Table 6 Predictions of male An. gambiae age-grade as a function of their morphology, as obtained from the optimally performing breakpoints model. Text indicates whether males of a particular trait combination would be classified as being ≤ 4 days old (YOUNG), or older (OLD). Numbers in parentheses give the probability of males with a particular trait combination being in the 'OLD' age group, with the model categorizing all males with a probability of lower < 0.5 as being 'YOUNG', and 0.5 ≥ as being 'OLD'. Following this classification guide, the age status of 'YOUNG' and 'OLD' male An. gambiae should be correctly predicted on 81% and 95% of occasions respectively.
From: A reliable morphological method to assess the age of male Anopheles gambiae
Proportion of testis occupied by sperm reservoir | Age class as predicted by the optimal model (BREAKPOINTS) | |
|---|---|---|
Clear area absent | Clear area present | |
≤ 30% | YOUNG (0.26) | YOUNG (0.04) |
31%–60% | YOUNG (0.31) | YOUNG (0.05) |
61%–90% | OLD (0.93) | OLD (0.62) |
> 91% | OLD (0.98) | OLD (0.98) |