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Phylogenetic inertia or phylogenetic constraint refers to the limitations on the future evolutionary pathways that have been imposed by previous adaptations. [ 1 ] Charles Darwin first recognized this phenomenon, though the term was later coined by Huber in 1939. [ 2 ]
Phylogenetic bracketing is a method of inference used in biological sciences. It is used to infer the likelihood of unknown traits in organisms based on their position in a phylogenetic tree. One of the main applications of phylogenetic bracketing is on extinct organisms, known only from fossils, going back to the last universal common ancestor ...
The component programs of phylip use several different formats, all of which are relatively simple. Programs for the analysis of DNA sequence alignments, protein sequence alignments, or discrete characters (e.g., morphological data) can accept those data in sequential or interleaved format, as shown below.
Biological constraints are factors which make populations resistant to evolutionary change. One proposed definition of constraint is "A property of a trait that, although possibly adaptive in the environment in which it originally evolved, acts to place limits on the production of new phenotypic variants."
Phylogenetic comparative methods (PCMs) use information on the historical relationships of lineages (phylogenies) to test evolutionary hypotheses.The comparative method has a long history in evolutionary biology; indeed, Charles Darwin used differences and similarities between species as a major source of evidence in The Origin of Species.
The principle of phylogenetic reconciliation was introduced in 1979 [14] to account for differences between genes and species-level phylogenies. In a parsimonious setting, two evolutionary events, gene duplication and gene loss were invoked to explain the discrepancies between a gene tree and a species tree.
A phylogenetic tree, phylogeny or evolutionary tree is a graphical representation which shows the evolutionary history between a set of species or taxa during a specific time. [ 1 ] [ 2 ] In other words, it is a branching diagram or a tree showing the evolutionary relationships among various biological species or other entities based upon ...
Evolutionary progress as a tree of life. Ernst Haeckel, 1866 Lamarck's two-factor theory involves 1) a complexifying force that drives animal body plans towards higher levels (orthogenesis) creating a ladder of phyla, and 2) an adaptive force that causes animals with a given body plan to adapt to circumstances (use and disuse, inheritance of acquired characteristics), creating a diversity of ...