“The evolutionary history of colour and vision has been closely intertwined over the last 500 million years, leading to a dazzling diversity of colours and visual systems in Mollusca,” says Suzanne.
“Surprisingly, given the range of colours and patterns in this group, nearly all molluscs are thought to be colour blind and most have poor visual acuity. Yet they showcase the greatest diversity of eye types in the animal kingdom.”
Scallops, unlike many bivalve molluscs, have eyes7. Up to 200 bright blue eyes peer out along the mantle between their two shells, looking for approaching predators. Scallops can rapidly and erratically swim short distances if needed, clamping their shells together to move by jet propulsion.
Scallop eyes are unique in the animal kingdom. The most common type of eye, like our own, uses a lens to focus light on a retina. The scallop eye uses an array of mirrors, like a telescope, to focus light onto two retinas. The structure is not found in any other animal.
“Having the genome sequence will underpin further research into this rare and fascinating feature,” says Suzanne.
Suzanne is also interested in the colour of scallop shells. “Colour can be used to attract, warn, camouflage, mimic, or even control temperature. My studies have focussed mainly on the identification of shell pigments and the molecular pathways responsible for their production in molluscs. I am particularly interested in heritable colour differences, where alternate colour morphs occur within a single species and are genetically controlled,” she says.
The power of genomics
Researchers producing genome sequences of the scallop along with other British species, which will be openly available to the research community, are part of the global effort to sequence the genomes of all animals, plants, fungi and protists on Earth.
Dr Kerstin Howe, Senior Scientific Manager at the Sanger Institute said, “The scallop assembly is of very high quality and the most contiguous of all published bivalve genome assemblies so far. It will be a very useful resource for investigations of evolutionary genomics in molluscs, growing scallops as food, population genetics, the biology of neurotoxins, and the evolution of novelties such as eyes and colouration, for many years to come.”