#pelagornithids

[a-dinosaur-a-day]

Which palaeontological data gap or debate would you most like resolving?

what the fuck are pelagornithids and where the heck do they go

[thedrawinggizzard]

Pelagornis is known to be one of the largest birds to have ever flown, so i drew the three species in the genus that aren't that:P

[alphynix]

Spectember 2023 #04: Some Aukward Birds

An anonymous submitter asked for a "penguin/auk-like relative of Pelagornis":

Odontopinguinus vomitus represents an unusal early branch of the pelagornithids that didn't take up long-distance soaring, instead specializing for a pursuit diving lifestyle convergently similar to that of the contemporaneous early penguins, and the later auks and plotopterids.

About 1.2m tall (~4'), it has a more slender spear-like beak than its relatives, with forward-pointing pseudotooth serrations. Like other pelagornithids these "teeth" are fairly fragile, so it feeds primarily on soft-bodied fish and squid, pursuing them underwater with wing-propelled underwater "flight".

Much like procellariiformes they're also rather stinky birds, producing musky preen oil and projectile vomiting foul-smelling stomach contents at threats and rivals.

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And another anon wanted to see a "big flightless marine duck":

Thalassonetta anambulatus is descended from the already mostly-flightless steamer ducks. At around 2m long (6'6") it's massive for a waterfowl, with vestigial wings and large webbed feet used to propel itself while diving.

With its rather elongated and heavy body and loon-like leg configuration it's no longer able to walk on land – and it's actually almost fully aquatic, only awkwardly hauling out into isolated island beaches to molt and breed.

It feeds mainly on molluscs, crustaceans, and other marine invertebrates, using the large lamellae in its bill to strain them out of soft seafloor sediments.

[paleopinesofficial]

It would be really cool if you guys added more avian dinosaurs (extinct, of course). There are so many kinds and they get slept on heavily - and yeah, you guys focus on the Mesozoic, but there are Mesozoic ones! And you have Paleozoic things, so why not Cenozoic dinosaurs? Gastornis!!!!! Terror Birds! Pelagornithids! Enantiornithines!!!! Hesperornis!!! The possibilities are endless, and you can list them as Theropods and that's nice :D

This is a great suggestion! We're not working on something like this right now, but I've passed this over to our team to consider if we're ever able to!

[otussketching]

Fossil Novembirb: Day 16 - Among The Giants

During the Oligocene epoch, 33-23 million years ago, the landscape of Mongolia was as endlessly vast and wild as today. Forests were rare in this part of the world, instead there were shrublands, savannahs and deserts there. This landscape was the realm of giants, like the Paraceratherium of Walking With Beasts fame. Birds were also living in this land of giants, and some were already adapting to it.

Heterostrix: A small early owl, roughly the size of modern pygmy owls. But despite its small size, it was a capable predator of large insects, lizards and mammals, even birds as large as itself.

Agnopterus: One of the earliest known true flamingoes. Little is known of this bird, but it likely fed on tiny crustaceans filtered from the water, as do modern flamingoes.

Sonogrus: One of the flightless paleognath birds that was closely related to ostriches. This fleet footed herbivore belonged to the group known as paragruids.

Ergilornis: Another stem-ostrich in the group known as ergilornithids. The inner toe of these birds was reduced in size to allow for more efficient running.

Caspiodontornis: One of the few pelagornithids known from Asia, this pseudotoothed giant flew above the remnants of the ancient Tethys Sea.

[kariachi]

One thing to love about looking at prehistoric critters is, if we had been there, grown up then, they'd just be fucking normal. If you grew up with entelodonts and pelagornithids, they'd just be those fuckers wandering around, and if somebody showed you a picture of a lion you'd be like 'oh damn'.

It's just, a nice thing to think about.

[harpagornis]

Why do frigatebirds lack wing slots?

Unlike other seabirds like albatrosses, which use dynamic soaring, frigatebirds are thermal soarers, riding on air collumns that form above the sea. Thermal soaring is, however, more often associated with continental flyers like storks, large raptors, ravens and cranes, which makes sense as continental settings tend to produce collumns of hot air.

These flyers also have a thing frigatebirds lack: wing slots.

Wings of the American Black Vulture Coragyps atratus.

The only other marine soarers with wing slots I know off are pelicans, and these tend to just as easily soar in continental settings. So what gives?

I don’t think an actual study has been conducted as to why frigatebirds lack these slots otherwise fundamental for thermal soarers. Closest I’ve found was Liu et all 2021, and that doesn’t explore the aerodynamics of frigatebird wings (even lumping them with dynamic soarers, which is flat out wrong).

My best guess is that, unlike most thermal soarers, frigatebirds are rather acrobatic. They routinely chase after other birds in flight and pursue flying fish; this might mean that a sharper wing shape is more desirable, much as in falcons, skuas and other aerial predators. The sheer size of frigatebird wings – some of the proportionally largest among living birds – might compensate for this, and as you can see in the above picture they do angle them forward, likely further macking up for the lack of slots.

What does this means for pelagornithids?

Pelagornis sandersi silhouette by corvarts. Note wing slots.

Another lineage of sea birds, the massive pelagornithids, were also thermal soarers. Unlike frigatebirds, however, I doubt these were acrobatic flyers, seeing as they were much larger. Thus, I think wing slots might be more appropriate in future depictions of these birds.

[sina-man]

Eocene ukraine paratethys:

Basilotritus uheni caught an unlucky pelagornithid

[greypetrel]

At the risk someone already asked these: 🧡 and 🦖

Hi Aimée! ;D Yes, they've both been asked, and both here, but they both could do another round.

Tis the prompt list

🧡 A color you can’t stand?

The only colour I stand little is nude pink/pinkish beige. I hold very very little love for beiges in general (not taupe. Taupe is lovely and so useful and another shade!).

