This retrospective cohort study of 336 lateral cephalometric radiographs from 62 children (34 males and 28 females) with non-syndromic complete unilateral cleft lip and palate from the Hospital for Sick Children and 50 non-cleft children (25 females and 25 males) from the Burlington Growth Centre. Cervical vertebral maturation stages at age 10, 12 and 14 were determined. The cervical vertebral maturation (CVM) was established using the 6-stage method described by Baccetti and coworkers. The reproducibility of classifying CVM stages was high, with an inter-rater reliability (ICC) with the standard (Baccetti et al, 2005) of 80% and intra-rater reliability of 85%. The Cervical vertebral maturation stage for both males and females with UCLP was significantly later than children without a cleft at age 10, 12 and 14. The results suggest that patients with UCLP show delayed skeletal maturation in comparison to non-cleft patients.

Mobility of the vertebral column is important for many ecological aspects of vertebrates, especially in the cervical series, which connects the head to the main body. Thus, fusion within the cervical series is hypothesized to have ecological and behavioural implications. Fused, anterior cervical vertebrae have evolved independently over 20 times in ecologically disparate amniotes, most commonly in pelagic, ricochetal, and fossorial taxa, suggesting an adaptive function for the ‘syncervical.’ Fusion may help increase out-force during head-lift digging or prevent anteroposteriorly shortened vertebrae from mechanically failing during locomotion, but no hypothesis for syncervical function has been tested. The syncervical of neoceratopsian dinosaurs is hypothesized to support large heads or aid in intraspecific combat. Tests of correlated character evolution within a ceratopsian phylogeny falsify these hypotheses, as the syncervical evolves before large heads and cranial weaponry. Alternative functional hypotheses may involve ancestral burrowing behaviour or unique feeding ecology in early neoceratopsians.

Mobility of the vertebral column is important for many ecological aspects of vertebrates, especially in the cervical series, which connects the head to the main body. Thus, fusion within the cervical series is hypothesized to have ecological and behavioural implications. Fused, anterior cervical vertebrae have evolved independently over 20 times in ecologically disparate amniotes, most commonly in pelagic, ricochetal, and fossorial taxa, suggesting an adaptive function for the ‘syncervical.’ Fusion may help increase out-force during head-lift digging or prevent anteroposteriorly shortened vertebrae from mechanically failing during locomotion, but no hypothesis for syncervical function has been tested. The syncervical of neoceratopsian dinosaurs is hypothesized to support large heads or aid in intraspecific combat. Tests of correlated character evolution within a ceratopsian phylogeny falsify these hypotheses, as the syncervical evolves before large heads and cranial weaponry. Alternative functional hypotheses may involve ancestral burrowing behaviour or unique feeding ecology in early neoceratopsians.

Vertebral development patterns have been well characterised in the Paleozoic "lepospondyls" and "labyrinthodonts", as well as in modern amniotes, frogs and caecilians. Each of those groups consistently develop either the neural arches before the centra or the centra before neural arches. Preliminary studies confirmed that members of the Urodela exhibit both developmental patterns. To understand if there is any consistency in patterns of vertebral development within and between families, as well as to investigate the distribution of patterns within the order, 120 salamander larvae from the ten living salamander families were cleared, stained and examined for osteological development. In order to provide a basis of comparison between different developmental stages observed in different families, a staging table was constructed. The complete osteological development of every cleared and stained specimen used in this study was then described. Finally, the general pattern of vertebral development was examined and characteristic patterns for each family were mapped on an accepted phylogeny of salamander relationships.

Thesis (PhD)--University of South Australia, 2002.

