Table 3.
Arion diversification tests using speciation and extinction rate-constant models and rate-variable linear diversity-dependent logistic (DDL), exponential diversity-dependent (DDX) and yule-2-rate.
| Package | Function | IST | Model | λ 0 or r 0 | μ 0 | Extra parameters | AIC | Δ AIC |
|---|---|---|---|---|---|---|---|---|
| Laser | fitdAICrc | no* | Pure-birth (λA) | 0.135 | ‡ | 30.666 | 7.525 | |
| Laser | fitdAICrc | no* | Birth-death (λ 0A, μ 0A) | 0.135 | 0.000 | 32.666 | 9.525 | |
| Laser | fitdAICrc | no* | DDL ( r 0 A, K A) | 1.579 | ‡ | K = 16.727 | 18.831 | 0.000 |
| Laser | fitdAICrc | no* | DDX (r 0A, xpA) | 0.584 | ‡ | xp = 1. 072 | 20.018 | 4.770 |
| Laser | fitdAICrc | no* | yule2rate (r 0A, r 1A) | 0.254 | ‡ | r 1 = 0.034, t1 = 3.85 | 22.658 | 3.827 |
Bold identifies the best-fit model. AIC’s and the difference in AIC’s with the best model (∆AIC) are shown. IST, incomplete sampling taxa; λ 0A, the initial speciation rate in Arion; μ 0A, the initial extinction rate in Arion; μ 0, extinction rate when applicable; K, carrying capacity parameter of DDL and DDD models; r 0 (= λ 0 − μ0), initial net diversification rate for diversity dependent linear (DDL), diversity dependent exponential (DDX), yule2rate (or constant net diversification rate for pure-birth and birth-death model) and DDD models; r1 = net diversification rate after the first shift at time t1; xp, exponent of DDX model; * package function does not include provision to take into account incomplete taxon sampling; ‡ the parameter in the model is fixed to zero.