“…The precise definition of a group of orthologous genes, however, depends on the particular method used, and several methods and algorithms to cluster orthologous genes have been proposed, including blast searches, Markov clustering, spectral clustering and hierarchical orthology. Several similarity-based methods are commonly used in phylogenetics and functional genomics, including orthomcl (Li, 2003), cog (Tatusov et al, 2003), inparanoid (O'Brien, 2005), oma (Roth, 2008), proteinortho (Lechner et al, 2011), eggnog (Powell et al, 2012), orthofinder (Emms & Kelly, 2015), orthograph (Petersen et al, 2017) and orthodb (Kriventseva et al, 2019). By contrast, phylogeny-based methods aim to identify orthologues by inferring the lowest common ancestor relationships between genes, which is performed by estimating a gene tree and identifying its speciation and duplication events using reconciliation with a species tree (Ullah et al, 2015).…”