Thesis (MAppSc in Physiotherapy) -- University of South Australia, 1993

Thesis (MPhysio)--University of South Australia, 1998

Thesis (MAppSc) -- University of South Australia, 1998

Research Doctorate - Doctor of Philosophy (PhD) / World shark populations are declining rapidly from the increased demand for shark meat and fins and from their capture as by-catch. Techniques to accurately and reliably estimate the age of elasmobranchs are required to understand life history and develop management strategies. Although some biological information exists for the harvested species, few of the many shark species caught as by-catch have been investigated. In the waters of New South Wales, Australia, the Port Jackson shark (Heterodontus portusjacksoni) is a non-targeted species, however it is a major contributor to the elasmobranch by-catch in the bottom trawl and prawn fisheries. Although some biological and ecological information exists on Port Jackson sharks from New South Wales, there is no understanding of suitable techniques to age this species and of the age structure of the New South Wales’ population. Hence, the main purpose for the present study was to determine a suitable technique to age Port Jackson sharks and thereby provide essential age and growth data for its future management, sustainable use and conservation. This study consisted of research into: (1) the macroscopic anatomy of the vertebral centra and dorsal spines from 652 H. portusjacksoni to explore their suitability as ageing structures; (2) a comparison of whole and sectioned vertebral centra and of whole and sectioned dorsal spines for ageing; (3) validation of the annual formation of growth bands; (4) a comparison of the effect of prior experience on readers’ ability to count annual growth bands in vertebral centra; and (5) the development of age-growth models for the New South Wales’ population of H. portusjacksoni. Two types of vertebral centra (trunk and caudal vertebrae) were found in the vertebral column. Both vertebrae consisted of a centrum, 2 ribs, 4 neural arches, basiopophyses and neural foramen and decreased in size from anterior to posterior. A strong linear relationship was identified between vertebral diameter (VD) and fork length (FL). Each dorsal spine was positioned anterior to the dorsal fin and consisted of a stem and the cap. A strong linear relationships were identified between spine base width (SBW) and FL. The existence of alternating opaque and translucent band pairs in both structures further suggested they may be suitable for ageing purposes. Validation (calcein and oxytetracycline injections, marginal increment analysis, and centrum edge analysis) confirmed that translucent band pairs were formed during the winter (September-November) and were annual in both vertebral centra and dorsal spines. Whole and sectioned vertebral centra and dorsal spines were individually examined to determine which method best estimated the age. Although both methods had individual low reading bias and high precision, there was a difference between the two methods. The average bias between the two methods using vertebral centra was -0.158 ±0.05 and the coefficient of variance (CV) was 92.32% for females and -0.157 ±0.03 and CV was 56.95% for males. This indicated that sectioned vertebral centra returned higher ages than whole vertebral centra. When comparing whole dorsal spine age estimates to sectioned dorsal spines, there was an average bias between methods of -0.22 ±0.026 and a low precision 73.09%. Again indicating that sectioned dorsal spines returned higher ages than whole dorsal spines. A comparison of ages estimated from sectioned vertebral centra and sectioned dorsal spines showed that vertebral centra aged older than dorsal spines. Although the two structures each had low reading bias and high reading precision, there were differences between the two structures. The average bias between the two structures was -0.4 ±0.03 and the CV was low (74.7%), indicating that there was a significant difference in age derived from the two structures. Therefore, great caution should be taken when choosing which structure to use for age estimation. Ages of sharks estimated from the recommended sectioned vertebral centra ranged from 0.2 to 32.5 years for females and 0.2 to 23.8 years for males. Four different growth models were compared using both sectioned vertebral centra and sectioned dorsal spines to estimate the best suitable growth curve. Out of the 4 growth models the Gompertz Growth Function (GGF) best described the growth of H. portusjacksoni. von Bertalanffy growth parameters estimated from ageing data using the GGF for females were t0 = 2.584 yr, k = 0.111, L∞ = 1134.1 mm FL, and for males t0 = 1.629 yr, k = 0.131, L∞ = 1012.9 mm FL. This indicates that H. portusjacksoni has a slow growth rate and a longer life span than most other elasmobranch species. The effect of reader’s experience on the bias and precision of age estimates of sectioned vertebral centra was determined in an experiment that compared the author (an experienced vertebral centra reader) with an experienced fish otolith reader, two readers recently trained in reading vertebral centra (but lacking experience), and two untrained and inexperienced readers. Bias and precision were determined for each reader from two ageing trials with the same structure three months apart. Between-trials bias for each reader (except the author)ranged from 0.033 to 0.13 and precision ranged from 8.2 to 19.5%, while the author had low bias 0.006 and high precision 1.1%. When comparing all the readers with the author, bias ranged from 0.033 to 0.13 with an 8.2 to 19.5% precision for trial one, and 0.017 to 0.5 with precision between 2.5 to 5.4% in trial two. The age-bias plots comparing the two trials all indicated that only the author was consistent. And the age-bias plots between the author and the other readers all indicated that neither experience in ageing teleost otoliths or limited training in ageing enhanced the bias or precision compared to inexperienced elasmobranch agers.

