Тосефта к Дварим 14:7

For what reason did they say that the honey of bees is permitted? Because they do not discharge it; rather, they ingest it. The honey of zizin (a species of wild bee or locust) is forbidden, for it [consists of] nothing but secretions. Rabbi Shimon says, what does the twofold repetition of "camel" and "camel" (Lev. 11:4 and Deut. 14:7) come to teach? To include the camel that is born from a cow, which is like one born from a female camel, but if its head and most of its body are similar [in appearance] to its mother (i.e., the cow), it is permitted to be eaten. And the Sages say, that which emerges from the unclean is unclean, and that which emerges from the clean is clean, for no unclean livestock can be born from one that is clean, and no clean [livestock] can be born from one that is unclean, and no large livestock (i.e., a cow) can be born from small livestock (i.e., a sheep or goat), and no small [livestock] from a large one, and no human from all other species, and no other species from a human, even though they said^*alt., "because they said" (see Minchat Bikkurim); Minchat Bikkurim writes that the printed version ("even though they said") can potentially be understood as explaining that even though there are other animals with a nine-month gestation period, none of these can bear a human child, and vice-versa; see also Minchat Eretz Yisrael (stating that the received text is defective) that small clean livestock gives birth at five months [of gestation], [and] large clean livestock at nine months, [and] large unclean livestock at twelve months, a dog at fifty days, a cat at fifty-two days, a pig at sixty days, a fox and all the sheratzim at six months, the wolf and the lion and the bear and the panther and the leopard and the elephant and the monkey and the hedgehog (kipod) at three years, and the snake at seven years. § Dolphins give birth to and raise their young like humans. Unclean fish spawn [their young], [and] clean fish lay eggs. § The digestive track of fish and fetuses [of animals] may not be eaten, except from an expert. Fowl are eaten if there is tradition [that a particular species is kosher]. A hunter is believed to say, "This fowl is clean."