Final answer:
Linnaeus based his classification on physical similarities due to the lack of understanding of evolution and genetic similarities during his time.
Explanation:
Linnaeus based his system of classification primarily on physical similarities because during his time, the concept of evolution and the understanding of genetic and molecular similarities were not developed yet. With the advent of phylogenetic classification after Darwin's theory of evolution, biologists now prioritize evolutionary relationships over mere physical traits in grouping organisms.
Learn more about system of classification here:
https://brainly.com/question/606324
