from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Derived from a single fertilized ovum or embryonic cell mass. Used especially of identical twins.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. That has developed from a single fertilized ovum
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. derived from a single fertilized egg
Sorry, no etymologies found.
Of 5,597 monozygotic twin pairs where both were alive and had provided usable responses to CFS screening questions, we identified 140 pairs of twins who met preliminary inclusion criteria: born 1935-1985, classified as a monozygotic twin based on questionnaire responses
Therefore although I might call them "monozygotic" I wouldn't agree that they were "identical."
In "A Genetic Study of Male Sexual Orientation," a study that has now achieved almost as much renown as LeVay's, the Northwestern University psychologist Michael Bailey and Boston University's Richard Pillard compared fifty-six "monozygotic" twins (identical twins, from the same zygote, or fertilized egg), fifty-four "dizygotic" (fraternal) twins, and fifty-seven genetically unrelated adopted brothers.
Classical liberals (libertarians, basically) accept that only monozygotic twins are “created equal” and that even these will diverge as they mature.
But births of monozygotic twins are rare, roughly one in 300.
The mother assumed that she had given birth to fraternal twins (dizygotic, from two eggs) and not "identical" ones (monozygotic, two embryos developed from a single fertilized egg).
In the switched-baby cases Ms. Segal discusses, it is highly unlikely that the error would have been discovered were it not for the fact that the twins were monozygotic and thus had a striking physical resemblance.
And most of us have probably ingested meat and dairy products from livestock cloned by natural reproduction (monozygotic siblings), mechanical embryo-splitting or even nuclear transfer from an embryonic donor cell into an enucleated oocyte.
In contrast, we present here evidence for cognitive “specialist genes”: monozygotic twins are more similar than dizygotic twins in the specific cognitive ability of face perception.
Each of three measures of face-specific processing was heritable, i.e., more correlated in monozygotic than dizygotic twins: face-specific recognition ability, the face-inversion effect , and the composite-face effect .