Chpt 25: (11) Phylogeny

Question 1

monophyletic group

Answer 1

the only valid evolutionary group

aka clade; group with common ancestor; represented by a node on the tree

Question 2

outgroup

Answer 2

group of organism with characteristics that are ancestral to the group of interest

Question 3

Polyphyletic group

Answer 3

a group characterized by one or more homoplasies

Question 4

paraphyletic group

Answer 4

a group containing a common ancestor, but not all of its descendants

exp from class was when birds were excluded from the reptile group

Question 5

Plesiomorphy

Answer 5

a character state found in the ancestor of the group

Question 6

Node (of a phylogenetic tree)

Answer 6

represents a shared ancestor between organisms that branch from it

Question 7

Parisomony

Answer 7

when there are multiple approaches to creating a phylogenetic tree, but the simplest one (with the fewest evolutionary steps) is assumed to be the most correct

Question 8

MICROevolution

Answer 8

evolution in a single species that takes place within a population, over a generation

Question 9

what a 1 means on the phylogenetic matrix

Answer 9

means the trait is DERIVED; NOT found in the root group on the tree

Question 10

what a 0 means on the phylogenetic matrix

Answer 10

means the trait is ancestral; found in the root group on the tree

Question 11

Apomorphy

Answer 11

derived characters that arise AFTER an organism diverges from the group (on the phylogeny tree)

Question 12

Homologous structures

Answer 12

(phylogeny tree structures that) belong to species of the same evolutionary origin but serve a different function

exp. like the arm of a man and seals flipper. Both mammals with a limb similar in construction, bones, joints tendon s etc. but has a completely different use.

Question 13

Analogous structures

Answer 13

(phylogeny tree structures that) are those from species with different evolutionary origins but serve a similar purpose

exp. the wing of a bee and the wing of a bird. Totally different species but same organ used to fly.

Question 14

a type of homoplasy

Answer 14

analogous structure

Question 15

Abiogenesis

Answer 15

the original evolution of life from inorganic/inanimate material

Question 16

convergent evolution

Answer 16

the independent evolution of similar traits in distantly related organisms (d/t similar environmental pressures)

exp. from class was the trees from Arizona and Madagascar that has similar phenotypes

Question 17

Macroevolution

Answer 17

evolution that results in speciation

Question 18

homoplasy

Answer 18

when a character appears in multiple groups, independently; not from a shared ancestor

A homoplasy is a shared character between two or more animals that did not arise from a common ancestor.

Question 19

analogous structure is a type of

Answer 19

homoplasy

Question 20

Synapomorphy

Answer 20

shared, derived characters that indication homology

Question 21

Homology

Answer 21

similarity in characters resulting from common ancestry