The evolution of dim light vision in vertebrates. High sensitivity (rod-based) vision has been extremely important for the survival and adaptive radiation of many vertebrates, including humans over evolutionary time. This multidisciplinary project will reveal the evolutionary and physiological constraints on early photoreception and the difficulties in operating over an enormous range of lighting conditions. Not only will the findings be crucial for our understanding of basic mechanisms of dim l ....The evolution of dim light vision in vertebrates. High sensitivity (rod-based) vision has been extremely important for the survival and adaptive radiation of many vertebrates, including humans over evolutionary time. This multidisciplinary project will reveal the evolutionary and physiological constraints on early photoreception and the difficulties in operating over an enormous range of lighting conditions. Not only will the findings be crucial for our understanding of basic mechanisms of dim light vision, but also provide potential insights into the physiological bases of various rod dystrophies affecting humans and the improved design of more sensitive cameras and safe light environments for rearing animals in captivity e.g. for aquaculture.Read moreRead less
A contractile cochlear frame - a possible new mechanism of sound adaptation. It is generally accepted that the rigid frame that harbours sensory structures in the hearing organs of modern higher vertebrates has only a passive supporting role. We have discovered a contractile component in the cartilaginous cochlear frame of the lizard Teratoscincus scincus and demonstrated that the tonus of the contractile tissue can be regulated. We hypothesize a new, previously unknown mechanism of slow mechani ....A contractile cochlear frame - a possible new mechanism of sound adaptation. It is generally accepted that the rigid frame that harbours sensory structures in the hearing organs of modern higher vertebrates has only a passive supporting role. We have discovered a contractile component in the cartilaginous cochlear frame of the lizard Teratoscincus scincus and demonstrated that the tonus of the contractile tissue can be regulated. We hypothesize a new, previously unknown mechanism of slow mechanical adaptation in the vertebrate hearing organ. The aim of the proposed project is to examine this hypothesis in more detail.
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The co-expression of visual pigments in a single photoreceptor: environmental regulation and spectral tuning. The light sensitive cells (photoreceptors) in the vertebrate retina contain filters (oil droplets) and visual pigments (opsins). These structures tune the incoming light and initiate the visual process, respectively. Exciting new research reveals that some vertebrates express more than one opsin within a single photoreceptor. We plan to examine the regulation of single and two co-express ....The co-expression of visual pigments in a single photoreceptor: environmental regulation and spectral tuning. The light sensitive cells (photoreceptors) in the vertebrate retina contain filters (oil droplets) and visual pigments (opsins). These structures tune the incoming light and initiate the visual process, respectively. Exciting new research reveals that some vertebrates express more than one opsin within a single photoreceptor. We plan to examine the regulation of single and two co-expressed opsin genes by manipulating the light environment. We expect to determine the environmental triggers for visual pigment tuning and the effects of co-expression on colour vision.Read moreRead less
Environmental regulation of opsin expression and spectral tuning in the vertebrate retina. Exciting new evidence shows that the vertebrate visual system is extraordinarily plastic and that the colour and brightness of the ambient light regulates both the spatial and temporal expression of visual pigments (opsin) genes and the degree of spectral filtering in the retina. Based on findings that more than one visual pigment can be co-expressed in a single photoreceptor type, we plan to manipulate th ....Environmental regulation of opsin expression and spectral tuning in the vertebrate retina. Exciting new evidence shows that the vertebrate visual system is extraordinarily plastic and that the colour and brightness of the ambient light regulates both the spatial and temporal expression of visual pigments (opsin) genes and the degree of spectral filtering in the retina. Based on findings that more than one visual pigment can be co-expressed in a single photoreceptor type, we plan to manipulate the light environment in order to identify and quantify the effect of different lighting regimes by morphological, spectral and molecular techniques in a concerted effort to understand the regulation of opsin expression.Read moreRead less
The evolution of colour vision in vertebrates. Colour vision plays a crucial role in the lives of many animals including vertebrates. However, very little is known about the origins of colour vision and we aim to fill this gap. Photoreceptors (cone cells) with sensitivities to different colours mediate colour vision (humans possess blue, green and red cones). This study will examine the structure, physiological responses and molecular biology of these cells in the closest living relatives of the ....The evolution of colour vision in vertebrates. Colour vision plays a crucial role in the lives of many animals including vertebrates. However, very little is known about the origins of colour vision and we aim to fill this gap. Photoreceptors (cone cells) with sensitivities to different colours mediate colour vision (humans possess blue, green and red cones). This study will examine the structure, physiological responses and molecular biology of these cells in the closest living relatives of the early vertebrates. The underlying mechanisms for spectral tuning, the genetic rate of evolutionary change and the importance of colour in visual ecology will also be examined.Read moreRead less