Temporal Patterns of Diversification across Global Cichlid Biodiversity (Acanthomorpha: Cichlidae)

Abstract

The contrasting distribution of species diversity across the major lineages of cichlids makes them an ideal group for investigating macroevolutionary processes. In this study, we investigate whether different rates of diversification may explain the disparity in species richness across cichlid lineages globally. We present the most taxonomically robust time-calibrated hypothesis of cichlid evolutionary relationships to date. We then utilize this temporal framework to investigate whether both species-rich and depauperate lineages are associated with rapid shifts in diversification rates and if exceptional species richness can be explained by clade age alone. A single significant rapid rate shift increase is detected within the evolutionary history of the African subfamily Pseudocrenilabrinae, which includes the haplochromins of the East African Great Lakes. Several lineages from the subfamilies Pseudocrenilabrinae (Australotilapiini, Oreochromini) and Cichlinae (Heroini) exhibit exceptional species richness given their clade age, a net rate of diversification, and relative rates of extinction, indicating that clade age alone is not a sufficient explanation for their increased diversity. Our results indicate that the Neotropical Cichlinae includes lineages that have not experienced a significant rapid burst in diversification when compared to certain African lineages (rift lake). Neotropical cichlids have remained comparatively understudied with regard to macroevolutionary patterns relative to African lineages, and our results indicate that of Neotropical lineages, the tribe Heroini may have an elevated rate of diversification in contrast to other Neotropical cichlids. These findings provide insight into our understanding of the diversification patterns across taxonomically disparate lineages in this diverse clade of freshwater fishes and one of the most species-rich families of vertebrates.

Continental cichlid radiations: functional diversity reveals the role of changing ecological opportunity in the Neotropics

“…Previous analyses also observed convergence in dietary specialization and ecomorphology among cichlid taxa from South and Central America [28], and parallels in multivariate ecomorphological divergence between Central American heroines and South American cichlids [22]. Lineage diversification analyses further identified an increase in net diversification rate within Heroini compared with other Neotropical cichlids, possibly associated with increased speciation following ecological release [12,37]. While ecological release is probably an important determinant in island radiations [1,12,62], we find that, in Neotropical cichlids, release from competition also may have facilitated diversification at a broader geographical scale, contributing to the diversity of forms present in modern Central American lineages.…”

“…In contrast to the relatively recent and geographically restricted African Rift Lake cichlid adaptive radiations [7,30 -36], Neotropical cichlids provide a system in which to examine whether ecological opportunity and release drive diversification on broader geographical and temporal scales [6,22,37] as well as intrinsically different aquatic ecosystems (i.e. lakes versus rivers).…”

Taxonomy and systematics of the herichthyins (Cichlidae: Tribe Heroini), with the description of eight new Middle American Genera

“…Given the age (McMahan et al 2013;Říčan et al 2013) and morphological diversity of the herichthyin cichlids, it seems that a substantial amount of extinction in this (once likely far more diverse) Middle American clade has likely occurred. Most of the herichthyin species are distributed in northern Middle America, and many of these species have an origin that can be traced back to this region (Říčan et al 2013;Matamoros et al 2015).…”

Diversity in Fish Auditory Systems: One of the Riddles of Sensory Biology

“…Cichlids are a speciose family of freshwater fishes comprising more than 1000 species ( Figure 14B; McMahan et al, 2013). They exhibit a large diversity in swim bladder size and in the relationship between swim bladder and inner ears (Dehadrai, 1959;Schulz-Mirbach et al, 2012.…”

“…Modified from Schulz-Mirbach et al (2012). (B) The illustrated phylogeny is modified from McMahan et al (2013). Identical colors used in species names, audiogram and the phylogeny indicate the subfamily or tribe to which the studied species belong.…”