Darwinian Evolution
Charles Darwin's phrase for evolution, emphasizing that all organisms are related through an ancestor from the past
What is descent with modification?
These represent the remains or traces of organisms from the past, often found in sedimentary rock.
What are fossils?
This term refers to the aggregate of all copies of every type of allele at all loci in every individual in a population.
What is gene pool?
The existence of biological factors or barriers that impede members of two species from interbreeding
What is reproductive isolation?
A branching diagram used to represent a hypothesis about the evolutionary history of a group of organisms
What is a phylogentetic tree or cladogram?
This term describes species that are found in one specific geographic location and nowhere else in the world
What is endemic?
Anatomical resemblances that represent variations on a structural theme present in a common ancestor.
Homologous structures
This specific effect occurs when a few individuals become isolated from a larger population and establish a new population with a different gene pool.
What is the founder effect?
The existence of biological factors or barriers that impede members of two species from interbreeding
What is allopatric speciation?
Groups of organisms that share an immediate common ancestor and are each other's closest relatives on a tree.
What is a Sister Taxa?
This process occurs when individuals with certain inherited traits tend to survive and reproduce at higher rates than others because of those traits
What is natural selection?
Remnants of features that served a function in the organism’s ancestors but no longer serve a clear purpose.
What are vestigial structures>
This equation is used to test whether a population is evolving or is in a state of equilibrium.
What is Hardy-Weinberg Equilbrium?
A pre-zygotic barrier where species breed at different times of the day, different seasons, or different years.
What is temporal isolation?
A group on a phylogenetic tree that includes an ancestral species and all of its descendants
What is a clade?
While natural selection leads to adaptation, this is the specific reason why it cannot fashion "perfect" organisms.
What is selection can only act on existing variations
This type of evolution occurs when two distantly related groups independently evolve similar features, such as analogous structures.
What is convergent evolution?
A type of selection that favors individuals at both extremes of a phenotypic range rather than intermediate phenotypes.
What is disruptive selection?
This post-zygotic barrier occurs when the first-generation hybrids are fertile, but their offspring are feeble or sterile
What is hybrid breakdown?
An evolutionary novelty or character that is unique to a particular clade.
What is a shared derived character?
These are the specific conditions or "necessities" that must be present within a population for natural selection to occur
What is genetic variation, overproduction of offspring and competition?
This field of study compares the early stages of animal development to reveal homologies not visible in adult organisms.
What is comparitive embryology?
These are the two primary sources of genetic variation that make evolution possible within a population.Explain these two.
What is mutation and sexual selection?
This evolutionary model describes long periods of apparent stasis interrupted by brief periods of sudden change.
What is puncuated equilibrium?
On a phylogenetic tree, this feature represents the divergence of two evolutionary lineages from a common ancestor
What is a node?