Organismic groups vary non‐randomly in their vulnerability to extinction. However, it is unclear whether the same groups are consistently vulnerable, regardless of the dominant extinction drivers, or whether certain drivers have their own distinctive and predictable victims. … Focusing on the fossil record of the last 300 million years, we identify clades and traits of marine ectotherms that were more prone to extinction under the onset of six hyperthermal events than during other times. … Hyperthermal‐vulnerable clades include rhynchonelliform brachiopods and bony fish, whereas resistant clades include cartilaginous fish, and ostreid and venerid bivalves. Want to read more? Click here!