Some mussels have evolved a similar feature : they are able to make part of them look like a fish even if they are blind : http://whyevolutionistrue.wordpress.c

Some mussels have evolved a similar feature : they are able to make part of them look like a fish even if they are blind : http://whyevolutionistrue.wordpress.com/2011/03/02/amazing-mimics-the-mussel-lampsilis/ http://whyevolutionistrue.wordpress.com/2011/03/02/amazing-m... Probably those spiders are the result of a similar evolutionary process.