It’s the question every parent fears: Who is your favorite child? In the case of Magellanic penguins—if their chicks could ask—the answer is the most egalitarian: both of them! Many animals with multiple offspring make tough choices about distributing resources to their brood. Many runts don’t survive because they can’t compete or because their parent must favor those offspring that are most likely to survive and thrive.
In Print: November 1, 2019