how vertebrates have evolved over the years

Lancelets present a unique case study when investigating how vertebrates have evolved over the years. Lancelets ceased being part of the vertebrate family over five hundred million years ago (Romer and Parsons 39). Nevertheless, the organism’s genomes still have traces of the vertebrates. For instance, lancelets’ gene composition indicates that the organisms have appropriated old genomes through new functions. The first describable organism in the evolutionary phylogeny of lancelets is the ‘Branchiostoma Lanceolatum’, a molluscan slug of the Limax species. In the early 1800s, scientists “brought the phylogenetic position of the group closer to the agnathan vertebrates (including hagfish and lampreys), including it in the new genus Branchiostoma ” (Putnam 1068). The classification of the organism was mainly dependent on the organism having gills and a mouth. The organism was later categorized in the Amphioxus genus. The lancelets’ are closely related to vertebrates, notochord data, and urochordata. Currently, lancelets indicate a close relationship with more than 30 other species.