As opposed to what arthropods have, vertebrates have this internal framework
Most vertebrates (animals with a backbone) have a skeleton on the inside of the 
body, ... get their support from the internal pressure of fluid pushing against the 
outer walls of ... All arthropods (such as crabs, lobsters, spiders, and insects) 
have... [DOC] [TLE] Invertebrate vs Vertebrate - Difference and Comparison | Diffen [PAR] The main difference between vertebrates and invertebrates is that invertebrates, 
like insects and flatworms, do not have a backbone or a spinal column.