BIOL 551 Exam 2, tax evidence III

tax evidence: DNA

history of use: 1990s

lvl of utility -ALL

resources - molec bio lab, DNA lab

more funding needed, grant supported

what is a good thing about using molecular systematics?

allows you to see more differences

clarity of character states

what can molecular systematics be used for?

genome rearrangements

inferring sequence

direct gene sequencing

genome sequencing or across genomes

different plant genomes

mitochondrial

chloroplast

nuclear

chloroplast genome

circular, think endosymbiont theory

most used of 3

Data acquisition

extraction

PCR

seq alignment

analysis

PCR

PCR: a technique for obtaining large amounts of the

DNA region of interest

tax evidence: PCR

1980s

lg amounts quickly

provides character data

sequence alignment

Sequence alignment: assessing homology of molecular

characters

What is homology, and why is it

important to assess (for any kind

of taxonomic evidence)?

Homology is similarity due to common ancestry.

Once we've assessed homology of a particular

character, we can make comparisons ...

use synapomorphies to signal divergence and build phylogenies

Potential challenges in

working with DNA data

. Need knowledge about the gene region:

e.g., primer information, ideas on

appropriate gene regions for questions

posed, etc.

. Technical work in obtaining sequences,

analyzing