Q
    / \
fish   Q  
      / \ 
   cat   Q
        / \ 
     dog   Q    
          / \
       cow   Q   
            / \ 
       horse   Q
              / \
         sheep   Q 
                / \ 
            wolf   Q  
                  / \ 
              frog   Q  
                    / \
           wolverine   Q
                      / \
                  seal   Q
                        / \ 
                  badger   Q
                          / \
                    walrus   Q
                            / \
                      ocelot   Q
                              / \ 
                       hamster   Q
                                / \ 
                          gerbil   Q
                                  / \
                          platypus   Q
                                    / \
                             unicorn   Q
                                      / \ 
                               pegasus   axolotl