Researchers have identified four new species of 'Elvis worms', named after singer Elvis Presley because their iridescent scales reminded scientists of his sequined jumpsuits. They also filmed the worms fighting each other and "dancing" before attacking. Named Peinaleopolynoe goffrediae, P. mineoi, P. orphanae; and P. elvisi, the species live on seafloor, where it's too deep for light to penetrate.