1. The Bible does not say explicitly what the limits of variation within the created kinds (or "Baramins") may be, although the repeated reference in Genesis 1 to reproducing "after their kinds" seems to suggest interfertility as a key

2. Aecial and telial host range, interfertility, teliospore dimensions, and amount of nuclear DNA were determined for Puccinia recondita collected either worldwide from species of cultivated wheats (Triticum aestivum and Triticum turgidum ssp. durum and rye (Secale cereale), or from wild emmer (Triticum turgidum ssp. dicoccoides) and four species of wild wheat (Aegilops) in Israel.