Going for colours I would never ever paint a wall in or buy clothes/items into...

Neon colours, in paticular neon yellow (such a cold shade!). they're good in cyberpunk aesthetic, mind me: I don't have that kind of aesthetic and style, and I can't use them in a way I like. They're too bright for me. And as for clothing: I look awful. xD Cold yellows aren't something I like much, as much as I adore warm ones.

🦖 Favorite extinct animal?

Other than remembering the Helicoprion , which come on how can you not love him, he's so silly with his circular saw mouth.

The Pelagornithid.

Which is a giant albatross, with a wingspan of 6m/20 feet... and teeth on his beak. Because why not. Coleridge would have nightmares for months.

Also: the Moa. Flightless birds are always a joy to witness: think of a giant kiwi, 2m tall. I don't know, they're proporstions make me smile, there's always need for another giant bird that can't fly.

[quark-nova]

Hey, tumblr seems to not have notifications working well for me. Just to say I answerred the pelagornithid post.

Thanks! Notifications work well for me, although I still don't have polls :(

[a-dinosaur-a-day]

dinos are so weird that penguins didn't even make the top ten

[chirrups]

Okay but as a fellow bird obsessed person I NEED to know if you have a passing fixation on prehistoric raptors because that happened to me reccently where I went "man I learnt so much about birds...I need more" so I just started looking at beta birds fhdjsvjs

YES! SAME! but bro it was very much NOT in passing, i've been a theropod nerd since i was like seven years old.

i've been on the "MORE DINOS" propaganda juice for a while lmao. it's a pretty pervasive thing in my hermitcraft grian design (and by extension most other "avian" designs as well) because early raptor anatomy is just so much easier to blend with humans than modern birds

but yes! the entire saurian family tree is WILD. avian dinosaurs are popular ones but there are some fun relatives like toothed seabirds (pelagornithids) and the "opposite birds" (enantiornithes) that are just so fascinating.

they recently started reorganizing the troodon taxon too (as it was basically used as a catch-all for any raptors that didn't fit existing families and genus), so we might get even more prehistoric raptor groups in the future

i've just been latching onto PBS EONS videos for my avian dinosaur fix so far. but holy shit if you haven't, go watch Dead Sound's Dinosauria series and Making of follow-ups. he's an incredibly talented storyteller and is a god at integrating scientific fact with fiction. while he does cover all dinosaurs, not just avian ones, he's very knowledgable about the paleontology scene and i learned so much by just hearing him talk about the dinosaurs he was covering

[alphynix]

Weird Heads Month #29: Giant Saw-Toothed Birds

The pelagornithids, or "pseudotooth birds", were a group of large seabirds that were found around the world for almost the entire Cenozoic, existing for at least 60 million years and only going completely extinct just 2.5 million years ago.

Their evolutionary relationships are uncertain and in the past they've been considered as relatives of pelicaniformes, albatrosses and petrels, or storks, but more recently they've been proposed to have been closer related to ducks and geese instead.

Whatever they were, they were some of the largest birds to ever fly, and many of the "smaller" species still had wingspans comparable to the largest modern flying birds.

But their most notable feature was their beaks. Although at first glance they look like they were lined with pointy teeth, these structures were actually outgrowths of their jaw bones covered with keratinous beak tissue. While these bony spikes would have been useful for holding onto slippery aquatic animals like fish and squid, they were actually hollow and relatively fragile so pelagornithids must have mainly caught smaller prey that couldn't thrash around hard enough to break anything.

The serrations also only developed towards full maturity, and the "toothless" juveniles may have had a completely different ecology to adults.

Pelagornis chilensis here was one of the larger species of pelagornithid, with a wingspan of 5-6m (16'4"-19'8"), known from the western and northern coasts of South America during the late Miocene about 11-5 million years ago.

Like other pelagornithids it was highly adapted for albatross-like dynamic soaring, with long narrow wings that allowed it to travel huge distances while expending very little energy – but with its proportionally short legs it would have been clumsy on the ground and probably spent the vast majority of its life on the wing, only returning to land to breed.

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Nix Illustration | Tumblr | Pillowfort | Twitter | Patreon

[regaliceratops]

Dasornis emuinus, a pseudo-toothed pelagornithid bird from the Eocene of Europe. The pointed projections on its beak were adaptations for holding onto slippery fish that it snapped up in its ocean environment. Its life history was likely similar to modern albatrosses, though it was even bigger, topping out at a likely 20 ft. wingspan.

[otussketching]

Fossil Novembirb: Day 3 - Race to the Sea

During the start of the Cenozoic, the oceans were relatively empty. Gone were the great marine reptiles like mosasaurs and plesiosaurs, as were ammonites and many large predatory fish. As soon as birds could, they entered the ocean to reap its bounties, whether by flying over the surface or diving to the depths. This is especially evident in Aotearoa (New Zealand), where lots of early seabirds, including the first penguins, were found in Paleocene sediments dating about 62 million years ago.

Kumimanu: One of the largest known penguins, and one of the earliest, standing over 1,5 metres tall and weighing 90-150 kilograms.

Sequiwaimanu: Another early penguin, known from a skull that preserves a long, spear-like beak.

Muriwaimanu: A relatively small early penguin. Like other early penguins, it had relatively long legs and somewhat flexible wings.

Kupoupou: A small early penguin with derived traits, like a flipper-like wing and short legs.

Waimanu: The earliest known penguin, and also relatively large at the size of the modern king penguin (Aptenodytes patagonicus)

Protodontopteryx: The earliest known pelagornithid, large soaring marine birds. This earliest member of the family sports a "modest" 2-metre wingspan.

Clymenoptilon: An early representative of tropicbirds that may have lived somewhat like a tern.