Dead duck a good fuck?

Which of the following is most noteworthy?

1. Some mallards are homosexual.

2. A mallard was recently, for the first time ever, observed to copulate with a dead mallard.

3. A Dutch researcher observed this act of duck necrophilia for some 75 minutes.

4. An article recounting the duck necrophilia is the most emailed Guardian article.

5. Ducks can fuck for 75 minutes.