Fig. 1
From: Multi-omic insights into the formation and evolution of a novel shell microstructure in oysters
Genomic landscapes of two oysters and the distribution of chalky layer in molluscs. a Circos plots showing conserved synteny between Crassostrea nippona (left) and C. gigas (GenBank accession number: GCA_011032805.1) (right). From outer to inner circle: repeat coverage, GC content, gene distribution, genomic synteny. The sliding window size is 100 kb. b Phylogenetic tree of 16 representative molluscs. Nine nodes with red dots represent reference-calibrated time points (Additional file 2: Table S7). The node with a red hollow star shows the divergence time between Ostreida and Pterioida. The plus signs after species names indicate chalky calcite in the shell; minus signs mean no chalky calcite in the shell. The purple horizontal lines indicate the 95% confidence intervals of divergence times. Numbers of gene families undergoing expansion and contraction for each lineage are shown in red and green, respectively. The color labelling scheme of taxa: Bivalvia (blue), Gastropoda (green), Cephalopoda (orange), Ostreida (brown), Pterioida (purplish red). Periods: Cambrian (Є), Carboniferous (C), Devonian (D), Ediacaran (EDI), Jurassic (J), Cretaceous (K), Neogene (N), Ordovician (O), Permian (P), Paleogene (Pg), Silurian (S), Triassic (T)