heterochromia

With a small flick of his finger or riding crop, a person would either be sent to the left or to the right, to the gas chamber or to hard labor. Mengele would get very excited when finding twins. The other SS who helped unload the transports had been given special instructions to find twins, dwarfs, giants, or anyone else with a unique hereditary trait like a club foot or heterochromia (each eye a different color). Mengele's seeming omnipresence on the ramp stemmed not only from his selection duty, but his additional appearance when it was not his turn as selector to ensure twins would not be missed.

As the unsuspecting people were herded off the train and ordered into separate lines, SS would shout "Zwillinge!" ("twins!"). Parents were forced to make a quick decision. Unsure of their situation, already being separated from family members when forced to form lines, seeing barbed wire, smelling an unfamiliar stench - was it good or bad to be a twin?

Some parents did announce their twins. Some relatives, friends, or neighbors would announce the twins. Some mothers tried to hide their twins. The SS and Mengele would search through the surging ranks of people in search of twins and anyone with unusual traits. While many twins were either announced or discovered, some sets of twins were successfully hidden and walked with their mother into the gas chamber.

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