The process of evolution drives the diversity and unity of life.
Enduring Understanding 1.A. Change in the genetic makeup of a population over time is evolution
1.A.1: Natural selection is a major mechanism of evolution
1.A.2: Natural selection acts on phenotypic variations in populations
1.A.3: Evolutionary change is also driven by random processes
1.A.4: Biological evolution is supported by scientific evidence from many disciplines, including mathematics
Enduring Understanding 1.B: Organisms are linked by lines of descent from common ancestry
1.B.1: Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today
1.B.2: Phylogenetic trees and cladograms are graphical representations of evolutionary history that can be tested.
Enduring Understanding 1.C: Life continues to evolve within a changing environment
1.C.1: Speciation and extinction have occurred throughout the Earth’s history
1.C.2: Speciation may occur when two populations become reproductively isolated from each other
1.C.3: Populations of organisms continue to evolve
Enduring Understanding 1.D: The origin of living systems is explained by natural processes
1.D.1: There are several hypotheses about the natural origin of life on earth, each with supporting evidence
1.D.2: Scientific evidence from many different disciplines supports models of the origin of life