sentence2_structure: Backbone<>is<>another name for the vertebral column$$$Backbone<>is another name for<>the vertebral column
sentence1: Of course, as you know already, lots of vertebrates share in having a segmented 'backbone', or vertebral column made of bone, from which the group gets its name.
sentence2: Backbone is another name for the vertebral column.
question: What is another name for the vertebral column?