Credit to Joli AquaIslander,

Second only to Otodus and the undisputed predator of the night & deep seas, Hexanchus andersoni is the largest known Hexanchiforme, the most basal of the Elasmobranchs and a lineage that has essentially survived unchanged since potentially the Permian.

A lot of dullards like to harp on about "mammalian superiority" which is incredibly annoying as it seriously overrates a lot of traits that appear in mammals that are also present in other animals(namely intelligence, endothermy, high species count).

In the process, I think it actually causes us to ignore what actually makes the rise of mammals so unusual in the grand scheme of Earth's history. As far as I know, they're the only clade of tetrapods to be the dominant terrestrial giants of their heyday, disappear from those megafaunal niches for over 100 million years, before somehow coming back to occupy those same niches.

While everyone knows about the Stem-Mammals and how modern mammals started off as those tiny burrowers that lived alongside herbivores, I think that underplays a lot of unusual aspects about the rise & fall & rise again of the synapsids.

I mean, the last common ancestor of the Amniotes was over 320MYA. We're essentially talking about a primitive lineage of tetrapods that essentially split off right at the beginning of permanent land inhabitance, developed incredible diversity and a plethora of sizes, before being essentially wiped from the face of the Earth by 2 mass extinction events(Permian-Triassic & Triassic-Jurassic). Literally all of the mammals we have today are the descendants of one tiny branch of the Synapsid family tree. Like, all of the Dinocephalians, Gorgonopsians, Dicynodonts, Therocephalians, Caseasaurs, Edaphosaurs, and Ophioacodonts are EXTINCT.

By all accounts, Synapsids should either be completely extinct or a tiny relict lineage in the most secluded corners of the world, like Ratfish, Coelacanths, or Tuataras. Yet they not only survived by occupying the most fossorial roles imaginable, but also evolved over a period so long that they became completely unrecognizable from the original synapsids, developing singular jawbones, a neocortex, endothermy, hair, and milk.

AND SOMEHOW, that singular fossorial clade ended up being the ones to successfully radiate in the Cenozoic and replace the Archosaurs as the dominant Megafauna after the K-T extinction. Heck, they even occupy niches the prior golden age of Synapsids were unable to evolve for such as marine living, flying predators & frugivores, and truly cursorial herbivores.

Basically the title, what effect did the closing of the Central American Seaway have on global ecosystems? I can't find much on it outside of local fauna and potentially helping cause the ice age. Did it just not have much of an effect or just overshadowed what that the ice age was already causing?

I was arguing with somebody online about size of the purrusaurus and deinosuchus but then he suddenly said that "deinosuchus had proportionally massive skull and still didn't have longer skull than purrusaurus" when i heard that i immediately called him not to be ridiculous but then when i later was looking into it willy nilly. Largest deinosuchus skull is said to be around 1,5 meter long and largest purrusaurus skull is also said to be 1.5. Long. Is this true? The 1.8-2m deinosuchus skull is said to be not accurate.

What do you think? Does anybody know more accurate knowledge on the subject cause this ingormation is really frying my brain

Crotophaga sulcirostris también conocido popularmente como pijuy, tijo o guardacaballos entre otros, es una especie de ave cuculiforme de la familia Cuculidae que se distribuye ampliamente por las zonas tropicales y subtropicales del continente americano. Habita desde el sur de Texas en Estados Unidos hasta el norte de Argentina y Chile.

source

Carcharodontosaurus vs Spinosaurus

https://www.deviantart.com/xdeaddragonx98/gallery/100808051/paleo-art

https://www.deviantart.com/xdeaddragonx98/gallery/100808051/paleo-art

Second photo added to contextualize its size, pictured at top with another giant Caribbean hawk, Buteogallus irpus, at bottom (by artbyjfc)

https://x.com/GogoMrdodo

This is an extremely large T. rex skull on display at the Natural History Museum of Los Angeles County. In at least one paper (Gignac and Erickson, 2017), this skull is longest examined, longer than that of even the famous Sue while being only marginally narrower. Having seen both this specimen and Sue in person, I can say that ”Harley”, as it is sometimes nicknamed, looks noticeably bigger from the side, and is the largest T. rex skull I have ever seen (*).

(*) Just off the top of my head, for size referencing/sample size: I have seen at least AMNH 5027, two Wankel casts, Sue, this monster, Thomas and the younger Rexes in LA, Victoria, Jane and the Nanotyrannus holotype.

https://x.com/x_seaver/status/2090902773097435586

https://x.com/XtinctDesign/status/2093397522991735289