Chordates vs Vertebrates: Key Differences Explained
Chordates are animals with a notochord at some life stage; vertebrates are the subgroup that replace it with a backbone.
People see a fish skeleton and assume “vertebrate” and “chordate” are synonyms, forgetting jelly-like lancelets and sea squirts that never grow bones.
Key Differences
Chordates include lancelets, tunicates, and vertebrates. Vertebrates add vertebrae and a skull. Only vertebrates have jaws and complex brains.
Examples and Daily Life
Your pet dog is both; a tunicate stuck to a pier is only a chordate. That’s why sushi fish and aquarium corals sit on different branches of your family tree.
Is a shark a chordate or vertebrate?
Both—sharks have a notochord early on and later grow vertebrae.
Do humans have a notochord?
Yes, briefly as embryos before it becomes the spinal column.
Can an animal lose its notochord?
Tunicates absorb theirs as adults, keeping only gill slits.