Agamids show a certain level of morphological convergence with iguanids whereas chamaeleonids are morphologically quite unique in various organs, such as eye, tongue, tail, and toe [ 1].
Using multivariate morphometric analysis, we find that phylogenetically unrelated taxa have convergently evolved troglomorphism; alternative phylogenetic hypotheses involving less morphological convergence are not supported by Bayesian hypothesis testing.
A major difficulty of detecting such phenomena is that they are expected to exhibit morphological convergence, which would obscure evolutionary relationships reconstructed on the basis of morphology alone.
Morphological convergence in lifestyle and associated morphological features appear to have confounded past morphologically-based analyses of blenny relationships, especially among the tube-dwelling lineages.
Despite the similarities between the three species, the three have been shown to be in different clades within Gymnopilus, suggesting ecological convergence between G. arenophilus and G. maritimus, and morphological convergence between G. fulgens and G. maritimus.
This implies an independent colonisation of the underworld in Australia and morphological convergence.
Furthermore, the rapid divergence of the genus Aphis likely affected the morphological convergence that more characterizes each species-group.
There is a proliferation of cryptic species in subterranean habitats both because of limited study due to difficult access and rampant morphological convergence in the face of strong, similar selective pressures [7], [8], [43].
Molecular phylogenetic and clock analyses can help to cut through the confusion of morphological convergence to help to resolve the evolutionary and biogeographic history of subterranean taxa [41] [43].
The isolation and strong selective pressures inherent in the adoption of an underground life can lead in polar opposite directions, namely both genetic divergence and morphological convergence [6], which can greatly confound interpretation [7] [9].
Morphological convergence among radiations suggests deterministic evolution is strong enough a force to overcome variation in phylogenetic background and ecological setting that may differentially constrain the morphological 'space' available to diversifying lineages [1] [4].
