Frontiers Quiz
June 1997
Why would masked booby mothers bother to lay more than one egg if the elder chick consistently kills the younger one?
Click here for the answer: The second egg is "insurance." Masked booby eggs have only a 60 percent hatch rate. With the second egg, masked booby mothers bring their chances of hatching at least one chick up to 84 percent.
To find out more, read the article.
