The Portuguese man-of-war is actually a floating colony of individuals called polyps that are all dependent on each other for survival. One large polyp forms a gas-filled, blue, translucent body that floats above the surface. Long tentacles that dangle down in the water are specialized to detect and capture prey. Other polyps are specialized for digesting prey once it is captured.

Image credits: main image, courtesy of Dr. Thomas, M. Scott, Florida Geological Survey.