Question: Who argued in 2003 that all clades are by definition monophyletic groups?
Answer: Rachel Caspari (2003) have argued that clades are by definition monophyletic groups (a taxon that includes all descendants of a given ancestor) and since no groups currently regarded as races are monophyletic, none of those groups can be clades.
A single-select problem: Is the question answered in a satisfactory fashion?

Choices: [+] yes; [+] no;
yes