Higher Order Multiples
High orders of multiple births (three or more offspring in one birth) may result in a combination of fraternal (genetically different) and identical (genetically identical) siblings. The latter are also called super twins. For example, a set of quadruplets may consist of two sets of identical twins; in such a case each child has one identical and two fraternal siblings. This happens when multiple eggs are fertilized and one or more these subsequently divides into two fetuses. By analogy with monozygotic and dizygotic twins, such a combination is called dizygotic triplets. The Kübler triplets (see Elisabeth Kübler-Ross) were of this type.
Identical triplets or quadruplets are very rare and result when the original fertilized egg splits and then one of the resultant cells splits again (for triplets) or, even more rarely, a further split occurs (for quadruplets). Alternatively the original fertilized egg can split twice (to produce four embryos) and all four may survive, to produce identical quadruplets, or one of the embryos may not survive and result in triplets.
Read more about this topic: Multiple Birth
Famous quotes containing the words higher, order and/or multiples:
“The higher the climb, the heavier the fall.”
—Chinese proverb.
“In order to really enjoy a dog, one doesn’t merely try to train him to be semihuman. The point of it is to open oneself to the possibility of becoming partly a dog.”
—Edward Hoagland (b. 1932)
“If twins are believed to be less intelligent as a class than single-born children, it is not surprising that many times they are also seen as ripe for social and academic problems in school. No one knows the extent to which these kind of attitudes affect the behavior of multiples in school, and virtually nothing is known from a research point of view about social behavior of twins over the age of six or seven, because this hasn’t been studied either.”
—Pamela Patrick Novotny (20th century)