#miacis

[princefluph]

Woah a 4th page?? Yeah Ive got a problem

[isimp4shrimp]

Diatryma (Gastornis) chasing a small miacid through the mid-eocene brush

[vhsdogs]

timeline of the evolution of the dog spanning over 50~ million years 🌿

(not 100% accurate but I tried my best)

[alphynix]

It Came From The Wastebasket #06: Messy Miacids

Most modern meat-eating placental mammals are carnivorans, a group that contains two distinct lineages: the feliforms (cats, hyenas, mongooses, viverrids, civets, linsangs, and euplerids) and the caniforms (dogs, bears, seals, raccoons, and mustelids).

The closest living relatives of these animals are pangolins, and their last common ancestor probably lived sometime between the Late Cretaceous and early Paleocene. But the actual early evolutionary history of the carnivorans themselves is rather murkier.

The earliest known carnivoran-like forms – known as carnivoramorphs – all looked vaguely-genet-like and were an ecologically diverse bunch of small predators, ranging from weasel-sized tree-climbers to fox-sized ground-based hunters, found all across North America and Eurasia during the Paleocene and Eocene. They lacked most of the anatomical specializations of true carnivorans, and didn't quite fit into either the feliforms or caniforms, but their distinctive carnassial teeth make it obvious they were still very closely related.

From their initial discovery in the late 19th century, through to the late 20th century, these carnivoramorphs were traditionally all lumped together under the name "miacids". As a result the group quickly turned into a big wastebasket taxon of similar-looking animals, all united more by just not being true carnivorans than by any shared characteristics between themselves.

Miacis parvivorus

But during the last couple of decades this mess has finally started to get cleared up. One distinct lineage of miacid-like animals called viverravids were split off, now thought to be the one of very earliest branches of the carnivoramorph evolutionary tree. Several other "miacids" have also been reassessed and renamed, reclassified as falling into various points in an evolutionary grade between viverravids and true carnivorans, and a couple of species even turned out to actually be caniforms.

The true carnivorans arose from somewhere within the "miacids" during the mid-Eocene, but it's still unclear where exactly to draw the taxonomic line between them. Forms like Quercygale and Tapocyon might be very close to the ancestral carnivoran – but they might instead be early feliforms – and some studies have also proposed that nimravids ("false sabertooth cats") may actually be "advanced" carnivoramorphs instead of early feliforms.

There are also quite a few remaining "miacids" that still need sorting out, especially in the genus Miacis. There have to be other distinct lineages of these carnivoramorphs still hidden in the remaining wastebasket pile, and if we can eventually distinguish them from each other it might help to make early carnivoran relationships a bit clearer.

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[leacherous]

So many miacis!

[gyppygirl2021]

Peruti makes me happy because there are Miacis all over the place and Miacis are the best things ever

I want to hug a Miacis I want a billion Miacis I just

MIACIS

[palaeopedia]

The mother animal, Miacis (1872)

Phylum : Chordata Class : Mammalia Order : Carnivoromorpha Superfamily : Miacoidea Genus : Miacis Species : M. australia, M. cognitus, M. deutschi, M. exiguus, M. gracilis, M. hargeri, M. hookwayi, M. latidens, M. lushiensis, M. medius, M. parvivorus, M. petilus, M. rosi, M. sylvestris, M. thailandicus, M. washakius, M. winkleri

Late Paleocene/late Eocene (55 - 33 Ma)

30 cm long and 1 kg (size)

Eurasia (map)

The genus Miacis contains extinct species of carnivorous mammals that appeared in the late Paleocene and continued through the Eocene. The genus Miacis is not monophyletic but a diverse collection of species that belong to the stemgroup within the Carnivoramorpha. As such, most Miacis species belong to the group of early carnivores that represent the ancestors of the modern order, the crown-group Carnivora. However, the species Miacis cognitus is placed not in the stem-group but among the Caniformia, one of the two suborders of the crown-group Carnivora.

Miacis species were five-clawed, about the size of a weasel, and lived on the North American and European continents. They retained some primitive characteristics such as low skulls, long slender bodies, long tails, and short legs. Miacis retained 44 teeth, although some reductions in this number were apparently in progress and some of the teeth were reduced in size.

The hind limbs were longer than the forelimbs, the pelvis was doglike in form and structure, and some specialized traits were present in the vertebrae. It had retractable claws, agile joints for climbing, and binocular vision. Miacis and related forms had brains that were relatively larger than those of the creodonts, and the larger brain size as compared with body size probably reflects an increase in intelligence.

[anisekairikie]

Miacis the Aerodactyl

When introduced to the team, Miacis called Will "Dad". Eventually Will "adopted" Miacis and shared some of his knowlege with his son. As a result, Miacis became as naughty as his dad and started pulling pranks as well. He's not brave and proud like most Aerodactyl, but he likes showing off infront of ladies. He introduces himself as the AMAZING Miacis...

Now THOSE are scars, and he got them recently too! I had left Miacis with the other "boxed" pokemons, including his "cousin" Senel. Senel is normally a nice Salamence and used to get along very well with Mia, but since Largo, my Charizard, left at the beginning of the Battle Frontier on Ohana, Senny got...harsh.

I have no idea what really happened, all I know is that Senel attacked Miacis and it resulted with that scar. Miacis was even more scared than before.

Though, according to my cousin, who is taking care of my "boxed" pokemons, Miacis has been hanging alot with an unknown shiny female Arbok. Neither I nor my cousin own an Arbok so it got us worried, but it seems to be doing wonders to Mia's courage and will. Rumors go that said Arbok gave Mia that headband he wears all the time now, but I have my doupts.

He still cherish that skitty chew toy he got from Dan on Christmas <3