What Is a Mega Penguin?

The largest of today’s penguins reach only about chest height on an adult human, so the thought of one looking a grown person in the eye seems unlikely. Millions of years ago, though, penguins this size were real. The term mega penguin works on two levels. Used loosely, it describes a whole group: the many giant, now-extinct penguins that dwarfed every penguin species alive today. Among these giants, it is popularly used as a nickname...