This handsome pair were found under a mango tree in the forests of Viana municipality in southeastern Brazil.
Since their discovery in 2001, the male conjoined twins have been placed in a solution of 70 percent ethanol to help preserve their tissue, waiting for a proper scientific investigation. Fortunately, researchers from the State University of Northern Rio de Janeiro have finally taken up the honor of studying this truly precious specimen after spending years in the Laboratorio de Mastozoologia.
The researchers believe the bats were either stillborn or died shortly after being born as their placenta was still attached to their shared body. However, out in the big bad world of mother nature, it's unlikely they would have survived longer than a few days anyway.
“We have no information, however, if this specimen was alive at the moment it was collected,” the researchers explain in a recent study published in the journal Anatomia Histologia Embryologia.
The researchers took X-ray images (below) of the bats to reveal they share two complete forelimbs and two complete hind limbs, just like a regular bat. However, they have two separate spines that branch down into a single lumbar region (the bottom of the spine).
For the record, they only have a single penis. However, ultrasonic images revealed they do have two separate similarly-sized hearts.
The twins are part of a genus of bats known as Neotropical fruit bats (Artibeus), which consists of 21 species of bats, all native to either Central or South America.
This is just the third pair of conjoined twin bats ever recorded, despite bats being widely studied both in the lab and in the wild. In humans, conjoined twins are comparatively well understood and documented. Statistics vary from region to region, but the phenomenon could be as common as one in 200,000 in the US and even one in 2,800 in India. Archaeologists have even found records of conjoined humans dating back to the sixth millennium BCE.