page_title: Character evolution
hierarchical_section_title: Character evolution
caption_attribution_description: English: A phylogenetic tree of living things, based on RNA data and proposed by Carl Woese, showing the separation of bacteria, archaea, and eukaryotes. Trees constructed with other genes are generally similar, although they may place some early-branching groups very differently, thanks to long branch attraction. The exact relationships of the three domains are still being debated, as is the position of the root of the tree. It has also been suggested that due to lateral gene transfer, a tree may not be the best representation of the genetic relationships of all organisms. For instance some genetic evidence suggests that eukaryotes evolved from the union of some bacteria and archaea (one becoming an organelle and the other the main cell). Français&#160;: Arbre phylogénétique hypothétique de tous les organismes vivants. L'arbre est basé sur des séquences de l'ARNr 16S. À l'origine proposé par Carl Woese, il montre l'histoire évolutive des trois domaines du vivant (bactéries, archaea et eucaryotes). Italiano: Albero filogenetico dei viventi. Basato sulle sequenze di Rna 16s, è stato originariamente proposto da Carl Woese e mostra la divisione dei tre domini degli organismi: Archea, Bacteria e Eukarya. Alberi costruiti su altre sequenze geniche sono generalmente molto simili, nonostante possano riposizionare differentemente alcuni dei gruppi più antichi. L'esatta relazione fra i tre domini è ancora oggetto di dibattito, così come la posizione della radice dell'albero. è stato inoltre suggerito che a causa dei trasferimenti laterali dei geni, un albero potrebbe non essere la migliore rappresentazione delle relazioni di tutti gli organismi. Per esempio alcune prove genetiche portano a credere che gli eucarioti si sarebbero evoluti dall'unione fra alcuni batteri e archibatteri (endosimbiosi). 中文: 这是一棵基于RNA资料的和由卡尔·霍斯提出的生命系统发生树。这棵发生树分为三个分支：细菌、古菌和真核生物。虽然由其他基因构成的发生树对于早期分支的分类很不相同，但是由于长分枝吸引，使得他们大体上是相同的。按照树根现在的位置，三域的确切关系还在辩论当中。曾经有人建议，因为横向基因转移，一棵发生树未必能最好体现所有生物体的基因关系。例如，有些遗传学的证据表明，真核细胞是进化自一些细菌和古菌（一种作为细胞器，另一种作为细胞主体）的结合体。
context_page_description: Character evolution is the process by which a character or trait evolves along the branches of an evolutionary tree. Character evolution usually refers to single changes within a lineage that make this lineage unique from others. These changes are called character state changes and they are often used in the study of evolution to provide a record of common ancestry. Character state changes can be phenotypic changes, nucleotide substitutions, or amino acid substitutions. These small changes in a species can be identifying features of when exactly a new lineage diverged from an old one.
context_section_description: Character evolution is the process by which a character or trait (a certain body part or property of an organism) evolves along the branches of an evolutionary tree. Character evolution usually refers to single changes within a lineage that make this lineage unique from others. These changes are called character state changes and they are often used in the study of evolution to provide a record of common ancestry. Character state changes can be phenotypic changes, nucleotide substitutions, or amino acid substitutions. These small changes in a species can be identifying features of when exactly a new lineage diverged from an old one.
caption: A phylogenetic tree
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