Nonetheless, scientifically, the required results could be achieved by the successive interbreeding of single  colored animals that carried recessive genes for spottedness, explains scholar Nahum Sarna, and such animals are detectable by their hybrid vigor
( उत्पत्ति ३०: ३७ - ४२) प्राण्यांचे प्रजोत्पादन करण्यासंबंधी त्याच्या कल्पना योग्य नव्हत्या.