phylogenetic trees

Question 1

what is a phylogenetic tree ?

Answer 1

is a branching diagram depicting a hypothesis of evolutionary relationships among organisms

Question 2

what is the root of a tree ?

Answer 2

represents the oldest common ancestor of all members of tree

Question 3

what is a lineage (branch ) ?

Answer 3

descendants of a single common ancestor

Question 5

what is the internal node ( branch point ) ?

Answer 5

represents divergence of 2 or more groups from a common ancestor ( speciation event )

Question 6

what can descendant lineages do ?

Answer 6

continues to evolve and new (derived ) traits a rise via mutation in each lineage independently

Question 7

What are terminal nodes (tips)?

Answer 7

represent all extant descendants of the oldest common ancestor

Question 8

what does the rotating of the branch do ?

Answer 8

branches can be rotated about any node doesn’t change meaning of tree.

Question 9

what is a taxon ?

Answer 9

any named group

Question 10

how are two groups closely related to each other ?

Answer 10

two groups are more closely related if they share a more recent common ancestor

Question 11

what is an ancestral trait ?

Answer 11

plesiomorphy originated in the common ancestors of a group . may be retained , modified or lost in its descendants

Question 12

what is symplesiomorphy ?

Answer 12

shared ancestral traits

Question 13

what is a derived trait ?

Answer 13

a pormorphy - novel trait found in some descendants but never in the common ancestry