of AEH are developed and then tested in an exploratory study of irrigation development that is focused on the NRM issue of salinity. Since irrigation salinity has existed for centuries, and is a serious environmental problem in many parts of the world, it is a suitable NRM context in which to explore policy makers' failure to learn from the past. AEH principles guide this study, and are used, together with insights generated from the study, as the basis for the design of AEH Guidelines.