Conjoined twins is fusion, in which a fertilized egg completely separates, but stem cells (which search for similar cells) find similar stem cells on the other twin and fuse the twins together. Conjoined twins share a single common chorion, placenta, and amniotic sac, although these characteristics are not exclusive to conjoined twins, as there are some monozygotic but non-conjoined twins who also share these structures "in utero". The most famous pair of conjoined twins was Chang and Eng Bunker (Thai: อิน-จัน, In-Chan) (1811–1874), Thai brothers born in Siam, now Thailand. They traveled with P.T. Barnum's circus for many years and were labeled
Twins in mythology Twins in mythology Twins appear in the mythologies of many cultures around the world. In some they are seen as ominous and in others they are seen as auspicious. Twins in mythology are often cast as two halves of the same whole, sharing a bond deeper than that of ordinary siblings, or seen as fierce rivals. They can represent another aspect of the self, a doppelgänger, or a shadow. However, twins can also reflect a complete opposition of the other, such as the "civilized" Gilgamesh, and the "wild" Enkidu; or in the commonly known instance of good and evil twin