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Table 1 Models of calf and juvenile survival.

From: The role of menopause and reproductive senescence in a long-lived social mammal

  Calf survival Juvenile survival
Model BIC Pr [M|Y] Pr [M|Y] v. null BIC Pr [M|Y] Pr [M|Y] v. null
null 177.7 0.29 - 419.4 0.14 -
age - - - 416.9 0.51 0.78
age + age2 - - - 418.1 0.28 0.66
time 183.3 0.02 0.06 426.2 0.01 0.03
moms > 35 (F) 176.5 0.51 0.64 424.2 0.01 0.09
birth order 180.9 0.06 0.17 423.7 0.02 0.11
first born (F) 181.9 0.03 0.11 422.1 0.04 0.21
momAge 180.5 0.07 0.19 - - -
grandmaAlive 182.6 0.02 0.08 - - -
  1. Models of calf survival (from age 0 to 1) were applied to 329 whales to evaluate maternal effects (binomial response) and for juvenile survival (ages 0 to 5) for 1411 whale-years (337 animals). In the latter comparison, juvenile survival was held constant (models that allowed survival to vary as a function of juvenile age were also considered, but the results did not change). All ages in the table refer to the age of the mother; birth order was treated as a continuous variable. Model selection tools like BIC are preferable over traditional significance tests, because they can be used to estimate model probabilities, Pr [M|Y]. For each model, we also calculated the probability for model i relative to the null model (constant survival, intercept only), Pr [M i |Y]/(Pr [M null |Y] + Pr [M i |Y]).