Chapter 27- Phylogenies And The History Of Life Flashcards
Phylogenetic Tree
A diagram of the ancestor-descendant relationships among populations or species.
Phylogeny
The evolutionary history of a group of organisms.
Branch
Represents a population through time.
Nodes/Fork
Represents the point in time when an ancestral species split into two or more descendant species.
Tip/Terminal Node
Represents a group living today or that ended in extinction.
Phenetic Approach
Estimates trees based on computing a statistic that summarizes the overall similiarity among populations.
Cladistic Approach
Infers trees based on the realizations n that relationships among species can be reconstructed by indentifying shared derived characters.
Ancestral Trait
A characteristic that existed in an ancestor.
Derived Trait
A trait that is a modified form of the ancestral trait.
Homology
When traits are similar due to shared ancestry.
Homoplasy
When traits are similar for reasons other than common ancestry.
Convergent Evolution
When natural selection favors similar solutions to the problems posed by a similar way of making a living.
Parsimony
The most likely explanation or pattern is the one that implies the least amount of change.
SINE(Short Interspersed Nuclear Element)
Parasitic gene sequences that occasionally insert themselves into the genomes of mammals.
Fossil
A piece of physical evidence from an organism that lived in the past.
Fossil Record
The total collection of fossils that have been found throughout the world.
Paleontologists
Scientists who study fossils.
Precambrian Interval
The interval in between the creation of the Earth and the appearance of most animal groups.
Cast
A mold of the remains of an organism.
Paleozoic Era
The era in which animals, land plants, and fungi were created and diversified.
Mesozoic Era
Began with the end-Permian extinction events and ended with the extinction of the dinosaurs.
Cenozoic
Era divided into the Paleogene period and Neogene period. Includes today’s events.