Schlagwort-Archive: Pumiliornis tessellatus

Just some bullshit found on David Peters‘ website ….

This was posted on David Peters’ website on June 6, 2018.:

Pumiliornis tesellatus [sic] is a wren-sized (shown larger than actual size) Messel pit bird that was originally (Mayr 1999) considered an enigma and later (Mayr 2008) allied with cuckoos. In the large reptile tree (LRT, 1225 taxa) tiny Pumiliornis nests with Platalea, the spoonbill (Fig. 2) as a phylogenetic miniature, close to, but not quite related to the parallel, short-legged genesis of ducks and geese.

I’m not quite sure what this “short-legged genesis” is supposed to be, but the length of the legs does not indicate any relationships between birds but has much more to do with their way of life!

Presbyornis, currently at the base of ducks, still has long legs and a long neck. More derived taxa in the duck branch lose their long legs, although some, like the swan and goose, retain a long neck.

What does that have to do with the genus Pumiliornis or with spoonbills?

Pumiliornis tessellatus (Mayr 1999, 2008; 6cm long; middle Eocene). This wren-sized relative to spoonbills and ancestor to ducks has a spatulate beak tip. This is a neotonous [sic] form of the long-legged spoonbill with juvenile size and proporitons [sic] representing the genesis of a new clade. This fossil contains fossil grains in the cloacal area (white box). Note that no webbing is preserved between the toes. Spoonbills also lack webbed toes.

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No, it is not a relative of the spoonbills, and it is not at all an ancestor to ducks, which by the way already existed anyway back then, which again would make it even harder to be their ancestor ….

No, its beak tip isn’t spathulate ….

Yep, Pumiliornis was a very small bird – that doesn’t make it neotenous, at least not more so than any other Passeriform bird, which are indeed thought of as being somewhat neotenous compared to non-passeriform birds.

No, its proportions are not those of a juvenile spoonbill ….

Yep, the fossil contains fossil grains – pollen grains, since it obviously was a nectar-feeding bird with an elongated beak as is typical for nectar-feeding birds …. 

No, Spoonbills do not lack webbing on their toes, they actually have small webs along the bases of their toes ….

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To think that a small nectar-feeding perching bird is the ancestor of ducks and a relative of spoonbills is, well, funny. To promote that bullshit as if it would be the absolute truth, however, is just insane! 

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I’ll probably take some of my precious time to try to debunk more of David Peter’s nonsense in the future, we’ll see.

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Why the world really should ignore David Peters

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edited: 30.07.2021

Pumiliornis tessellatus Mayr

Pumiliornis means as much as “dwarf bird”, and with that, all has been said.

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No, not so fast ….

The genus/species was described in 1999 and is, to my knowledge, so far known from three skeletal finds, of which one even contains the remains of its last meal, namely pollen.

All in all, Pumiliornis tessellatus resembled today’s sunbirds (Nectariniidae) or the sunbird-asitys (Eurylaimidae) in being very small and having an elongated beak. Its beak, however, was quite unlike those of the members of the beforementioned two families, it resembled the beak of a plover (Charadriidae), especially its narial opening (nose hole), which was rather slit-like and not round.

Pumiliornis was apparently a flower-visitor that fed on nectar and pollen (as is known from the content of the gut of one specimen), however, it may not have been specialized to that diet and may also have taken insects and other small invertebrates.

The bird was small, very small, in my reconstruction it reaches a length of only 7,5 cm, this size, however, is of course depending on the length of its tail feathers, which unfortunately are not preserved in any of the known specimens. I’ve reconstructed the bird with a rather short tail, which may some day turn out to be completely wrong, who knows.

The feet corresponded to the typical scheme of recent passerine birds, i.e. they have three toes pointed forward and one towards the back. However, the feet appear to have been facultative or semi-zygodactyl, which in turn means, in simple terms, the first toe usually pointed forwards, but could be held backward when needed.

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The genus/species originally could not be assigned to any living bird family, not even an order, but is now known to belong to the extended Passeriformes-orbit, which in addition to the passerine birds also includes the falcons (Falconiformes) and the parrots (Psittaciformes). It is now known to have been a member of the extinct family Psittacopedidae, that apparently also contains other unusual genera like MorsoravisPsittacopes and the recently described, very interesting Eofringillirostrum and probably others too.

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Finally, it should be mentioned that this bird was not a dwarf spoonbill, as claimed by a certain person.   😉

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References:

[1] Gerald Mayr: Pumiliornis tessellatus n. gen. n. sp., a new enigmatic bird from the Middle Eocene of Grube Messel (Hessen, Germany). Courier Forschungsinstitut Senckenberg. 216: 75-83. 1999
[2] Daniel T. Ksepka; Lance Grande; Gerald Mayr: Oldest finch-beaked birds reveal parallel ecological radiations in the earliest evolution of Passerines. Current Biology 29: 1-7. 2019

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edited: 08.02.2019