Jack Russell terrier is an aggressive dog ... The Jack Russell’s character, coloring, flexibility, and intelligence were all traits that lent to this dog’s superiority as a hunting companion.

A dog owner from the Midwest noticed that her Jack Russell terrier kept playing with a very ... "[She] always [shows] this self-soothing behavior—it's similar to 'dog zoomies," Maia explained ...

The Jack-A-Poo is a small-to-medium-sized hybrid dog breed developed in the US by breeding a Jack Russell terrier with a toy ... depending on which parent’s traits are more dominant.