Thirdly, genetic drift may strongly constrain adaptive evolution, where small populations suffer from maladaptive genetic differentiation due to influence from random processes [ 10].
In contrast, many other studies have suggested that the homogenising effects of gene flow may often constrain adaptive divergence between natural populations (reviewed e.g. in [ 4, 36]).
Migration and gene flow can interact in complex ways, and can either promote or constrain adaptive divergence through either gene flow or demography [47].
These genetic effects can either enhance or constrain adaptive evolution, depending on the circumstances (review: Garant et al. 2007).
These conditions can potentially lead to strong genetic drift, a process that can constrain adaptive evolution [ 43, 46, 47].
Physiological costs of mutations that greatly increase gene expression, such as these, may constrain their utility for adaptive evolution.
Furthermore, considering the critical importance of eco-morphological niche specialization during the adaptive radiation of African cichlids [ 28], our study indicates that mouthbrooding may constrain the rate of speciation.
This shortcoming may constrain the full potential of their applications.
Differences in oscillation frequency may constrain synchronization for long distances.
Such filtering effects may constrain or even distort communication [ 7].
