Comparative retinal anatomy of anemonefishes from the Great Barrier Reef

Colour vision is used by many animals to escape predation, communicate with other individuals, find food and mates, and navigate through complex habitats. Our understanding of animal vision has contributed to the development of digital cameras, image sensors, optical devices such as telescopes and microscopes, and computer vision algorithms. Furthermore, understanding the visual performance of animals has widespread implications in neuroscience, ecology, conservation, evolution and animal welfare.

Anemonefishes (subfamily, Amphiprioninae) are a group of damselfishes comprising 30 species belonging to two genera (Amphiprion and Premnas), including the famous Orange clownfish, Amphiprion percula, and its sister-species, the Clown anemonefish, A. ocellaris a.k.a. Nemo from the Disney movie ‘˝Finding Nemo’. Most anemonefishes are zooplanktivorous with some species also feeding on algae. They are easily distinguished from other reef fishes by their highly contrasting body patterns consisting of orange, black and white stripes and their unusual biology. Anemonefishes live within large cnidarian anemones which they form a close mutualism with and have a sequentially hermaphroditic reproductive development. They are known to live in complex social hierarchies based on body size, where the two largest (most-dominant) fish are the reproductive female (largest) and male (second largest) pair, while any remaining smaller fish are subordinate (non-reproductive) juveniles/sub-adults. Together, these characteristics make them ideal to further explore how vision guides survival on the reef.
In this project, you will conduct retinal topographic analyses of the distribution of photoreceptors and neurons that process colour signals. Such techniques are useful in providing information on how animals perceive and process visual information. Using the wholemount technique allows examination of the entire retina, areas of high cell density or retinal specialization can be identified. These areas of high cell density provide greater acuity in a specific part of the visual field and usually closely reflect each species’ habitat and behavioural ecology in both terrestrial and aquatic vertebrates. You will compare different species of anemonefishes, which live in different anemones and habitats to see how their visual system aligns with their ecology

Supervisor: Dr Karen Cheney