→ languagelog.ldc.upenn.edu/nll/?p=2282#comment-65613

> "How long would it take a sheep to sink?" was a question posed to East Bay librarians. According to a story by Elaine Marshall in Diablo magazine, the librarians couldn't come up with an answer.

> Personals consulted experts at UC Davis Veterinary Extension. Dr. Ben Norman said that sheep "do very well" in the water. "They have a rumen, a big gas bag stomach, that keeps them from sinking. They float high and swim well."

> Cows have a similar stomach structure to sheep, said Norman. As soon as the rumen develops, the animal is kept afloat by its natural life preserver. At least half the cows stranded on an offshore island in Hurricane Carla 30 years ago were able to survive by swimming three to seven miles to the shore, said the veterinarian.

> Dr. John Glenn was a little less enthusiastic. "The only times they ever get into the water is when they cross steams. . . . They float but they are not Olympic swimmers." Wet fleece is not an important factor, said Glenn. "I have never heard of a sheep drowning unless it was trapped under water upside down."