Final answer:
Morphological data can be influenced by convergent evolution and doesn't always reflect genetic relatedness, leading to erroneous evolutionary relationships. Genetic and molecular analyses are now used in addition to morphological data to provide a more accurate understanding of evolutionary relationships.
Step-by-step explanation:
Morphological data alone might lead scientists to group animals into erroneous evolutionary relationships because morphological data can be influenced by convergent evolution and doesn't always reflect genetic relatedness. Morphological characteristics, such as body shape and color, may evolve independently multiple times throughout evolutionary history, leading to similar appearances in unrelated animals. This is why genetic and molecular analyses are now used in addition to morphological data in modern phylogenetics to provide a more accurate understanding of evolutionary relationships.