Phylogeny of Procellariiformes
The study of the evolutionary relationships within the order
Procellariiformes had until recently been based mainly in the
phylogenetic analyses of a single gene, the mitochondrial cytochrome b
or on supertree approaches combining life history, morphological and
sequence data (Kennedy & Page, 2002; Nunn & Stanley, 1998;
Penhallurick & Wink, 2016). However, these approaches did not show
enough resolution for this group, leaving several open questions. The
main points that remain contentious are: 1) which family is the sister
to the rest of the Procellariiformes (Diomedeidae or Hydrobatidae), 2)
which is the phylogenetic position of the diving petrels
(Pelecanoides sp. ) and whether they should be placed on their own
family, 3) the monophyly of the storm petrels as well as the
phylogenetic relationships among the speciose Procellariidae (J. J.
Austin, Bretagnolle, & Pasquet, 2004; Brown et al., 2011; Obiol et al.,
2020; Welch, Olson, & Fleischer, 2014). More recently, the first study
to use genomic data to resolve the backbone Procellariiformes phylogeny
(EstandÃa et al., 2021) reported a well-resolved phylogeny of 51 species
using 4,365 ultraconserved elements (UCEs). This phylogeny recovered the
albatrosses (Diomedeidae) as the sister group to the rest of
Procellariiformes, the diving petrels included within Procellariidae,
and the storm petrels constituting a paraphyletic group with Oceanitidae
and Hydrobatidae being two separate monophyletic groups, and
Hydrobatidae as sister group of Procellariidae. Our phylogenomic results
using a smaller taxon sampling but a more extensive phylogenomic dataset
(of up to 6,172 genes), agrees with those of (EstandÃa et al., 2021),
supporting that these phylogenetic relationships are definitive.