Whole genome duplication in the genomics era: The hidden gems in invertebrates?

Abstract Whole genome duplication (WGD) results in new potent genomic resources for rewiring the existing genetic regulatory networks in organisms. The exploration of WGD presents a fascinating puzzle to unravel its evolutionary significance. In metazoans, recent studies are now showing different invertebrate lineages, including lophotrochozoans (rotifers and snails) and ecdysozoans (horseshoe crabs, nematodes, scorpions, and spiders), have also undergone WGDs. Nonetheless, the lack of high-quality genomes and standardized methods for detecting WGD pose significant challenges in confirming WGD events. Here we summarised the latest situations and indicated the presence of long-standing WGDs across various invertebrate lineages.