We have always thought that all animals need oxygen to live, but new research discovered that this animal doesn't.
Researches found a unique organism that doesn't need to breathe and to produce energy.
"When we think of 'animals,' we picture multicellular creatures that need oxygen to survive, unlike many single-celled organisms including protists and bacteria," Stephen Atkinson, a senior research associate at Oregon State University's Department of Microbiology told CNN.
"In our work, we have shown that there is at least one multicellular animal that does not have the genetic toolkit to use oxygen."
The H. salminicola is a myxozoan cnidarian, a type of animal-related to jellyfish and coral. It lives inside salmon and "steals ready-made nutrients" from it, Atkinson said, instead of consuming oxygen directly.