Why crested penguins lay mismatched eggs
Extreme penguin egg favoritism could be quirk of migration
![macaroni penguins](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2016/12/121416_notebook-the-est_main.jpg?fit=860%2C460&ssl=1)
MISMATCHED OFFSPRING When macaroni penguins convene at a breeding site (shown), females lay some of the most size-mismatched eggs known among birds.
G. Crossin