Total evidence phylogeny of ducks, geese and swans
(family Anatidae): implications for macroevolution and
biogeography

Hancocks, G

Abstract

The neornithine bird family Anatidae comprises the ducks, geese and swans, and is one of the largest (approximately 150 species) and most studied families of modern birds. The fossil record of definitive anatids stretches from the Oligocene epoch to the
present. However, the phylogeny of this family remains highly contentious. Historically, the phylogeny of Anatidae has been studied using morphological evidence, but molecular data (primarily mitochondrial sequence data) has become increasingly
available and has been used to resolve relationships within the group, and to resolve the affinities of previously enigmatic taxa. However, molecular data is not available for fossil species, which limits the inferences that can be made. In this study, a novel total
evidence dataset and associated phylogenetic analyses are presented, based on 209 morphological characters of the external soft tissue, cranium, post-cranium and internal soft tissue, as well as 13.4 kb of mitochondrial sequence data for 75 anatid
taxa (72 extant, 3 fossil) and 3 non-anatid outgroup taxa. The resulting phylogeny supports the placement of enigmatic taxa in existing subfamilies, such as the moanalos into Anatinae, and Alopochen aegyptiaca into Tadorninae, corroborating previous studies. The non-monophyly of the now defunct tribe “Cairinini” was also confirmed, with the morphological and behavioural features shared by “cairinins” interpreted here as being the result of convergent evolution. Undated and dated total evidence analyses were carried out, using a Bayesian approach, with the latter
resulting in divergence time estimates that indicate that crown-clade Anatidae originated in the Early Miocene about 19 Ma (95% HPD 14.8-29.0 Ma). The undated and dated total evidence topologies were also used to reconstruct the evolution of
selected macroevolutionary traits (e.g., volancy versus non-volancy, diet, sexual system) and the biogeographical history of anatids, the results show that certain traits; particularly diet, characterize certain clades, such as the piscivorous mergansers and the ubiquitous herbivory of Anserinae.

Citation

biogeography. (Dissertation). The University of Salford

• Thesis Type: Dissertation
• Deposit Date: Oct 5, 2022
• Award Date: Mar 31, 2022