Cladistics: Monophyletic, Paraphyletic, and Polyphyletic Groups - Review

Cladistics (분기학) (a) Monophyletic group (clade) A B Group I (b) Paraphyletic group (c) Polyphyletic group A A B B Group III C C C D D D E E F F G G Group I, consisting of three species (A, B, C) and their common ancestor , is a monophyletic group (clade), meaning that it cons...

Cladistics (분기학) (a) Monophyletic group (clade) A B Group I (b) Paraphyletic group (c) Polyphyletic group A A B B Group III C C C D D D E E F F G G Group I, consisting of three species (A, B, C) and their common ancestor , is a monophyletic group (clade), meaning that it consists of an ancestral species and all of its descendants. 세 종(A, B, C)으로 구성된 그룹 I은 그리고 그들의 공통 조상(1), 단일 계통이다 즉 단계통은 조상 종과 그 모든 후손으로 구성됨을 의미한다 Group II Group II is paraphyletic, meaning that it consists of an ancestral species and some of its descendants (species D, E, F) but not all of them (does not include species G). 그룹 II는 측계통으로, 즉 조상 종 그 후손 (종 D, E, F)으로 구성되지만 전부는 아니다 (종 G는 포함되지 않음). E F G Group III, consisting of four species (A, B, C, D), is polyphyletic, meaning that the most recent common ancestor of its members is not part of the group. 4종(A, B, C,D)는 다계로, 가장 최근의 공통 조상은 어떤 구성원들의 가장 최근 공통 조상과 한 그룹에 속하지 않는다 Figure 20.10 Monophyletic, paraphyletic, and polyphyletic groups (단계통, 측계통, 다계 군) Copyright © 2021 Pearson Education Ltd. All Rights Reserved Figure 20.11 Paraphyletic Versus Polyphyletic Groups (측계통 군 vs 다계 군) 이 집단은 공통조상의 모든 자손을 포함하지 않기 때문에 측계통이다 This group is paraphyletic because it does not include all the descendants of the common ancestor (it excludes cetaceans). Common ancestor of even-toed ungulates Other even-toed ungulates Hippopotamuses Cetaceans Seals Bears Other carnivores This group is polyphyletic because it does not include the most recent common ancestor of its members. Copyright © 공통조상을 2021 Pearson Education Ltd. All다계통이다 Rights Reserved 이 집단은 구성원 종들의 가장 최근의 포함하지 않으므로 Shared Ancestral and Shared Derived Characters (공유조상형질과 공유파생형질) • Organisms have some characters that are shared with their ancestors and some characters that differ (유기체에는 조상과 공유하는 특성과 다른 특성이 있다) • A shared ancestral character (공유조상형질) is a character that originated in an ancestor of the taxon (공유 조상형질은 분류군의 조상에서 유래한 형질이다) • A shared derived character (공유파생형질) is an evolutionary novelty unique to a particular clade (공유 파생형질은 파생된 고유한 진화이다) • A character can be both ancestral and derived, depending on the context (상황에 따라 공유조상형질 일수도, 공유 파생형질일수도 있다) – For example, when considering the entire animal kingdom, the backbone is a shared derived character because it is present only in vertebrates (예를 들어, 동물계 전체를 고려할 때 등뼈는 척추동물에만 존재하기 때문에 공유파생형질이다) – When considering only the group including mammals, the backbone is an ancestral character because it is present in mammals and all other vertebrates (포유류를 포함한 그룹만 고려할 때, 등뼈는 포유류와 다른 모든 척추동물에 존재하기 때문에 공유조상형질이다) Copyright © 2021 Pearson Education Ltd. All Rights Reserved Inferring Phylogenies Using Derived Characters (파생형질을 이용하여 계통발생 유추하기) • Determining the clade in which shared derived characters first appeared can help to infer evolutionary relationships (공유파생형질이 처음 등장한 분기를 파악하면 진화 관계를 추론하는 데 도움이 될 수 있다) • An ingroup (내부군) is the group of species being studied • An outgroup (외부군) is a species or group of species closely related to but not part of the ingroup 창고기 칠성장어 양막 Copyright © 2021 Pearson Education Ltd. All Rights Reserved Figure 20.12 Using derived characters to infer phylogeny (파생형질로 계통수 추론하기) Figure 20.14 Branch Lengths Can Indicate Time (가지의 길이는 시간을 나타낼 수 있다) Drosophila Lancelet 창고기 Zebrafish Frog Chicken Human Mouse 500 400 300 200 100 Present Millions of years ago Copyright © 2021 Pearson Education Ltd. All Rights Reserved