Is it spectacular startling performance of great agility, or chromosomal chaos ? Aneuploidy (abnormal number of chromosomes) was proposed to be the cause of cancer (Figure 65). However, the causes of aneuploidy remained unexplained. It has been recognized that the changing chromosomal numbers and genetic changes within, may encode a phenotype drastically different from what was pre-expressed by the pre-transformed cell. Some of the cells encoded by aneuploid chromosomal sets may appear as if derived from a species different from the pre-aneuploid host. Thus carcinogenesis may be viewed as a form of speciation (trans-speciation). Misdistribution of chromosomes into daughter cells at mitosis results in aneuploidy. Aneuploidy is connected with oncogenesis as a form of “speciation” as elaborated on by Duesberg et al .