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For many people, fruit flies are simply an annoyance. However, as they perform their persistent straight-line flights, followed by quick switches in direction, they display a remarkable ability in both vision and agility. A key part of the fruit fly visual system that ensures that this behaviour occurs is the ability to stabilise locomotion within the world given perturbation, this is the optomotor response. Recent studies have introduced the existence of anti-optomotor behaviour in Drosophila. Under certain conditions, flies show a consistent, large, and sustained response in the opposite direction to rotational optic flow. However, the underlying reasons for this behaviour remain unclear. We aimed to investigate the features and reasons for the anti-optomotor response. In addition we aimed to investigate the ability of flies to use active sensing mechanisms to allow for greater visual motion perception. Our findings reveal that flies perceive rotational optic flow normally during anti-optomotor behaviour. However, they exhibit significant visual nystagmus of the head, which coincides with the occurrence of anti-optomotor behaviour. Moreover, this behavior is linked to high-frequency locomotory activity, and looming stimuli that increase the likelihood of directional changes also amplify the occurrence of anti-optomotor behaviour. Interestingly, restraining head movements does not eliminate the anti-optomotor response, although it does impair overall turning ability at lower stimulus wavelengths. Furthermore, our study reveals that fruit flies possess better visual acuity than previously believed, as they respond to 2° wavelength gratings, well below the 4-5° Nyquist limit. Notably, this behaviour is observable exclusively through head-optomotor responses, emphasizing the significance of active sensing mechanisms in fly vision. The characteristics of anti-optomotor behaviour suggest that a saccadic-like behavioural pattern resembling course-changing movements is the fundamental cause of this phenomenon, although the exact neural circuitry involved is still unknown. Additionally, the presence of hyperacute behavioural responses lends support to the microsaccadic sampling hypothesis of animal vision and furthermore explains previous contradictory findings in regards to this phenomenon.

1,2-Diols and 1,2-ketoalcohols are important functional groups that can require multiple steps to synthesise, which increases yield losses, waste and often uses stoichiometric reagents and toxic/expensive catalysts. The ability to transform simple substrates into more complex products in one-pot with two or more catalysed steps is desirable, especially if a single catalyst can carry out both reactions. A multifunctional catalyst system was designed to transform primary alcohols into 1,2-diols through three sequential catalysed transformations; transfer dehydrogenation, benzoin condensation, and transfer hydrogenation. Two families of novel ligands and iridium(III) complexes bearing either thiazole or triazole rings were synthesised towards creating a multifunctional catalyst and characterised using mass spectrometry, NMR spectroscopy and x-ray crystallography. During the synthesis of the ligands, the alkylation of thiazole compounds and the DIBAL-H reduction of a thiazole ester were developed. The organo-organometallic complexes were tested for the transfer dehydrogenation of benzyl alcohol and the reaction was investigated to show that the equilibrium between the forward and reverse reaction, and not catalyst deactivation, was the cause of limited conversion. The hydrogen acceptor was varied and acetone was found to be the most effective when used as a dilute solvent with strictly inert reaction conditions, reaching up to 78% conversion. Four of the novel complexes gave comparable conversions to the control catalyst; however, the benzoin condensation reaction was not successful. The transfer hydrogenation of benzaldehyde was tested and found give quantitative conversions with the majority of novel complexes. A substrate scope identified that the more electron rich substrates were more easily oxidised. With a secondary alcohol, the transfer dehydrogenations occurred at a faster rate compared to the primary alcohol, reaching quantitative conversion.