Phylogeny Flashcards
Ancestral characteristic synonym
Plesiomorphic
Derived characteristic synonym
Apomorphic
Synapomorphy
Derived character/trait that is shared between two or more taxa
Monophyletic group
An ancestor and all of its descendants
Paraphyletic group
An ancestor and some of its descendants
Polyphetic group
Taxa that are not descended from an immediate common ancestor
Chordate characteristics (5)
1) Dorsal hollow nerve chord
2) Notochord
3) Pharyngeal slits
4) Post-anal tail
5) Endostyle (thyroid)
Embryonic origin of dorsal hollow nerve cord
Ectoderm
neural tube
Embryonic origin of notochord
Mesoderm
Chordata subphylums
Cephalochordata, urochordata, vertebrata
Urochordata distinguishing features
Dramatic metamorphosis, filter feeding
Cephalochordata distinguishing features
No metamorphosis, filter feeding
Echinodermata distinguishing features
Dramatic metamorphosis, pentaradial symmetry in adults, bilateral symmetry in larvae
Hemichordata distinguishing features
Three sections: proboscis, collar, and trunk, no post-anal tail but has pharyngeal slits
Vertebrata distinguishing features
Vertebrae, very diverse, usually have red blood cells, brains, sense organs, a cranium, closed circulatory system. TBH, what you think of when you think “animal”
Agnatha
Jawless vertebrae
Gnathostomata
Jawed vertebrae
Agnathan classes
Myxinoidea (hagfish)
Petromyzontida (lampreys)
Protostome
blastopore = mouth hole