Biology subjects

Rooke, D.

Publications and source records attributed to Rooke, D..

3 recordsLinked to original sources

bioRxiv2025

Comparative analysis of morphological and acoustic correlates of bush-cricket tympanic membranes

Bush-crickets exhibit remarkable auditory diversity, having the ears in the forelegs, where the tympana could be exposed or covered by cuticular flaps known as auditory pinnae. These tympanic membranes receive sound either directly or internally via an acoustic tracheal tube. Despite extensive research on auditory tuning, the relationships between tympanal structure, body size, and acoustic traits remain unclear. In this study, {micro}CT reconstructions with AI-assisted segmentation and phylogenetically informed regressions across 18 bush-cricket species were used to investigate how tympanal surface area and mean cross-sectional thickness relate to body size, carrier frequency, and the presence of auditory pinnae. Tympanal surface area scaled positively with body size, whereas thickness was independent of size. Carrier frequency decreased with increasing body size but showed no direct association with tympanal properties. Among 14 species with auditory pinnae, tympanal dimensions showed no correlation with peak cavity resonance frequency, indicating semi-independent evolution of pinna cavity and tympanal traits. Across species, pinnae did not alter tympanal surface area, although unilateral pinnae were linked to thicker tympana. Within these unilateral species, the pinna-covered tympanum remained consistently larger in area but thinner than the exposed side. Overall, these findings indicate that tympanal evolution reflects a balance of scaling constraints and localised effects of auditory pinnae. Summary StatementThe tympanal morphology in bush-crickets reflects a balance of scaling and pinna effects. Surface area scales with body size and unilateral pinnae generate consistent asymmetries.

biophysics↗

bioRxiv2022

The faecal microbiome of the wild European badger Meles meles; a comparison against other wild omnivorous mammals from across the globe

Here we investigate the faecal microbiome of wild European badgers Meles meles using samples collected at post-mortem as part of the All Wales Badger Found Dead study based on sequencing the V3-V4 region of the 16S rRNA gene. This is the first published characterisation of the badger microbiome. We initially undertook a sex-matched age comparison between the adult and cub microbiomes. Analysis used the QIIME 2 pipeline utilising DADA2 and the Silva database for taxonomy assignment. Fusobacteria appeared to be more abundant in the microbiomes of the cubs than the adults although no significant difference was seen in alpha or beta diversity between the adult and cub badger microbiomes. Comparisons were also made against other wild, omnivorous, mammals faecal microbiomes using publicly available data. Significant differences were seen in both alpha and beta diversity between the microbiomes from different species. As a wildlife species of interest to the disease bovine tuberculosis, knowledge of the faecal microbiome could assist in identification of infected badgers. Our work here suggests that if comparisons were made between the faeces of bTB infected and non-infected badgers, its possible age may not have a significant impact on the microbiome.

microbiology↗

bioRxiv2021

The Application of Countercurrent Chromatography for the study of Bacteriophages

1.Bacteriophages (phages) are viruses that target bacteria, with the ability to lyse and kill host bacterial cells. Due to this, they have been of some interest as a therapeutic since their discovery in the early 1900s, but with the recent increase in antibiotic resistance, phages have seen a resurgence in attention. Current methods of isolation and purification of phages can be long and tedious, with caesium chloride concentration gradients the gold standard for purifying a phage fraction. Isolation of novel phages requires centrifugation and ultrafiltration of mixed samples, such as water sources, effluent or faecal samples etc, to prepare phage filtrates for further testing. We propose countercurrent chromatography as a novel and alternative approach to use when studying phages, as a scalable and high-yield method for obtaining phage fractions. However, the full extent of the usefulness and resolution of separation with this technique has not been researched; it requires optimisation and ample testing before this can be revealed. Here we present an initial study to determine survivability of two phages, T4 and {phi}X174, using only water as a mobile phase in a Spectrum Series 20 HPCCC. Both phages were found to remain active once eluted from the column. Phages do not fully elute from the column and sodium hydroxide is necessary to flush the column between runs to deactivate remaining phages.

microbiology↗