Phylogenetics and Systematics by Helen Harmel https://padlet.com/helenharmel/26tc0qd77djh yay for Final Exam Review en-us 2016-12-13 00:54:36 UTC 2016-12-13 12:49:06 UTC hello@padlet.com PHYLOGENY helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143268767  Phylogeny is the evolutionary history of a species or group of species ]]> 2016-12-13 01:57:01 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143268767 SYTEMATICS helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143268798  a discipline focused on classifying organisms and determining their evolutionary relationships. ]]> 2016-12-13 01:57:43 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143268798 PARTS OF A PHYLOGENETIC TREE helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143268850
  • Taxonomy is an ordered division of organisms into categories based on a set of characteristics used to assess similarities and differences. 
  • Systematists use data ranging from fossils to molecules and genes to infer evolutionary relationships. 
  • Each branch point (node) represents the divergence of two species.  
  • Sister taxa are groups that share an immediate common ancestor 
  •  Homology is similarity due to shared ancestry 
  •  Analogy is similarity due to convergent evolution  
    • ]]>     2016-12-13 01:58:50 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143268850     PHYLOGENTIC TREES helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143268868
  • Phylogenetic trees graphically model evolutionary history and can represent both acquired traits and those lost during evolution.  
  •  Phylogenetic trees and cladograms illustrate speciation that has occurred, in that relatedness of any two groups on the tree is shown by how recently two groups had a common ancestor. 
  •  Phylogenetic trees and cladograms can be constructed from morphological similarities of living or fossil species, and from DNA and protein sequence similarities.
    • ]]>     2016-12-13 01:59:11 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143268868     THEIR SIGNIFICANCE helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143269443
  •  The best hypotheses for phylogenetic trees fit the most data: morphological, molecular, and fossil record evidence.
  • They identify homology
  •  They distinguish groups, families, and taxonomies of species.
  • They show when traits were lost or acquired through evolution.
  • Shows which traits were selected during natural selection to show which adaptations were most successful.
    • ]]>     2016-12-13 02:12:39 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143269443     helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143269785 2016-12-13 02:19:32 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143269785 EXAMPLE BREAKDOWN helenharmel https://padlet.com/helenharmel/26tc0qd77djh/wish/143269831
  • They all originated from a common ancestor, and all are vertebrates.
  • The shark is closest to the common ancestor.
  • A bony skeleton formed after the shark.
  • Four limbs formed after the ray-finned fish, and gills/water animals were still the similar species.
  • Then it switched to land-water species for the amphibians.
  • The amniotic egg trait formed after the amphibians,
  • For primates and rodents/rabbits, hair specifically formed for just those species.
  • Then it goes back to land-water species for the crocodiles who have the pre-orbital tenestra.
  • Lastly, the dinosaurs and birds are the latest to evolve for this tree as they contain all the traits except for hair which is specific to the primates and rodents/rabbits.
  • Primates & Rodents/rabbits would be sister taxa as they branch off similarly from a connected common ancestor.
    • ]]>     2016-12-13 02:20:17 UTC https://padlet.com/helenharmel/26tc0qd77djh/wish/143269831