According to the 2005 CBC article:
1942 – 1944 – Auschwitz becomes the centre of the Nazi’s “Final Solution” – the extermination of all Jews living in the parts of Europe occupied by the Third Reich. Jews arriving in packed railcars are selected right at the arrival platform by SS doctors as being “fit” or “unfit” for labour.
As many as 75 per cent of Jewish arrivals are declared “unfit” and are immediately sent to the gas chambers. More than half of those declared “fit” subsequently die from starvation, disease, forced labour, execution, torture or medical experiments. Dr. Josef Mengele, the most notorious of the SS doctors at Auschwitz, specializes in the study of twins and dwarfs.