Sys Zoo Quiz 2

• Micro taxonomy


  The science of formally defining and naming species and their subcategories, and of assigning entities to species and their subcategories
• Species


  The basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity
• Speciation


  The evolutionary process by which populations evolve to become distinct species
• Cladogenesis


  The splitting of lineages, as opposed to anagenesis, phyletic evolution within lineages
• Allopatric speciation


  Two populations of the same species become isolated from each other due to geographic changes
• Peripatric speciation


  1. Members on the periphery, or border, of a large population separate off from the main group and become a new species over time

  2. The new population enters a different biological niche

  3. The new population is usually small, causing genetic drift and changes in the frequency of genes
• Parapatric speciation


  1. Subpopulations of the same species are mostly isolated from each other, but have a narrow area where their ranges overlap

  2. Can occur between multiple subpopulations next to each other where all the populations next to each other can interbreed, but each subpopulation is so slightly different that the members on the extreme ends would not be able to interbreed with each other (ring species)
• Sympatric speciation


  1. New species emerge from populations living in highly overlapping or even identical areas

  2. More common in bacteria than multicellular organisms due to gene transfer
• Macro taxonomy


  The taxonomy of larger biological units (as family, order, class)
• Taxonomic characters


  • Morphological
  • Physiological
  • Molecular
  • Behavioral/Ethological
  • Ecological
  • Geographic
• Artificial system of classification

  Based on the morphological characters, non-evolutionary features of the organisms and not expressing the true natural relation species
• Natural system of classification

  Grouping organisms based on similarities first and then identifying shared characteristics, where all members of a particular group would have shared a common ancestor
• Phylogenetic classification system


  Based on the evolutionary ancestry, showing the genetic relationships among organisms, generating trees called cladograms
• Hierarchical Classification (Linnaean)


  A system of grouping things according to a hierarchy, or levels and orders, from kingdom down to species
• International Code of Zoological Nomenclature (1964)

  The system of rules and recommendations authorized by the International Congress of Zoology to promote stability and universality in the scientific names of animals and to ensure that each name is unique and distinct
• Salient features of the "Code"

  • Names must either be Latin or Latinized
  • Names of taxa higher than species should be uninominal
  • Name of a species is binomen
  • Name of a subspecies is a trinomen
  • Name of a subgenus is placed in parenthesis between genus and species
  • Family name should end in DAE
  • Genus name should be a noun in nominative singular or treated as such
  • Species name should be an adjective or noun in nominative singular agreeing in gender with the generic name, or a noun standing in apposition to the generic name
  • Zoological nomenclature is independent of other systems
  • All names given to the species from time to time should be mentioned in synoymy
  • Author's name is not part of the name
  • Law of priority: The valid name is the oldest name published and available
  • Synonymy: Synonyms are different names assigned to the same taxon
  • Homonymy: Homonyms are identical names in spelling for different species of the same genus and for different genera of a family
  • Holotype: Single specimen on which description of the species is based
  • Allotype: Specimen of the opposite sex to holotype
  • Paratype: All remaining specimens after the designation of holotype and allotype
  • Syntypes: All specimens that the author studied for the description of the species if no holotype is designated
  • Lectotype: One specimen from syntypes designated as Lectotype
  • Neotype: A specimen designated as the type if all type-specimens are destroyed
• Macrotaxonomy


  Classification of organisms above the species level
• Taxonomic character


  Any attribute of a member of a taxon by which it differs or may differ from a member of a different taxon
• Kinds of taxonomic characters

  • Morphological
  • Physiological
  • Ecological
  • Ethological
  • Geographical
• Morphological characters


  • General external structures (morphology)
  • Special structures like genitalia
  • Internal morphology of soft and hard parts
  • Larval stages and embryology
  • Karyology (chromosome structure)
• Physiological characters


  • Growth constants and temperature tolerance
  • Metabolic factors
  • Body secretions
  • Genic sterility factors
  • Serology (protein reactions)
• Ecological characters


  • Food preference, breeding season, tolerance to physiological factors, resistance to predators and competitors
  • Habitat and host specificity
  • Seasonal variations
  • Parasite-host reactions
• Ethological characters


  • Behaviour patterns used for species delimitation (e.g. mating sounds, webbing patterns)
• Geographical characters


  • General biogeographic patterns
  • Allopatric-sympatric relationships
• Classification


  A division or category in a system which divides things into groups or types
• Principles of classification


  • Homology
  • Parallelism
  • Convergence
  • Analogies
• Homology


  Anatomical features of different organisms that have similar appearance or function because they were inherited from a common ancestor
• Parallelism


  Independent acquisition of similarities in characters in organisms, found in closely related animals descended from a common ancestor
• Homology


  Anatomical features of different organisms that have similar appearance or function because they were inherited from a common ancestor that also had them
• The more homologies two organisms possess, the more likely it is that they have a close genetic relationship
• Parallelism


  Independent acquisition of similarities in characters in organisms, found in closely related animals that have descended from common ancestor, caused by parallel evolution
• Three Different Sources of Phylogenetic Parallelism


  • Similar genetic factors such as parallel mutations and gene recombinations
  • Parallel natural selection acting on homologous organs, leading to similar adaptations
  • Parallel selection acting on analogous organ due to identical environmental conditions, leading to superficial similarity of characters
• Convergence


  The process whereby not closely related (not monophyletic), independently evolve similar organisms traits as a result of having to adapt to similar environments or ecological niches
• Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups
• Analogies


  Anatomical features that have the same form or function in different species that have no known common ancestor
• Analogies


  • The wings of a bird and a butterfly
  • Penguins and fish both have fin-like structures
  • Many species of plants, fungi, and bacteria can have analogous traits based on their environmental demands and not their ancestral lineage
• Functions of Taxonomic Characters

  • They have a diagnostic aspect uniquely specifying a given taxon (used during an analytical phase to determine the units of classification)
  • Function as indicators of relationship (Synthetic phase of delimiting and ranking of higher taxa)
  • Key Characters - easily perceived, low variability, present in preserved materials
• Linnaean Hierarchy


  A system of classification of living organisms into progressively more inclusive groups based on similarities and differences, with the broadest groups being kingdoms, then phyla, then classes, orders, families, genera, and species
• Kingdoms in Linnaean Hierarchy

  • Prokaryotes
  • Protists
  • Fungi
  • Plants
  • Animals
• Phylum


  A taxonomic ranking that comes second in the Linnaean hierarchy of classification, after kingdom, where organisms in a phylum share a set of characteristics that distinguishes them from organisms in another phylum