Two-Headedness

I remember when I was growing up in Spencer, there was a farmer who had a two-headed cow born one spring. The calf was given the name "Jewel" and was exhibited at the Black Walnut Festival in the fall. It died shortly after.

When I taught genetics, we always described the cases of identical twins that did not quite make the "split". These conjoined twins are often the source of much interest. In the human realm, Chang and Eng Bunker were the original "Siamese" twins discovered by P.T. Barnum. This couple was hired by Barnum and became wealthy landowners of that era. Sadly, Chang and Eng were joined only by a chest ligament and could have easily been separated if the medical advances were what they are today.

We hear of conjoined twins that are joined at the head and surgery may be a possibilty in trying to separate the two individuals. This is not possible if there is a sharing of systems or incomplete incomplete development of essential body structures.

Such is the case Abby and Britty Hensel. These two gals are truly amazing!

Abigail "Abby" Loraine Hensel and Brittany "Britty" Lee Hensel (born March 7, 1990, Carver County, Minnesota, United States), are highly symmetric dicephalic parapagus conjoined twins, and further, tribrachius, bipedus. (How is that for specifics?) They have two spines and separate half-sacrums, which converge distally within a slightly broad pelvis. They each control and sense their corresponding arm and leg; a third, rudimentary central arm was amputated in infancy.

Each of the twins manages one side of their conjoined body and they are quite ambidextrous and coordinated in both their arms and legs when both hands or both legs are required. By coordinating their efforts, they are able to walk, run and ride a bicycle normally — all tasks that they learned at a normal speed. They each write with their corresponding hand. Together, they can type on a computer keyboard at a normal speed. Their sense of touch is partitioned to their own body half, which shades off at the midsagittal plane such that there is a small amount of overlap at their midline. They enjoy hobbies and sports including volleyball, kickball, swimming, basketball, and cycling. They also play the piano and are avid computer users. They enjoy softball, digital photography, the internet, social networking, and talking on the telephone. When they go to the cinema, they pay for two tickets.

They both successfully passed their driver's license exam, both the written and driving tests. They had to take the tests twice, once for each twin. Abby controls the pedals, radio, heat, defogger etc., Brittany controls the turn signal and lights and together they control the steering wheel. They also want to visit the UK, so they can both have a chance to use their opposite controls.

They both graduated from high school in 2008. They began college at Bethel University in St. Paul, Minnesota, USA.

In conversation, they are clearly distinct persons, with distinct likes and dislikes. Despite sharing a body, the twins' preferences in food, clothing color, etc. differ. Some of their clothes are altered by their seamstress so that they have two separate necklines in order to emphasize their individuality. They will usually have separate meals, but sometimes will share a single meal for the sake of convenience (e.g., each takes a bite of the same hamburger). Abigail is better at mathematics and Brittany is better at writing. For tasks such as responding to e-mail, they type and respond as one, anticipating each other’s feelings with little verbal communication between them. In such cases as the latter, their choice of grammatical person is to use the first person singular (I) out of habit when they agree, but when their responses do differ, they use their names in the third person singular (you).

There is some concern about their ability to have continued good health because only four known sets of conjoined twins who share an undivided torso and two legs have ever survived into adulthood, and most have congenital heart defects or other organ anomalies. None have shown up in the Hensels' case. They have so far had no desire to make themselves available for any medical studies. They intend to make a rather limited number of media appearances in the future, primarily just to appease the world's curiosity and to reduce the number of people who might otherwise be taken aback by their unusual body configuration. They dislike intensely being stared at or photographed by strangers while going about their private lives. They expect to date, get married, and have children. They hope that by providing some information about themselves they will be able to lead otherwise fairly typical social lives as together they continue to make new friends.

Here is The Learning Channel clip produced when the girls turned 16. What great inspirations for us all!