Jellyfish engineered with 12 heads

Animals with many heads are rare in nature, suggesting that two or more heads usually aren't better than one — having more than one head results in costs with no immediate matching benefits.

However, (researcher Bernd) Schierwater noted that corals, which are animals, often form colonies by adding heads to a common stalk, each of which connect to a common gut, just as with the modified jellyfish that the researchers created.