Institutional review boards (IRBs) have the responsibility to ensure the protection of human-research subjects and are legally liable if they fail to do so.
Though body size can be altered with environmental or behavioral changes, anatomic shape, which appears to be genetically determined, cannot be changed except by surgery, trauma, or illness.
Specific contributions to a scientific article entitle the contributor to be included as an author; requests for authorship by those who have not made those specific contributions are unethical.