Table 2.
Scaling parameters of evolution for the continuous characters analysed following Pagel (1999), and their implications for the pattern of evolution of these characters
| Character | κ | Branch length scale | λ | Contribution of phylogeny | δ | Total path scale | Model A | Model B | LR |
|---|---|---|---|---|---|---|---|---|---|
| Sieve-tube areas | 0·0* | Punctuational evolution | 0·0* | Star phylogeny (species-independent) | 3·0* | Temporally later change (species-specific adaptation) | –225·65 | –226·22 | –1·14 |
| Variant parenchyma (%) | 1·1 | Default gradualism | 0·28* | Minimal effect of phylogeny | 3·0* | Temporally later change (species-specific adaptation) | –176·79 | –177·66 | –1·75 |
| Fibres in variant phloem of the entire tribe (%) | 0·27* | Stasis in longer branches | 0·81 | Default phylogeny | 1·33 | Default gradualism | –207·64 | –208·03 | –0·78 |
| Fibres in variant phloem of ‘Fridericia and allies extended clade’ (%) | 0·44* | Stasis in longer branches | 0·33* | Minimal effect of phylogeny | 2·8* | Temporally later change (species-specific adaptation) | –77·28 | –87·30 | –20·04 |
| Fibres in variant phloem of ‘Multiples of four extended clade (%) | 0·16* | Stasis in longer branches | 0·99 | Default phylogeny | 0·68* | Adaptive radiation | –69·35 | –70·43 | –2·17 |
| Number of sieve areas in variant phloem of ‘Fridericia and allies extended clade’ | 2·28* | Longer branches accumulate more changes | 1·0 | Default phylogeny | 0·30* | Adaptive radiation | –60·74 | –60·77 | –0·06 |
| Number of sieve areas in variant phloem of ‘Multiples of four extended clade | 0·0* | Punctuational evolution | 0·94 | Default phylogeny | 0·54* | Adaptive radiation | –46·75 | –54·15 | –14·80 |
*Significant deviations from 1·0 for the scaling parameters values kappa (κ), lambda (λ), and delta (δ), assessed with the likelihood ratio (LR) test.
LR values greater than 2 indicate directional evolution.