Lecture 19 Vocab and Pre-reading

Question 1

what does natural selection result in

Answer 1

allele frequencies changing from generation to generation

Question 2

new mutations that are deleterious and eliminated by natural selection have..

Answer 2

no long term evolutionary impact

Question 3

what was a key piece of darwin’s work

Answer 3

his sketch of the earliest phylogenetic tree

Question 4

what did his image capture

Answer 4

one species could give rise to two or more descendant species over time

Question 5

uncertainty in the branching pattern of a phylogenetic tree is

Answer 5

polytomy

Question 6

shared derived traits are

Answer 6

traits shared among smaller group

Question 7

ancestral trait

Answer 7

traits shared among larger group

Question 8

what is evolution

Answer 8

a scientific theory that all life is related through descent with modification from common ancestors

Question 9

analogous

Answer 9

describes similar characters that evolved independently in different groups as a result of similar selection pressures

Question 10

analogy defines

Answer 10

physical or behavioral similarity in terms of functions between unrelated species

eg: humming bird and bumble lee pollinating

Question 11

branch

Answer 11

shows path of transmission of genetic information from one gen to the next

Question 12

character

Answer 12

anatomical physiologyor molecular feature of an organism that varies among taxa
eg;bone shape, genetic sequences

Question 13

character state

Answer 13

the observed condition of a character
(the presence or lack of something

Question 14

convergent evolution

Answer 14

distant related organisms independently evolve to look or act similar because they live in similar places

Question 15

fitness

Answer 15

measure of the extent to which an individual’s genotype is represented in the next generation

Question 16

homologous

Answer 16

describes phenotypes that are similar in different species because of descent from a common ancestor

Question 17

homology

Answer 17

characters(phenotypes) that are similar in different species because of descent from a common ancestor

Question 18

monophyletic group

Answer 18

shares a single common ancestor and also included all of the descendants of that common ancestor

Question 19

most recent common ancestor

Answer 19

the most recent individual from which all the organisms of the set are descended

Question 20

node

Answer 20

point where the branch splits, representing the common ancestor from which the descendants species diverged

Question 21

out group

Answer 21

organisms that has an older common ancestor of the group of interest

Question 22

parsimony

Answer 22

simplest scientific explanation

Question 23

phylogeny

Answer 23

evolutionary history and relatedness of a group of organisms

Question 24

polytomy(pitchfork)

Answer 24

( uncertainty of who came first in phylogeny trees)
a section of a phylogeny in which the evolutionary relationship cannot be fully resolved to dichotomies

Question 25

reversal

Answer 25

process by where a character or trait that was lost in a common ancestor later regained by descendants

Question 26

sister taxa

Answer 26

pairs of terminal taxa and or clare’s that branch from a common node

Question 27

taxon

Answer 27

a named taxonomic group at any rank such