chordate
Spinal column creature
A chordate is any animal possessing a notochord—a flexible rod running along the back—at some stage of development.
The phylum Chordata includes vertebrates (mammals, birds, fish, reptiles, amphibians) as well as some invertebrates like sea squirts and lancelets.
In vertebrates, the notochord develops into the spinal column.
Humans are chordates, though our notochord appears only briefly during embryonic development.
Primitive marine chordate
- tunicateCoated marine invertebrate
- sea squirtBarrel-shaped marine invertebrate
- salpPlanktonic tunicate
- filter feederAnimal straining waterborne nutrients
sessile · benthic · pelagic · larval stage · metamorphosis · marine
Vertebral column, or courage
- vertebraeInterlocking bones of spine
- spineColumn of vertebrae
- skullHead's bone casing
- craniumSkull bone structure
fish · amphibian · reptile · bird · mammal · tetrapod · jaw · endoskeleton
Major classification rank
- notochordEmbryonic axial support structure
- phylogeneticsScience of ancestral relationships
- cladisticsClassification by common descent
- sister groupNearest branch in phylogeny
monophyletic · subphylum · classification · Chordata · echinoderm
Embryonic axial support structure
- neural tubeEmbryonic nervous system precursor
- segmentationDivision into sections
- thyroid glandNeck organ controlling metabolism
- pharynxMuscular throat cavity
Earliest Paleozoic period
- fossil recordRemains documenting prehistoric life
- phylogenyEvolutionary relationships among organisms
- common ancestorOrigin point of descendants
- Burgess ShaleCambrian lagerstätte in Canada
diversification · speciation · homology · adaptation · Paleozoic · ancestry · morphology
lancelet
Primitive marine chordate
- tunicateCoated marine invertebrate
- sea squirtBarrel-shaped marine invertebrate
- salpPlanktonic tunicate
filter feeder · sessile · benthic · pelagic · larval stage · metamorphosis · marine
backbone
Vertebral column, or courage
cranium · fish · amphibian · reptile · bird · mammal · tetrapod · jaw · endoskeleton · cartilage
phylum
Major classification rank
- notochordEmbryonic axial support structure
- phylogeneticsScience of ancestral relationships
- cladisticsClassification by common descent
sister group · monophyletic · subphylum · classification · Chordata · echinoderm
notochord
Embryonic axial support structure
- neural tubeEmbryonic nervous system precursor
- segmentationDivision into sections
- thyroid glandNeck organ controlling metabolism
Cambrian
Earliest Paleozoic period
- fossil recordRemains documenting prehistoric life
- phylogenyEvolutionary relationships among organisms
- common ancestorOrigin point of descendants
Burgess Shale · diversification · speciation · homology · adaptation · Paleozoic · ancestry · morphology
chordateinvertebrate
Animal sans backbone
arthropod · mollusk · annelid · cnidarian · echinoderm