Data from: Metagenomic insights into the dietary diversity of the adaptive radiation of cichlid fishes in Lake Tanganyika

Diet specialization is a main driver of diversification in many adaptive
radiations. Therefore, identifying diet items is essential to characterize
trophic specializations and to understand the dynamics of dietary
adaptations. In this study, we explored the trophic niches of 56 species
from the adaptive radiation of cichlid fishes in Lake Tanganyika,
encompassing all major phylogenetic lineages and feeding specializations.
We employed a metagenomic sequencing approach to identify the food sources
of the investigated species at high taxonomic resolution, sequencing over
400 digestive content samples from wild-caught individuals at around 50
million paired-end read depth per sample. Our analyses revealed
Arthropoda, Chordata (fishes), Bacillariophyta and Streptophyta as the
primary diet phyla of the Tanganyikan cichlids. Moreover, we confirmed the
presence of other food sources and identified taxa not previously
documented to be part of the cichlids’ diet. Based on their dietary
compositions, the Tanganyikan cichlids can be grouped into herbivores,
invertivores, piscivores, and mixed-feeders. Further, we showed that
trophic disparity in the radiation is shaped by rapid divergence and
documented cases of dietary niche convergence. Diet composition correlated
with carbon and nitrogen stable isotope values, gut length, and body
morphology. Differences in diet – such as the consumption of diatoms,
streptophytes, and chlorophytes versus fish and arthropods – were
associated with changes in body, upper oral jaw and lower pharyngeal jaw
shape. Collectively, this study presents a comprehensive and detailed diet
classification of the Tanganyikan cichlids, highlighting the power of
metagenomic approaches in delineating dietary adaptations.