These three extant bird taxa nest together
in the large reptile tree (LRT, 1089 taxa) and it’s easy to see why when you look at their skulls (Figs. 1–3). On the inside they are more like each other than any other tested taxa. We usually see them from the outside (Figs. 4–6). Get ready for more heresies…
Figure 1. Scopus umbretta, the extant African hamerkop.
Scopus umbretta (Brisson 1760, 56 cm tall) is the extant hamerkop, a mid-sized wading bird (Figs, 1, 4). In the LRT it nests with the petrel, Macronectes, Note: the maxilla is much longer in these taxa.
Figure 3. Macronectes giganteus, the extant Southern giant petrel.
Macronectes giganteus (Gmelin 1789; 56 cm tall) is the extant Southern giant petrel, a member of the Procellariidae and Procellariformes (tubenoses). Here it nests with Scopus and Pelagornis . This soaring sea bird has a wingspan up to 2m. Note the naris has shifted anteriorly along with the maxilla.
Figure 3. Coragyps atratus, the extant black vulture.
Coragyps atratus (LaMout 1853; 56 cm in length, 1.5m wingspread) is the extant black vulture and a sister to the giant petrel. Note the similar premaxilla. As in Threskiornis(below), the head and neck lack feathers.
Figure 4. Scopus, the hamerkop, in vivo.
One of the current problems in bird phylogeny
is how to tie the various orders of birds together at their roots. Which orders are related to which other orders? Here’s how the situation stands according to Wikipedea:
- Hamerkop family: Scopidae, order: Pelecaniformes
- Petrel family: Procellariidae, order: Procellariformes
- Vulture family: Cathartidae: order: Accipitriformes
According to Wiki:
Pelecaniformes include the pelican, shoebills, hamerkops, ibises, spoonbills, herons, egrets and bitterns. In the LRT, SOME of these disparate taxa nest at disparate nodes. Others have not been tested yet.
Frigate birds, gannets and boobies, cormorants, darters and tropic birds used to be in this clade, but DNA and morphological studies indicate otherwise. “Recent research strongly suggests that the similarities between the Pelecaniformes as traditionally defined are the result of convergent evolution rather than common descent.” None of these have been tested yet. Most have a bare throat patch (gular patch), and the nostrils have evolved into dysfunctional slits, forcing them to breathe through their mouths.
Figure 5. Macronectes, the Southern giant petrel, in vivo.
According to Wiki
Procellariiformes include the petrel and albatross. These, in turn, are most closely related to penguins and loons. The LRT (Fig. 7) finds several taxa nest between penguins and loons, including dippers, kingfishers and hummingbirds, but we’ll save that for another day.
Figure 6. Coragyps, the black vulture, in vivo.
According to Wiki:
Accipitriformes include the New World vultures, the hawk, secretary bird and eagle, but not the falcon and owl. DNA nests falcons closer to parrots and sparrows. Accipitriformes are carnivorous with raptorial claws and a sharply hooked beak, but the same can be said of falcons and parrots. Here (Fig. 7) falcons, like Falco, nest with the terror birds and their extant relatives, not with parrots.
Well, this is embarrassing!
Yesterday’s post had roadrunners linked to herons. Everyone knows roadrunners are a type of cuckoo. Today, with the addition of Coccyzus, the cuckoo, that problem resolves itself. The LRT nests both cuckoos with the heron, Ardea (Fig. 7). This series appears to document another example of serial phylogenetic miniaturization, with a smaller and smaller overall size coupled with shorter legs (neotony) and a return to the down curved rostrum found in the ratite ancestors of herons, like Rhynchotus.
Figure 8. Members of the cuckoo/heron clade along with a baby heron.
As we’ve seen before
DNA results do not match morphological results over larger phylogenetic distances. And the same appears to hold true for extant birds. I thought the birders had this all figured out, but apparently there is room for yet another hypothesis of relationships here. The LRT bird tree topology is, so far, staying pretty simple and logical.
Nullius in verba
Brisson MJ 1760. Ornithologie, ou, Méthode contenant la division des oiseaux en ordres, sections, genres, especes & leurs variétés : a laquelle on a joint une description exacte de chaque espece, avec les citations des auteurs qui en ont traité, les noms quils leur ont donnés, ceux que leur ont donnés les différentes nations, & les noms vulgaires
Gmelin JF 1789. Caroli a Linné … Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, Cum Characteribus, Differentiis, Synonymis, Locis. Editio Decima Tertia, Aucta, Reformata/ cura Jo. Frid. Gmelin. Volume 1, part 3. Lipsiae: Impensis Georg. Emanuel. Beer.
Latham J 1790. Index Ornithologicus, Sive Systema Ornithologiae: Complectens Avium Divisionem In Classes, Ordines, Genera, Species, Ipsarumque Varietates (2 Volumes) (in Latin). London: Leigh & Sotheby.
LeMaout 1853. xx