New passerine genomic study not confirmed by phenomic study

Oliveros et al. 2019
produced an exhaustive DNA study from 137 passerine families, then calibrated their phylogeny using 13 fossils to examine the effects of different events in Earth history on the timing and rate of passerine diversification.

Unfortunately
the large reptile tree (LRT, 1434 taxa) produced a different tree because it uses phenomic traits, not genes.

The two trees both started with birds of prey, including owls.
Then they diverged. The Oliveros team recovered 137 families of passerines arising from highly derived parrots, arising from highly derived owls.

The LRT recovered highly derived parrots arising from the more primitive hoatzin Opisthocomus, arising from the more primitive sparrow, Passer, arising from the more primitive grouse + chickens + peafowl and kin going back to Early Cretaceous Eogranivora. In the LRT owls give rise to birds of smaller prey: owlets, like Aegotheles, and swifts, like Apus, not herbivorous parrots.

Figure 1. Skeleton of the common house sparrow, Passer domestics.

Figure 1. Skeleton of the common house sparrow, Passer domestics. Note the heavy, seed-crunching beak, a precursor for the heavier see-crunching beak in parrots, not the other way around.

Among the traditional ‘passerines’ tested by the Oliveros team
are the distinctively different crows (genus Corvus) and nuthatches (genus Sitta). These clades nest apart from each other in the LRT and apart from Passer, the sparrow. In the LRT, crows and nuthatches are not Passerines, but parrots and hoatzins are passerines. Sometimes competing cladograms can be topsy-turvy like that, with similar sister taxa flipped with regard to primitive and derived. Earlier I mentioned ‘woodpeckers’, which have never been considered passerines, because woodpeckers and nuthatches are sisters in the LRT.

Robins (genus: Turdus) are considered passerines in the DNA study. They are crow relatives in the LRT. Jays (genus: Cyanocitta) and grackles (genus: Quiscalus) are crow relatives in the LRT. Neither are included in the DNA study that includes crows (genus: Corvus).

Figure 1. Several birds with zygodactyl feet (light red) and one member of the clade Zygodactylidae (red).

Figure 2. Subset of the LRT focusing on birds. This is how they are related to one another based on phenomic traits. Note the presence of Passer nesting between the chicken, Gallus and the parrot, Ara. Other purported passerines, like Turdus, Corvus and Sitta,  nest in other clades here.

So, once again,
when taxonomists use genomic (DNA) tests they run the risk of wasting their time when dealing with deep time taxa. Some paleo and bird workers put their faith in DNA, hoping it will recover relationships because it works well in humans. Unfortunately, too often phenomic tests are at odds with genomic tests to put  faith in genomic tests. Only phenomic (trait) tests recover cladograms that produce a gradual accumulation of traits among sister taxa, echoing deep time events. Only phenomic tests can employ fossils. Let’s not forget our fossils.

A suggestion for Oliveros et al. 2019:
test your results against your own phenomic study. If valid, both of your results will be the same. If not, one of your tests needs to be trashed.


References
Oliveros CH and 31 co-authors 2019. Earth history and the passerine superradiation.

www.pnas.org/cgi/doi/10.1073/pnas.1813206116

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