Chapter 16

Question 1

phylogeny

Answer 1

evolutionary history of relationships between organisms

Question 2

phylogenetic tree

Answer 2

diagrammatic reconstruction of phylogeny

Question 3

lineage

Answer 3

series of ancestor and descendant populations

Question 4

node

Answer 4

split in the phylogenetic tree when an ancestral population divides into two non-interacting descendant populations

Question 5

root

Answer 5

common ancestor of all organisms in the tree

Question 6

taxon

Answer 6

any group of species that we designate with a name

Question 7

clade

Answer 7

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

Question 8

sister species

Answer 8

two species that are each other’s closest relatives

Question 9

sister clades

Answer 9

two clades that are each other’s closest relatives

Question 10

systematics

Answer 10

the study and classification of biodiversity

Question 11

homologous

Answer 11

features shared by two or more species that have been inherited by a common ancestor

Question 12

ancestral trait

Answer 12

a condition that other traits can evolve from

Question 13

derived trait

Answer 13

the trait that comes from the ancestral trait

Question 14

synapomorphies

Answer 14

derived traits that are also evidence of the common ancestry of a group of organisms

Question 15

convergent evolution

Answer 15

similar traits may evolve independently in different lineages

Question 16

evolutionary reversal

Answer 16

a character may revert from a derived state back to an ancestral state

Question 17

homoplasies

Answer 17

similar traits generated by convergent evolution and evolutionary reversals

Question 18

ingroup

Answer 18

group of organisms of primary interest in a phylogenetic study

Question 19

outgroup

Answer 19

species or group closely related to the ingroup but known to be outside of it

Question 20

parsimony principle

Answer 20

preferred explanation of observed data is the simplest one

Question 21

what are methods for reconstructing phylogenies?

Answer 21

morphology, development, palaeontology, behaviour, molecular data

Question 22

morphology

Answer 22

presence, size, shape, and other attributes of body parts

Question 23

how does development reveal evolutionary relationships?

Answer 23

some organisms exhibit similarities in early development stages only

Question 24

how does palaeontology reveal evolutionary relationships?

Answer 24

fossils provide important evidence that helps distinguish ancestral from derived traits

Question 25

behaviour

Answer 25

some behavioural traits are culturally transmitted and others are genetically inherited

Question 26

molecular clock

Answer 26

rates of molecular change are constant enough that they can be used to predict evolutionary divergence times

Question 27

binomical nomenclature

Answer 27

system of naming organisms

Question 28

what are the two components of a scientific name?

Answer 28

genus name and then species

Question 29

what formatting is used in a scientific name?

Answer 29

italics

Question 30

which letters in a scientific name are capitalised?

Answer 30

the first letter of the genus name

Question 31

what is the order of all the classifications, from most general to most specific?

Answer 31

kingdom, phylum, class, order, family, genus, species

Question 32

polyphyletic

Answer 32

a group that does not include its common ancestor

Question 33

paraphyletic

Answer 33

a group that does not include all the descendants of a common ancestor

Question 34

monophyletic

Answer 34

taxon contains and ancestor and all descendants of that ancestor, and no other organisms