In the case of the dorsal fin of a salmon and the dorsal fin observable in a dolphin, these structures are analogous of one another since they did not evolve directly from the same common …show more content…
It is easy to assume since the Mammalia family have homologous structures with corresponding bone patterns to the dolphin’s flippers. Therefore, this structure is a suitable representation of the common ancestry of all these organisms (mammals).Thus, the flippers of the dolphins and the pectoral fins of the salmon (a fish) are inherited from a predecessor organism common to both- mammals and fish- in their phylogenetic tree. Hence, these patterns may have evolved from the same structure, so these are likely to be homologous to one …show more content…
I mean, these two organisms come from different phyla. They may have originated from a common ancestor, but they are not specifically similar as a result of that ancestral antecessor. Instead, these two structures evolved similarities in response to natural selection, not as an inherited trait of the same organism. For example, the structures of the jointed legs in the insects and the birds may have originated with a different purpose given their different skeletal patterns. This assumption led me to believe that their process of convergent evolution occurred somehow later on, not as an original ancestral trait (here a phylogenetic tree would become truly