Animal models and conserved processes

Table 4 Causal analogical models

X, the model	Y, the system being modeled	Shared properties between X and Y	Perturbation to the model	Outcome in model	Outcome in system being modeled
Animal system (for example, Pan troglodytes)	Human system
		a. Genes. >90% of nucleotide sequences identical.	Exposure to HIV.	State S1. Mild illness of limited duration.	AIDS. State S1 is not shared despite the presence of shared, relevant properties.
		b. Immune system. Many commonalities. Constructed on generally the same plan.
		c. White blood cells present and function similarly.
		d. Receptors on white blood cells also present and function similarly.
		e. Shared intracellular components of white blood cells.

Shared properties a . . . e for humans and chimpanzee do not result in state S1 also being shared.

ISSN: 1742-4682