Download Presentation - The PPT/PDF document "Phylogenetic Analysis – Part I" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Presentation on theme: "Phylogenetic Analysis – Part I"— Presentation transcript:
Phylogenetic Analysis – Part I
Phenetics (brief review)
Phylogenetics & Characters
Science of organismal diversity.
Discovery, description and interpretation of biological diversity.
Discovery and description of the evolutionary tree of life.
Synthesis of information in the form of predictive classification systems.
Production of identification tools (e.g., keys, floras and faunas, monographs, etc.)
Some important definitions
= the study of the biological diversity on Earth and its evolutionary history.
) = a group of organisms distinct enough to be distinguished by a name and ranked in a definite category.
= the delimitation, ordering and ranking of taxa.
= the theory and practice of classifying organisms.
= tribe, race
= refers to birth
= the study of the evolutionary relationships of organisms
= evolutionary relationships;
genealogical (through time)
Historically, systematists relied on similarities to classify organisms
Pheno = Greek for display, referring to visible characteristics
= method of classifying organisms based on overall similarity
Phenetic Classification Systems
Were originally designed to reflect God’s plan of creation [“natural order”]
Later systems were considered “natural” in that presumably related plants were grouped together.
Were based on many characters selected from experience, not from a pre-existing theory
Overall similarity was the main criterion; all characters had equal weight
Phenetics vs. Phylogenetics
A plant example:
Modern systematists seek an evolutionary interpretation for the relationships between organisms.
Simple “matching” or relationships based on superficial similarity may not reflect evolutionary relationships.
Testability and identification of specific characters used to group taxa is lacking in most phenetic methods.