Research Doctorate - Doctor of Philosophy (PhD) / World shark populations are declining rapidly from the increased demand for shark meat and fins and from their capture as by-catch. Techniques to accurately and reliably estimate the age of elasmobranchs are required to understand life history and develop management strategies. Although some biological information exists for the harvested species, few of the many shark species caught as by-catch have been investigated. In the waters of New South Wales, Australia, the Port Jackson shark (Heterodontus portusjacksoni) is a non-targeted species, however it is a major contributor to the elasmobranch by-catch in the bottom trawl and prawn fisheries. Although some biological and ecological information exists on Port Jackson sharks from New South Wales, there is no understanding of suitable techniques to age this species and of the age structure of the New South Wales’ population. Hence, the main purpose for the present study was to determine a suitable technique to age Port Jackson sharks and thereby provide essential age and growth data for its future management, sustainable use and conservation. This study consisted of research into: (1) the macroscopic anatomy of the vertebral centra and dorsal spines from 652 H. portusjacksoni to explore their suitability as ageing structures; (2) a comparison of whole and sectioned vertebral centra and of whole and sectioned dorsal spines for ageing; (3) validation of the annual formation of growth bands; (4) a comparison of the effect of prior experience on readers’ ability to count annual growth bands in vertebral centra; and (5) the development of age-growth models for the New South Wales’ population of H. portusjacksoni. Two types of vertebral centra (trunk and caudal vertebrae) were found in the vertebral column. Both vertebrae consisted of a centrum, 2 ribs, 4 neural arches, basiopophyses and neural foramen and decreased in size from anterior to posterior. A strong linear relationship was identified between vertebral diameter (VD) and fork length (FL). Each dorsal spine was positioned anterior to the dorsal fin and consisted of a stem and the cap. A strong linear relationships were identified between spine base width (SBW) and FL. The existence of alternating opaque and translucent band pairs in both structures further suggested they may be suitable for ageing purposes. Validation (calcein and oxytetracycline injections, marginal increment analysis, and centrum edge analysis) confirmed that translucent band pairs were formed during the winter (September-November) and were annual in both vertebral centra and dorsal spines. Whole and sectioned vertebral centra and dorsal spines were individually examined to determine which method best estimated the age. Although both methods had individual low reading bias and high precision, there was a difference between the two methods. The average bias between the two methods using vertebral centra was -0.158 ±0.05 and the coefficient of variance (CV) was 92.32% for females and -0.157 ±0.03 and CV was 56.95% for males. This indicated that sectioned vertebral centra returned higher ages than whole vertebral centra. When comparing whole dorsal spine age estimates to sectioned dorsal spines, there was an average bias between methods of -0.22 ±0.026 and a low precision 73.09%. Again indicating that sectioned dorsal spines returned higher ages than whole dorsal spines. A comparison of ages estimated from sectioned vertebral centra and sectioned dorsal spines showed that vertebral centra aged older than dorsal spines. Although the two structures each had low reading bias and high reading precision, there were differences between the two structures. The average bias between the two structures was -0.4 ±0.03 and the CV was low (74.7%), indicating that there was a significant difference in age derived from the two structures. Therefore, great caution should be taken when choosing which structure to use for age estimation. Ages of sharks estimated from the recommended sectioned vertebral centra ranged from 0.2 to 32.5 years for females and 0.2 to 23.8 years for males. Four different growth models were compared using both sectioned vertebral centra and sectioned dorsal spines to estimate the best suitable growth curve. Out of the 4 growth models the Gompertz Growth Function (GGF) best described the growth of H. portusjacksoni. von Bertalanffy growth parameters estimated from ageing data using the GGF for females were t0 = 2.584 yr, k = 0.111, L∞ = 1134.1 mm FL, and for males t0 = 1.629 yr, k = 0.131, L∞ = 1012.9 mm FL. This indicates that H. portusjacksoni has a slow growth rate and a longer life span than most other elasmobranch species. The effect of reader’s experience on the bias and precision of age estimates of sectioned vertebral centra was determined in an experiment that compared the author (an experienced vertebral centra reader) with an experienced fish otolith reader, two readers recently trained in reading vertebral centra (but lacking experience), and two untrained and inexperienced readers. Bias and precision were determined for each reader from two ageing trials with the same structure three months apart. Between-trials bias for each reader (except the author)ranged from 0.033 to 0.13 and precision ranged from 8.2 to 19.5%, while the author had low bias 0.006 and high precision 1.1%. When comparing all the readers with the author, bias ranged from 0.033 to 0.13 with an 8.2 to 19.5% precision for trial one, and 0.017 to 0.5 with precision between 2.5 to 5.4% in trial two. The age-bias plots comparing the two trials all indicated that only the author was consistent. And the age-bias plots between the author and the other readers all indicated that neither experience in ageing teleost otoliths or limited training in ageing enhanced the bias or precision compared to inexperienced elasmobranch agers.