However, we can also think about this in a different way. Vertebrates have complex bodies, which they acquire through development. This is a main focus of this course, and we hope that you will write a final term paper focusing on this question. This is a really new field in science, and is currently one of the hottest areas of study. They have large, complex genomes.
Large genomes have large numbers of genes, which provide for complex bodies.
Moreover, we observe that the vertebrate genome contains many related copies of the same gene. The genome duplication hypothesis. They may have been in part responsible for the increase in vertebrate complexity during evolution. Later still, a third gene duplication event occurs and we get sperm with the haploid number of 16. But remember, we no longer buy the ladder icon.