taxonomy

• Genet


  To do with sexual reproduction
• Ramet


  To do with asexual reproduction
• Nomenclature


  Giving names to organisms
• Systematics


  Establishes relationships amongst groups.

  Puts diversity into context, and monitors changes in groups over time
• Taxonomy


  -Making groups of organisms based on similarities.

  Broader groups with fewer similarities and narrower groups with more similarities
• Taxon


  Unit of taxonomy; a group of organisms without rank
• Rank


  -Indicator of the broadness of the group; a name indicating how specific is a taxon.

  -The relative position of a group containing one organism amongst all the groups that contain that organism
• Phylogeny


  -Evolutionary history of species.

  -Works together with taxonomy
• Rules for nomenclature


  - scientific name

  -the name has to be unique

  -name cannot be misleading

  -Name has to use Latin alphabet

  -Name has to follow agreed-upon rules
• Homology


  The existence of shared ancestry between a pair of structures, or genes, in different taxa

  (Divergent evolution)

  
• Homoplasy


  Existence of similar structures that do not come from a common ancestor.

  (convergent evolution)

  
• clades


  Groups of organisms sharing common traits and a common ancestor
• Synapomorphy


  The traits shared by a clade
• Monophyletic


  Common ancestor and no external branch

  
• Paraphyletic


  Common ancestor but with external branches

  
• polyphyletic


  No single common ancestor

  
• species

  A reproductive community of populations (reproductively isolated from the rest, that occupies a specific niche in nature.
• Phylogenetic concept of species

  -Pure monophyletic groups

  -avoids referring to evolution, focuses on phylogenetic changes

  -only similar organisms
• Species


  The smallest group of organisms sharing ancestors and descendants which can be differentiated from other groups
• Reproductive community


  (Problem: Only for organisms with sexual reproduction)
• Biological concept of a species


  • A species is a reproductive community of populations (reproductively isolated from the rest) which occupies a specific niche in nature
  • Reproductive state determined by chromosomal and biochemical traits
  • Direct test: check if they produce fertile offspring (not always feasible)
• Problems with defining species


  • A species has its time and space contexts and trying to explore beyond these context, in the limit between two species is a problem (eg. Fossils)
• Evolutionary concept of a species


  • Overcomes the asexual reproduction problem by omitting all reference to reproduction , assuming it in the evolutionary history
  • A single lineage of ancestor-descendant populations of organisms which maintains its identity from other such lineages [in space and time] and which has its own evolutionary tendencies and historical fate
• Phylogenetic concept of a species


  • A species is an irreducible (basal) cluster of organisms, diagnosable distinct from other such clusters, and within which there is a parental pattern of ancestry and descent
  • Monophyletic groups , avoids referring to evolution and focuses on phylogenetic changes , only similar organisms can be considered species
• First classifications of life


  • Unable to move , with chlorophyll and roots: plants
  • Able to move and capture their own food: Animals
  • Bacteria randomly distributed
• 6 kingdoms of life


  • Animalia
  • Fungi
  • Plantae
  • Protista
  • Archaea
  • Bacteria
• Archaea and Bacteria


  • Unicellular
  • Cell wall
  • No nucleus or organelles
  • Autotrophs or heterotrophs
  • Small
  • Locomotion or not
• Protista


  • Unicellular
  • Locomotion (cilia , flagella , ameboid)
  • No cell wall
  • Nucleus and organelles
  • Autotrophs or heterotrophs
• Diversity


  • Variability among living organisms
  • Response to a need in one of the three main functions
  • Normally associated with morphological traits
  • Sometimes regarding functions and roles in ecosystem
  • Form follows function
• To study diversity, we will study the form of organisms, in association with its function (focusing on reproductive function)