KA8- Phylogenetics Flashcards
What is phylogenetic?
The study of evolutionary history and relationships between different groups of organisms using genomes
Over time, a group of closely related organisms acquire what?
Its own set of mutations which gradually alter its genome
What happens if two groups diverge?
Their genomes become distinctively different
What can changes in genomes be sued to estimate?
How long ago the groups diverged
What does phylogenetic involve?
Comparison of genome sequence data to work out the sequence of events in evolution
What are closely related species found to have?
Genomes that are very similar in their sequence of bases
What is a phylogenetic tree?
A diagram that shows the evolutionary relationships and divergence from a common ancestor
The number of differences per unit length of DNA between 2 genomes is a measure of what?
Evolutionary distance between them
What happens to mutations in molecular clocks?
They happen at a steady rate over time
Why are molecular clocks more accurate than structural data?
As they examine differences in DNA
What can molecular clocks be compared with?
Fossil evidence to construct more accurate phylogenetic trees
How have the origins of all living things been traced?
By comparing the rRNA nucleotide sequences of many organisms
Why was rRNA used as a molecular clock?
Because the genes that code for rRNA are ancient, rarely transferred horizontally and are possessed by all living things
What are the three main domains of life?
Archaea, bacteria and eukaryotes
