sentence: Most amphibians have four limbs, except for caecilians.
sentences_before: The skeletal system of amphibians are similar to other four-legged animals. They have a spine, rib cage, long bones such as the humerus and femur. They also have short bones such as the phalanges, metacarpals, and metatarsals.
sentences_after: The bones in amphibians are hollow and do not weigh much.
concept_name: amphibian
headings: Amphibian Anatomy Senses and skeletal system
categories: Amphibians