Section 20.1 (Exam 1)

Question 1

the evolutionary history of relationships among organisms

Answer 1

Phylogeny

Question 2

diagrammatic reconstruction of the evolutionary history of species, populations, and genes

Answer 2

Phylogenetic tree

Question 3

Phylogenetic trees used to be based on?

Answer 3

physical structures, behaviors, and biochemical attributes

Question 4

Now, phylogenetic trees are made by using?

Answer 4

genome sequencing, which allows biologists to reconstruct the history of life in ever greater detail

Question 5

series of ancestor and descendant populations

Answer 5

lineage

Question 6

When a lineage divides into two, what does it form?

Answer 6

a node

Question 7

any group of species that has a name (vertebrates, eukaryotes, bacteria)

Answer 7

Taxon (plural, taxa)

Question 8

a taxon that consists of all of the descendants of a single common ancestor

Answer 8

clade, monophyletic group

Question 9

two species that are the closest relatives of one another

Answer 9

sister species

Question 10

two clades that are the closest relatives of one another

Answer 10

sister clades

Question 11

features that are shared by two or more species that were inherited from a common ancestor

Answer 11

Homologous (e.g. vertebral column)

Question 12

trait that ancestors and all descendants have

Answer 12

ancestral trait

Question 13

trait that came from the ancestral trait, but is different

Answer 13

derived trait

Question 14

derived traits shared among a group; they are viewed as evidence of the common ancestry of the group

Answer 14

synapomorphies

Question 15

what is it called when independently evolved traits subjected to similar selection pressures become superficially similar

Answer 15

convergent evolution

Question 16

Functionally similar structures that have independent origins are called ____________.

Answer 16

analogous

Question 17

Evolutionary reversal

Answer 17

A character reverts from a derived state back to the ancestral state

Question 18

Similar traits generated by convergent evolution and evolutionary reversals are called ____________.

Answer 18

homoplasies

Question 19

What are synapomorphies?

Answer 19

derived traits shared among a group; they are viewed as evidence of the common ancestry of the group

Question 20

What is convergent evolution?

Answer 20

when independently evolved traits subjected to similar selection pressures become superficially similar

Question 21

What is a clade/monophyletic group?

Answer 21

a taxon that consists of all the descendants of a single common ancestor