Science & technology | Aggressive dogs

How XL Bullies became such dangerous dogs

Generations of breeding are to blame

An XL Bully named Pippa enjoys a run and a walk on a private and secure dog walking field.
Photograph: Getty Images

IN 2021, WHILE visiting a friend’s house in the Welsh town of Caerphilly, ten-year-old Jack Lis was fatally attacked by a dog called Beast. It mauled him so severely that Jack’s mother could identify her son’s body only from his shoe.

This article appeared in the Science & technology section of the print edition under the headline “Heir of the dog”

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