Weekly Online Lesson Online Lesson Archive Grade Level: 8-12 Subject: Biology/Anatomy

Conjoined Twins

A London appeals court ruled Friday, September 22, 2000, that doctors may operate to separate 45-day-old conjoined twins against the wishes of the parents.

"If it’s God’s will that both our children should not survive then so be it,” the parents said. "Why should we kill one of our daughters to enable the other one to survive?"

The twin girls, joined at the lower abdomen, were born on August 8 at St. Mary’s Hospital in Manchester. Doctors said the girls, identified only as Jodie and Mary, will both die within months if they remain together. However, Jodie is a relatively strong, healthy baby and stands a good chance of living a normal life if the two are separated.

“I freely confess to having found it truly difficult to decide—difficult because of the scale of the tragedy for the parents and the twins, difficult for the seemingly irreconcilable conflicts of moral and ethical values and difficult because the search for settled legal principle has been especially arduous and conducted under real pressure of time,” said Justice Ward, reading the court’s decision.

For more on Baby Jodie and Baby Mary, watch this RealVideo clip from ABCNEWS.com explaining the ethical and medical dilemma.

This week's online lesson is about conjoined twins, often referred to as Siamese twins. The purpose of this lesson is not to shock or sensationalize, but to better help you better understand the unusual physical and emotional bonds of conjoined twins and learn more about the science behind their development.

Twinstuff

Start by visiting Twinstuff.com, a site filled with information about identical and fraternal twins. What's the difference? Click What Types of Twins Are There? to find out. The first section explains how identical and fraternal twins are formed. The page also gives statistics of the number of twins (or multiples) born in the U.S. Are there more or fewer twins born today than 30 years ago? Can dizygotic twins be opposite sexes? What about monozygotic twins?

Return to the home page and click Conjoined Twins, where you will learn about these extremely rare births. Read how conjoined twins form and why survival rates are so low. You will also find the scientific names and descriptions of conjoined twins. Which type is the most common? Which types are difficult or impossible to separate?

Zygote

Zygote, a developmental biology web site, contains several resources about conjoined twins. The first page, Types of Conjoined Twins, repeats some of the information you read about classifications and how conjoined twins form. What's unique to this page are its three skeletal images of such twins.

The second resource is a Social History of Conjoined Twins. This brief but fascinating history gives an account of conjoined twins from early European history through the present. How were these individuals treated by the public? How did most earn a living?

Siamese Twins

A popular term for conjoined twins is "Siamese twins." The term comes from Eng and Chang Bunker, famous conjoined twins who were born in Siam (now Thailand) in 1811 and later emigrated to the United States. For a brief synopsis of the lives of the Siamese twins, visit the Eng and Chang site at the University of North Carolina (the state where they eventually settled).

For a more detailed treatment of the lives of Chang and Eng, read A Hyphenated Life by Page Chichester (this article appeared in BlueRidge Country magazine). This account goes into much greater depth about Chang-Eng's youths, careers and fortunes, marriages, and deaths. Did the twins ever fight? How did Chang die? Could the twins have been separated had they lived today?

One final resource you may like to visit is Sideshow: Conjoined and Parasitic Twins. As the name suggests, this site is about famous sideshow performers. In the past many conjoined twins—including Eng and Chang Bunker—made a living entertaining the curious. This site introduces you to some of the most famous of these. Click Next to progress through the slide presentation.

© Copyright 2002
Learners Online, Inc.