Crab Camouflage

The Crab Camouflage game was a citizen science game developed for the Natural History Museum in London, as part of their Colour and Vision exhibition. In the first two weeks alone 60,000 crabs were spotted by over 1,000 players. The data was used for a research publication and written about in The Conversation.

The aim of the game was to spot crabs against background images of their habitats. The crabs were found in rockpools, musselbeds, and mudflats, and photographed by members of the Sensory Ecology research group at the University of Exeter. The cropped crabs were then presented against photos of the three habitat types. The game was played either as a human, or a pollock (a type of fish) – each has a different visual system, with humans seeing in three colours (red, green, blue) and pollock seeing in just two (yellow, blue).

The speed of players spotting crabs told the researchers whether the crabs have evolved camouflage that is specific for the habitat that they were found in, whether certain habitats are generally better for hiding in, and whether the crabs might have evolved to be better camouflaged from their usual predators.

When someone contributes to citizen science, it seems right that they also have access to the results. One thing we did differently with this game is to show the players the results in real-time. There were three results screens that updated each time someone played the game, and were presented to the player at the end of each game – instead of telling people what the answer was, they had a chance to think about what the latest results meant.

Being the very first person to find out something new about the world is one of the best things about doing science – it is what makes it exciting and important – but science 'public engagement' and education usually misses this critical aspect. Hopefully our small experiment in opening up citizen science a little more brings us a step closer to providing real access to the process and fundamental motivation of science.

As always, the code for the game is available open source.