Bio1151b Chapter 24 The Origin of Species
  1. Evolutionary change of a species over time is called             , while in               a parent species may branch off to yield multiple species.
  2. A             species is a group of organisms whose members can interbreed in nature and produce          offspring.
  3. Reproductive           can prevent interbreeding and result in reproductive            .
    • Prezygotic barriers prevent the formation of          , and include          ,           ,             ,             , and          isolation.
    • Postzygotic barriers prevent the         from developing into a fertile adult, and include reduced hybrid            , reduced hybrid            , and hybrid            .
  4. Speciation can occur by             (“Other Country”) speciation, or by            speciation.
    • In             speciation, geographic separation can reduce       flow and result in reproductive            where the isolated subpopulations can evolve separately.
    • In            speciation, geographically overlapping populations can evolve into separate species due to habitat                  .
  5. Adaptive            can produce many species, adapted to different         , from a common ancestor which was introduced to a new environment, such as the Hawaiian archipelago.
  6. The decline and             of some species often provides opportunities for other species to occupy the           and         that open up.
Bio1151b Chapter 25 Phylogeny and Systematics
  1.            is the evolutionary history of species.              is the relationships of organisms, based on shared          characters inherited from a common           .
  2. Some of the tools biologists use include the         record, as well as                and            comparisons to infer evolutionary relationships.
    • Most of the         record is found in layers of              rock called         .
    •                similarity can be misleading due to             evolution ( analogy ).
    •            homologies that make use of computer programs to analyze      segments can reveal many relationships not attainable by other methods.
  3. Carolus Linnaeus introduced a system, called           , for classifying species in seven hierarchical categories (taxa).
  4. The scientific name of an organism uses           nomenclature composed of its        and           epithet, such as Panthera pardus and Homo sapiens.
  5. Phylogenetic relationships are shown as branching trees where each branch point represents the             of two       when they shared a common           .
  6. Shared ancestry and shared          characters are drawn on a            to show evolutionary relationships; this practice is called             .
  7. A clade must be               , and consists of the           species and all its descendants.
  8. A            depicts the chronology of divergences by having the         of a branch reflect the number of changes that have taken place in a particular      sequence in that lineage.
  9. The tree of life is divided into three great clades called          :           (Monera),          , and          .