As to the fundamental law of genetics, in which animals and plants cannot diversify beyond their genetic bounds that the Lord has set, in other words, that living things can only bring forth after their kind, the Prophet taught:
“God has made certain decrees which are fixed and immovable; for instance, God set the sun, the moon, and the stars in the heavens, and gave them their laws, conditions and bounds, which they cannot pass, except by His commandments; they all move in perfect harmony in their sphere and order, and are as lights, wonders and signs unto us. The sea also has its bounds which it cannot pass. God has set many signs on the earth, as well as in the heavens; for instance, the oak of the forest, the fruit of the tree, the herb of the field, all bear a sign that seed hath been planted there; for it is a decree of the Lord that every tree, plant, and herb bearing seed should bring forth of its kind, and cannot come forth after any other law or principle.”
(Joseph Smith, Teachings of the Prophet Joseph Smith, p. 197-198)
As for the false notion of spontaneous generation, also called abiogenesis, in which non-living matter becomes living tissue on its own, the Prophet taught:
“Where was there ever a son without a father? And where was there ever a father without first being a son? Whenever did a tree or anything spring into existence without a progenitor? And everything comes in this way.”
(Joseph Smith, Teachings of the Prophet Joseph Smith, p. 373)
