http://hdl.handle.net/10453/37630 2026-10-15T03:48:11Z http://hdl.handle.net/10453/197078 Title: Estimating global bee species richness and taxonomic gaps. Authors: Dorey, JB; Gilpin, A-M; Johnston, NP; Esquerré, D; Hughes, AC; Ascher, JS; Orr, MC Abstract: Robust species richness estimates are critical for meaningful conservation prioritisation, understanding ecosystem resilience, and studying evolutionary processes. Yet, they remain elusive even for some of the best-studied groups and regions. As keystone pollinators, bees are crucial for the maintenance of healthy ecosystems, yet rigorous estimates of their species richness are lacking. Here, we statistically estimate global, continental, and country lower bounds of bee species richness. Globally, we estimate 24,705-26,164 bee species, an 18-25% increase, representing at least 32-45 years of taxonomic research. We estimate particularly high undescribed biodiversity from Asia, Africa, and the Americas. We find that taxonomic gaps are correlated with gross domestic product per capita (GDPc), observed species richness, number of occurrence records, and completeness of occurrence databases. Our statistical R-package framework will progress our understanding of lesser-known groups, downstream consensus, and mobilise existing occurrence datasets to quantitatively estimate species richness on global scales. 2026-02-24T00:00:00Z http://hdl.handle.net/10453/196875 Title: Assessing the Distribution, Density and Ecological Impacts of Feral Deer in Urban and Peri-Urban Areas of Lake Macquarie, New South Wales, Australia Authors: Vuong, L; Krix, DW; Martin, LJ Abstract: Feral deer are associated with a range of environmental impacts including overgrazing and trampling of native vegetation, increased insolation, ringbarking, creation of wallows, erosion and stream degradation. Consequences of invasive deer impacts can threaten vulnerable ecological communities and have the potential to alter long-term vegetation dynamics if deer populations are left uncontrolled. Studies of feral deer impacts in Australia to date have mostly focused on forested natural areas and agricultural lands; however, deer also pose a threat to the environment and property in urban and peri-urban areas. In this study we investigated the impacts of feral deer (fallow and possibly red deer) in urban and peri-urban habitats using faecal pellet counts and vegetation browsing assessments at 29 sites throughout western Lake Macquarie. Deer were found to have a patchy distribution; however, where present, significant impacts were observed. Browsing impacts were significantly greater in plots containing faecal pellets. There was a significant relationship between the number of faecal pellets detected and browsing intensity. Forested wetland had the highest browse rate of all vegetation types at 35%, with dry sclerophyll at 10% and wet sclerophyll at 20%. This study provides insights into the study of feral deer impacts in urban and peri-urban areas. We provide recommendations for researchers conducting future studies in such habitats to quantify ecological impacts and to overcome access difficulties experienced in this study. 2026-09-01T00:00:00Z http://hdl.handle.net/10453/196818 Title: Molecular characterization of covRS mutations in M1UK Streptococcus pyogenes. Authors: Pritchard, J; Proctor, E-J; Wang, J; Johnston, NP; Hayes, A; McCorkell, G; Yu, H; Tree, J; Davies, MR; Walker, MJ; Sluyter, R; Brouwer, S; Sanderson-Smith, ML Abstract: Increasingly invasive Streptococcus pyogenes disease has been linked to the emergence of the M1UK lineage. Here, we used a murine infection model to investigate the ability of M1UK to accumulate mutations in the covRS operon which regulates up to 15% of the genome, including multiple virulence factors. Assessing an M1UK isolate carrying an Ala111Val nonsynonymous mutation showed that in vitro, M1UK CovRAla111Val was characterized by decreased SpeB expression, increased streptolysin O and hyaluronic acid capsule expression, and resistance to neutrophil killing. While Ala111Val represents a minor biochemical change, we show that CovRAla111Val prevents phosphorylation-dependent dimerization. Specifically, molecular dynamics simulations suggest CovRAla111Val destabilizes the interface between CovR monomers that facilitate dimerization, likely inhibiting CovR dimer-mediated transcriptional repression and promoting altered virulence factor expression. Ultimately, this work underscores the need for ongoing epidemiological surveillance to monitor the emergence of such mutations within the already hypervirulent M1UK lineage. 2026-06-04T00:00:00Z http://hdl.handle.net/10453/196745 Title: A New Conditional Transcription Factor for Use in Toxoplasma Gondii. Authors: Sharifpour, MF; Khadiv, S; Uboldi, AD; Jayawickrama, AA; Manning, S; Whittall, J; Bottema, CDK; Ellis, JT; Howe, DK; Wilson, DW; Hemmatzadeh, F; Tonkin, CJ; McAllister, MM Abstract: Toxoplasma gondii is an intracellular eukaryotic parasite in the phylum Apicomplexa. Reversible, conditional control of gene transcription was achieved previously in this organism using a tet-off system that was controlled by tetracycline. Although revolutionary for the field at the time, that system in Toxoplasma yielded modest signal-to-noise ratios (SNR) and proved to be leaky in the "off" state (i.e., it suffered from high background expression). Here we report the development of a new reversible and robust Conditional Transcription Factor (CTF) that is controlled by rapamycin. Although we originally intended to design a dimerizable drug-on transcription control system, the CTF unexpectedly functions in a drug-off fashion. In stably-transfected tachyzoites, CTF regulates a fluorescent reporter gene in Toxoplasma to achieve almost no background expression in the presence of rapamycin (i.e. near-zero leakiness), while in the absence of rapamycin 84% of tachyzoites express EYFP in comparison with 87% of constitutively-expressed positive controls, with 59% mean fluorescence intensity relative to positive controls. Conditional regulation of the median fluorescence intensity of the reporter gene reached an impressive SNR averaging 1489, approximating an "on/off" switch. The modular design of the CTF is expected to facilitate application to varied genes, incremental modifications, and adaptation for use in other apicomplexan organisms. 2026-05-01T00:00:00Z