CLADISTICS
● determination of evolutionary relationships based on common features
DNA
● deoxyribonucleic acid
● all living organisms use DNA as their genetic material
● consists the same 4 nitrogenous bases
○ adenine, guanine, cytosine, thymine
● is universal (with some exceptions) → shows that life has evolved from a common ancestor
● apes and humans share 94.8-99% of DNA
● greater number of genes in common → more closely related
Phylogeny
● Branch of biology that describes the evolutionary history of a particular species or taxonomic
group
○ Shown as tree diagrams called cladograms
Cladograms
● also called phylogeny trees
● node
○ part of the cladogram where clades branch off
○ shows where speciation/ divergence has occurred
Clades
● represent all organisms that descended from one common ancestor
● monophyletic group
● e.g. Shark and stingray
○ Class Chondrichthyes (cartilaginous fishes)
Kingdom Animalia
Phylum Chordata
Subphylum Vertebrata
Division Gnathostomata
Superclass Pisces
Class Chondrichthyes
● determination of evolutionary relationships based on common features
DNA
● deoxyribonucleic acid
● all living organisms use DNA as their genetic material
● consists the same 4 nitrogenous bases
○ adenine, guanine, cytosine, thymine
● is universal (with some exceptions) → shows that life has evolved from a common ancestor
● apes and humans share 94.8-99% of DNA
● greater number of genes in common → more closely related
Phylogeny
● Branch of biology that describes the evolutionary history of a particular species or taxonomic
group
○ Shown as tree diagrams called cladograms
Cladograms
● also called phylogeny trees
● node
○ part of the cladogram where clades branch off
○ shows where speciation/ divergence has occurred
Clades
● represent all organisms that descended from one common ancestor
● monophyletic group
● e.g. Shark and stingray
○ Class Chondrichthyes (cartilaginous fishes)
Kingdom Animalia
Phylum Chordata
Subphylum Vertebrata
Division Gnathostomata
Superclass Pisces
Class Chondrichthyes
