It’s never a good sign when a living creature is born with two heads. The reason is usually genetic mutation and the cause for that could be anything from careless breeding (like a piglet was born recently on a farm in Cuba with one head and two bodies — see story below) to pollution or radiation from a nearby nuclear accident (we’re looking at you, Fukushima and Chernobyl). However, a deer fawn born with two heads in Minnesota has taken on an added air of mystery because it’s so rare to see this type of deformity among mammals in the wild and even rarer that the two-headed fetus was carried to term.
The two-headed white-tailed fawn (Odocoileus virginianus) was rare enough and strange enough (see the pictures here) to warrant a study in The American Midland Naturalist journal co-authored by Gino D’Angelo, an assistant professor of deer ecology and management at the University of Georgia’s Warnell School of Forestry and Natural Resources.
“It’s amazing and extremely rare. We can’t even estimate the rarity of this. Of the tens of millions of fawns born annually in the U.S., there are probably abnormalities happening in the wild we don’t even know about.”
A mushroom hunter found the two-headed fawn in a forest near Freeburg in southeastern Minnesota, just a mile from the Mississippi River. The fawn was “clean, dry and only recently deceased” and the mushroom picker, feeling someone might want to see it, sent it to the Minnesota Department of Natural Resources, where it was frozen until being examined there by D’Angelo, who determined that it was actually conjoined twins.
D’Angelo was able to conduct a full necropsy, a CT scan and a magnetic resonance imaging at the University of Minnesota’s Veterinary Diagnostic Laboratory. Those examinations showed that the two heads and necks were attached to a single normal body with normal fur, spots and legs. However, the insides would never have been able to function normally due to a malformed shared liver, extra spleens and two hearts that overfilled a single pericardial sac (the sac that contains and protects the heart). Despite being stillborn, the twins had been cleaned by the mother and otherwise cared for until she determined they were not alive.
The conjoined twins warranted such meticulous study because of their extreme rarity. According to their research, there have been only 19 confirmed cases of conjoined twins in wildlife between 1671 and 2006 and only five in the deer family. Of the other two cases found in white-tailed deer, both were fetuses.
“Even in humans we don’t know. We think it’s an unnatural splitting of cells during early embryo development.”
Anticipating the question, D’Angelo is just as puzzled as everyone else. For those who are interested, the twins have been preserved and are on display at the Minnesota Department of Natural Resource in St. Paul.
Now that this study is complete, perhaps D’Angelo or a professor of ‘pig’ ecology and management should take a trip to Cuba to see the piglet with one head and two bodies. As reported in Guerrillero (with gruesome pictures), the piglet was one of 12 born to a sow owned by Caridad Pelier Martínez, who is described as both a custodian and a pig farmer. Four piglets died and it’s not clear if the one with a single head and eight legs on two bodies was counted as one or two. The medical term for this is Cephalothoracopagus Siamese twins, meaning the heads are fused but the bodies are separate. While no cause was given, the new report (Google translation) hints at incestuous breeding.
“Before the deformation that can not explain, the owner speculates that perhaps the cause is that the pig that mounted the piglet (this was his first birth) was the father of it, which caused some genetic failure.”
As previously stated, conjoined twins – no matter what they are or where they are connected – are never a good sign.