Phylogenetics

Question 1

What is descent with modification?

Answer 1

All species, living and extinct, had descended without interruption, from one or a few original forms of life

Question 2

What is something that all life on Earth shares?

Answer 2

a common ancestor (descent with modification = diversity today)

Question 3

What are the 8 (or 9) taxons?

Answer 3

(Life)
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 4

Who is the father of modern taxonomy and systematics?

Answer 4

Carolus Linnaeus

Question 5

What is binomial nomenclature?

Answer 5

every organism is given a 2-part Latine name 1) a generic name (=genus, which is capitalised) and 2) a specific name (=species which is lower case)
e.g. Homo sapiens (Humans)

Question 6

What is a genus?

Answer 6

A group of one or more species related by common descent from a recent ancestor and sharing similar traits

Question 7

What is a species?

Answer 7

a group within a genus whose members share the same set of structural traits and can successfully interbreed with one another to produce fertile offspring

Question 8

What is hierarchical classification?

Answer 8

a filing system for grouping species into a hierarchy of general categories. (nested pattern of similarities among species)

Question 9

What is a polymorphic species?

Answer 9

the occurrence of two or more different forms of individuals of the same species

Question 10

What is a cryptic species?

Answer 10

two or more morphologically identical species

Question 11

What is the biological species concept?

Answer 11

organisms are members of the same species if they can mate with each other when they encounter each other in nature and produce fertile, viable hybrids

Question 12

What are systematics?

Answer 12

field of biology that recpnstructs the evolutionary history (pyllogeny) and studies the patterns of relationships among organisms (taxa): visualised as evolutionary trees

Question 13

What are phylogenetic trees?

Answer 13

genealogies for organisms
is a hypothesis regarding the evolutionary history for a group of organisms

Question 14

how is closeness of relationships determined in a phylogenetic tree?

Answer 14

by looking to see how recently two groups shares a common ancestor

Question 15

in phylogenetic trees, what is the order of branches (nodes) mean?

Answer 15

the sequence of events in time

Question 16

on a phylogenetic tree what are sister groups?

Answer 16

groups more closely related to one another than any other group

Question 17

what are clades?

Answer 17

a group of organisms that represent a common ancestor and all the descendants of the ancestor

Question 18

what is a taxon?

Answer 18

a group of organisms that is given a name, which ideally share a common ancestor

Question 19

what are natural taxa?

Answer 19

when clades (monophyletic groups) and taxa are consistent with common ancestry

Question 20

what is a monophyletic group?

Answer 20

taxa that encompass an ancestor and all its descendants (also called a clade), members bound together by common ancestry not shared wuith other taxa

Question 21

What is a paraphyletic group?

Answer 21

a taxon that includes an ancestor, but not all of the descendants of that ancestor (artificial taxa)

Question 22

What is a polyphyletic group?

Answer 22

a taxon that has at least two separate evolutionary origins from unrelated ancestors

Question 23

What is homology?

Answer 23

likeness among groups of organisms due to shared ancestry

Question 24

What is convergent evolution?

Answer 24

species from different evolutionary linmeages may come to resemble one another if they have similar ecological roles and natural selection generates analogous adaptation (homoplasy)

Question 25

what are plesiomorphic (or ancestral) characters?

Answer 25

characteristics shared by all members of the group including the most recent common ancestor

Question 26

What are apomorphic (or derived) characters?

Answer 26

Homologous characters that have evolved more recently 9after divergence from the common ancestor) and therefore only occur among certain taxa when building a phylogeny

Question 27

What is an Ingroup taxa?

Answer 27

any group of theoretically related organisms

Question 28

What is an Outgroup taxa?

Answer 28

a group or taxon used for comparative purposees in a phylogenetic analysis: related to the ingroup but presumed to have diverged before the ingroup diversifies

Question 29

what is parsimony?

Answer 29

the most plausible explanation of an occurrence or phenomenon is often the simplest, involving the fewest assumptions or evolutionary changes