De substuons inserondeleons or genome rearrangements

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: different gene?c variants become dominant •  Any two species share a (possibly distant) common ancestor 15 •  •  •  •  •  Closer related organisms have more similar genomes Highly similar genes are homologous (have the same ancestor). A universal ancestor exists for all life forms. Molecular difference in homologous genes (or protein sequences) are posi?vely correlated with evolu?on ?me. Phylogene?c rela?on can be expressed by a evolu?onary tree . Phylogene?c Trees DNA is a Good Tool for Taxonomy DNA sequences have many advantages over classical types of taxonomic characters: Aardvark Bison Chimp Dog Elephant •  Leafs - current day species •  Nodes - hypothe?cal most recent common ancestors •  Edges length – ?me from one specia?on to the next –  Character states can be scored unambiguously –  Large numbers of characters can be scored for each individual –  Informa?on on both the extent and the nature of divergence between sequences is available (nucleo?de subs?tu?ons, inser?on/dele?ons, or genome rearrangements) 17 3 9/16/13 Sequences Reflect Rela?onships •  Aker working with sequences for a while, one develops an intui?ve understanding that for a given gene, closely related organisms have similar sequences and more distantly related organisms have more dissimilar sequences. •  These differences can...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online