Of the nearly 60 million pet cats in the United States, one of the most common is the classic tabby—a coat pattern that features stripes, dots, and swirls and what looks like an M imprinted on the cat’s forehead.

As popular as tabbies are (think Garfield the cat), scientists know little about how they get this distinctive appearance.

In a study published this week in Nature Communications, scientists report that the genes that set up the tabby pattern are activated in an embryo’s skin cells before the cat’s fur develops. The early skin cells even mimic tabby stripes under the microscope, a discovery never seen before in embryonic cells.

This unique genetic process may be the same