======Build a Phylogenetic Tree======


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**Alternative titles:** Constructing a Cladogram
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====Summary====                   
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====Procedure====  
  *See links for suggested methods and activities.



====Links==== 
Cladistics Part 1: Constructing Cladograms - Professor Dave Explains: 
{{youtube>CPcNfQfjjiw?}}\\

AP Biology - Cladogram Practice with Minions - MrGrodskiChemistry: 
{{youtube>9_QAyTk7WrA?}}\\

📄 Constructing a Cladogram - Science Corner: [[http://biologycorner.com/worksheets/cladogram_construction.html]]\\


====Variations====
 * Use fossil ages to constrain branching order, showing how time influences cladogram construction.  
  * Incorporate molecular data (DNA sequences) alongside morphological data for comparison.  
  * Provide a mixed set of traits with some convergent or lost features to challenge students to think critically.  
  * Ask students to create their own imaginary organisms with defined traits, then trade and construct cladograms with classmates’ sets.




====Safety Precautions====
  * If building physical trees with pins, scissors, or wire, supervise tool use and keep work surfaces clear.



====Questions to Consider====
  * What features are shared derived traits (synapomorphies), and how do they define clades?  
  * Which traits are unique (automorphies), and how do they help identify individual species but not broader groups?  
  * How does including an outgroup help identify ancestral versus derived traits?  
  * Could different interpretations of the data lead to different cladograms? How might scientists resolve disagreements?  
  * How does constructing cladograms help us understand evolutionary relationships and common ancestry?