Table 2. Molecular clock model output.

Molecular clock	Population model prior	AICM++	Mean substitution rate (95% HPD)	TMRCA Grenadian strains*	Substitute rate Grenadian branch
Strict	Bayesian skyline	28430	3.26×10−4 (2.49–4.04×10−4)	16.4 yrs ago (8.6–25.1)	3.26×10−4 (2.49–4.04×10−4)
Strict	Constant	28440	2.78×10−4 (1.96–3.57×10−4)	23.4 yrs ago (14.6–34.8)	2.78×10−4 (1.96–3.57×10−4)
Uncorrelated lognormal	Bayesian skyline	28360	3.99×10−4 (2.88–5.15×10−4)	11.6 yrs ago (5.5–23.0)	5.09×10−4 (2.99–7.40×10−4)
Uncorrelated lognormal	Constant	28370	3.17×10−4 (2.01–4.33×10−4)	22.7 yrs ago (12.6–37.8)	4.36×10−4 (2.38–6.94×10−4)

* years since most recent strains (2013),

⁺⁺AICM is an analogue of Akaike's information criterion estimated through Markov Chain Monte Carlo simulation using the method-of-moments estimator [33]. Lower values indicate better model fit.