The phrase "allow for invariable" is not correct and does not convey a clear meaning in written English.
It seems to be an attempt to express the idea of accommodating something that does not change, but the phrasing is awkward and unclear.
Example: "We need to allow for invariable factors in our calculations to ensure accuracy."
Alternatives: "account for constant" or "consider unchanging".
The branch-specific models allow for variable ω ratios among branches but invariable ω ratios in sites in the tree and can be implemented for the study of changes in selective pressures in specific lineages [41], [79].
In addition, the proportion of invariable sites and a gamma distribution parameter to allow for rate heterogeneity among sites (six categories) and uniform prior probabilities and tree topologies were implemented in the analyses.
In all cases, the best model was determined to be the general-time-reversible substitution model [68], [69], with among-site-rate-heterogeneity modeled according to a gamma distribution [70] while allowing for a proportion of invariable sites (I) [71].
We used jModelTest [ 48] to determine the best substitution model for each data set, which in nearly all cases was the General-Time-Reversible (GTR) model [ 49, 50], with among-site rate heterogeneity modeled according to a gamma distribution [ 51] while allowing for a proportion of invariable sites (I) [ 52].
The rate variation model allowed for some sites to be evolutionarily invariable ([+I], 9.0566% sites).
The rate variation model allowed for some sites to be evolutionarily invariable.
All analyses were conducted allowing for a proportion of sites to be invariable (I).
The model used was the generalized time-reversible (GTR) model of sequence evolution, allowing for among-site rate variation and a proportion of invariable sites.
Bayesian trees were obtained using MrBayes [19], and nucleotide sequences, under the GTR model of sequence evolution, thus allowing for among-site rate variation and a proportion of invariable sites.
The GTR model of sequence evolution was used, allowing for among-site rate variation and a proportion of invariable sites.
