After catching a bull shark in the Gulf of Mexico on April 7, 2011, a fisherman opened the animal up to find a shocking sight: The shark’s two headed baby.
The little shark was still alive, so he handed it over to experts at Michigan State University who ran extensive tests. The scientists quickly realized this was a single shark, rather than conjoined twins. The fisherman, it turned out, had discovered the first two-headed bull shark ever recorded.
The tests conducted at Michigan State included an MRI that showed the shark’s two distinct heads, hearts and stomachs, and how the body joined back together to form a single tail.
The condition, known as axial bifurcation, occurs when an embryo does not successfully split into two separate organisms. While the reasons for the deformity are not clear, there have been suggestions that the 2010 Deepwater Horizon oil spill could be a contributing factor.
Had the shark survived, it would not have lived long in the wild, explained Michael Wargner, a researcher at Michigan State University.
"When you're a predator that needs to move fast to catch other fast-moving fish ... that'd be nearly impossible with this mutation," he told The Independent.