Amathayili enziwe ngezandla amagama avamile wamathayela acwebezelisiwe anomumo okhethekile futhi awavamile ukubonakala. Esikhathini esidlule, amathayili enziwe ngezandla ayenziwa ngesandla, kodwa ngokuthuthukiswa kwesayensi nobuchwepheshe, amathayili enziwe ngezandla kulesi sigaba awaqediwe wonke ngesandla, kodwa azoqedwa kanye nemishini ukuze asindise izindleko nobuqotho bawo. Amathayela enziwe ngezandla ngokuvamile angamathayili wesikhunta esithile esikhethekile esishiwo abaklami. Eziningi zazo zikhethekile, azivamile ukubonakala emakethe, futhi kungenzeka kube yizo kuphela. Ubuhle bamathayela enziwe ngezandla ubukhethekile bawo, futhi okubi kungase kube ukuthi intengo ingaphezulu kwamathayela avamile wesitimela esingaphansi.