The 12 Weirdest Animal Discoveries

Two-headed shark fetus

Another photo of the two-headed shark fetus.

Another photo of the two-headed bull shark fetus. (Image credit: Patrick Rice, Shark Defense / Florida Keys Community College)

This two-headed shark fetus would be right at home as a circus attraction. In March 2013, researchers reported the discovery of this odd creature in the belly of a pregnant bull shark caught off the Florida Keys.

One of the shark's fetuses (which are live in utero in this species), had not one, but two heads. The deformity arose when the shark embryo attempted to split into twins early in development, but failed. It would not have survived long, if at all, in the wild, researchers said.

Snake eats monkey

A boa constrictor eating an adult female Purús red howler monkey. Usually boa constrictors have been known to eat smaller animals.

A boa constrictor eats an adult female Purús red howler monkey in the Brazilian Amazon. Usually the snakes have been known to eat smaller animals. (Image credit: Erika Patrícia Quintino / American Journal of Primatology, via Paul Garber)

Yikes! In August 2013, researchers captured on camera a boa constrictor eating a howler monkey whole.

Snake attacks on primates are rarely reported, making this video surprising. Usually, primates find protection in numbers, as they tend to live with family groups. In this particular case, the monkey wandered too far from its group and failed to see the boa. After the boa swallowed the monkey, the primate's outline can be seen distorting its body. [Video of Boa Eating Monkey]

Stephanie Pappas
Live Science Contributor

Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.