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Identifying mechanisms that drive population divergence under varying geographic and ecological scenarios can inform our understanding of evolution and speciation. In particular, analysis of genetic data from island populations with known colonisation timelines allows us to identify potential source populations of diverging island subspecies and current relationships among populations. Silvereyes (Zosterops lateralis) are a small passerine that have served as a valuable study system to investigate evolutionary patterns on both large and small geographic scales. We examined genetic relatedness and diversity of two silvereye subspecies, the mainland Z. l. cornwalli and island Z. l. chlorocephalus, and used 18 077 single nucleotide polymorphisms (SNPs), to compare locations across southeast Queensland, Australia. Although silvereyes are prolific island colonisers our findings revealed population divergence over relatively small spatial scales was strongly influenced by geographic isolation mediated by water barriers. Strong genetic connectivity was displayed between mainland sites, but minimal inter-island connectivity was shown despite comparable sampling distances. Genetic diversity analysis showed little difference in heterozygosity between island and mainland populations, but lower inbreeding scores among the island populations. Our study confirmed the range of the Z. l. chlorocephalus subspecies throughout the southern Great Barrier Reef. Our results show that water barriers and not geographic distance per se are important in driving incipient divergence in island populations. This helps to explain the relatively high number of phenotypically differentiated, but often geographically proximate, island silvereye subspecies compared to a lower number of phenotypically less well-defined Australian continental subspecies. [ABSTRACT FROM AUTHOR]

The Great Barrier Reef Marine Park was established to provide for conservation and ecologically sustainable multiple use of 344,400 km of a large marine ecosystem. Management is based on multiple use, with zoning as a fundamental component of marine spatial planning. The legislative framework, including a specific Act and Regulations, address the objectives of ecosystem-based, integrated management of human uses and impacts consistent with best contemporary understanding of biological diversity. Zoning is one of a suite of management tools that include other spatial and temporal management tools and non-spatial measures including public education, community engagement, codes of environmental best practice, industry partnerships and economic instruments. The first section of the Great Barrier Reef Marine Park came into operation in 1981 and the most recent zoning came into operation in mid 2004. The paper discusses some common misunderstandings about zoning and identifies lessons that appear relevant for others addressing management and use of marine ecosystems and natural resources. [ABSTRACT FROM AUTHOR]

Evidence shows that in the modern ocean, coral reefs are disappearing, and these losses are tied to climate change. However, research also shows that coral reefs can adapt rapidly to changing conditions leading some researchers to suggest that some reef systems will survive future climate change through adaptation. It is known that there were changes in the area covered by coral reefs in the past. Therefore, it is important to investigate the long-term response of coral reefs to environmental changes and high sea-surface temperatures (SSTs). However, because of diagenetic issues with SST proxies in neritic, metastable carbonate-rich environments, there is an incomplete and sometimes even incorrect understanding of how changes in SSTs affect carbonate reef systems. A good example is the Queensland Plateau offshore northeast Australia next to the threatened Great Barrier Reef. In the Late Miocene, between 11 and 7 Ma, a partial drowning caused the reef area on the Queensland Plateau to decline by ~ 50% leading to a Late Miocene change in platform geometry from a reef rimmed platform to a carbonate ramp. This reef decline was interpreted to be the result of SSTs at the lower limit of the modern reef growth window (20–18 °C). This article presents a new Late Miocene—ased SST record from the Coral Sea based on the TEX86H molecular paleothermometer, challenging this long held view. Our new record indicates warm tropical SSTs (27–32 °C) at the upper end of the modern reef growth window. We suggest that the observed temperatures potentially exceeded the optimal calcification temperatures of corals. In combination with a low aragonite supersaturation in the ocean, this could have reduced coral growth rates and ultimately lowered the aggradation potential of the reef system. These sub-optimal growth rates could have made the coral reefs more susceptible to other stressors, such as relative sea-level rise and/or changes in currents leading to reef drowning. Given that these changes affected coral reefs that were likely adapted to high temperature/low aragonite saturation conditions suggests that reefs that have adapted to non-ideal conditions may still be susceptible to future climate changes due to the interaction of multiple stressors associated with climate change. [ABSTRACT FROM AUTHOR]

We have characterised the northern Pacific undescribed sponge Haliclona (? gellius) sp. based on rDNA of the sponge and its associated microorganisms. The sponge is closely related to Amphimedon queenslandica from the Great Barrier Reef as the near-complete 18S rDNA sequences of both sponges were identical. The microbial fingerprint of three specimens harvested at different times and of a transplanted specimen was compared to identify stably associated microorganisms. Most bacterial phyla were detected in each sample, but only a few bacterial species were determined to be stably associated with the sponge. A sponge-specific β- and γ-Proteobacterium were abundant clones and both of them were present in three of the four specimens analysed. In addition, a Planctomycete and a Crenarchaea were detected in all sponge individuals. Both were closely related to operational taxonomic units that have been found in other sponges, but not exclusively in sponges. Interestingly, also a number of clones that are closely related to intracellular symbionts from insects and amoeba were detected. [ABSTRACT FROM AUTHOR]

Focuses on the microbial symbionts of the sponge Candidaspongia flabellata found in the Australian Great Barrier Reef, Queensland. Diversity of the microbial community associated with the sponge; Use of 16S ribosomal RNA gene sequencing of the microbial symbionts for phylogenetic characterization; Presence of various morphotypes of bacteria on C. flabellata.