“And let birds fly” – it is the usual way of the world that a flesh-and-blood king builds a palace and settles occupants in the upper and lower levels. Does he, perhaps, do so in its air space? The Holy One blessed be He, however, settles occupants even in the air space, as it is written: “And let birds fly above the earth…”
“God created the great serpents and every living creature that crawls, with which the water swarmed by their species, and every winged bird in its kind, and God saw that it was good” (Genesis 1:21). “God created the…serpents [hataninim]” – Rabbi Pinḥas said in the name of Rabbi Aḥa: Taninim is written without a yod12Yod being the sign of the plural. – this is Behemoth and Leviathan, that have no mates. Rabbi Shimon ben Lakish said: Behemoth has a mate, but has no desire [to mate], as it is stated: “The sinews of its testicles are knotted” (Job 40:17). Rav Huna said in the name of Rav Matna: The peacock comes from a single white-colored drop,13Sperm. and yet it has three hundred and sixty-five colors, corresponding to the number of days in the solar year. Rabbi Yirmeya Kahana asked Rabbi Shimon ben Lakish: ‘One who crossbreeds sea animals, what is the halakha?’14It is forbidden to crossbreed animals (Leviticus 19:19). He said to him: ‘Also in their regard it is written: “By their species.”’15Alluding to the concept that different species should not be interbred. With this, ben Lakish spread out his net for Kahana.16He sought to stifle any further questions. Kahana raised an objection: ‘Is “by their species” not written regarding fish as well?’17That certainly does not allude to a halakha that they should not be interbred, as that is an impossible act. With this, Kahana spread out his net to trap Rabbi Shimon ben Lakish. How, indeed can this be done?18The mixing of two species of fish. Rabbi Yona said: ‘I can explain it regarding driving animals:19The Torah also forbids tying two different species together and forcing them to move along together (Deuteronomy 22:10). One brings two fish, a mairon and an asparon,20Two different species of fish. ties them together with reed-grass, and leads them along in the river or the sea. It is prohibited to do so, due to the prohibition of diverse kinds, as we learned:21Kilayim 8:2. The diverse kinds that were mentioned regarding driving them [together], may not be used to plow, to haul, or to pull together. Thus it is stated: “And every living creature that crawls, with which the water swarmed by their species”’ (Genesis 1:21).22Indicating that the prohibitions involving diverse species apply to sea life as well. “And every winged bird” (Genesis 1:21) – this is the peacock.