Carnivore evolution questions

[smiling bandit]

I was curious about the genetic relationships of Carnivores. Clearly, there are several related species - the big branches being wolves, cats, foxes branching early off the wolf line, some other carnivores, etc.

But when did these start to differentiate? What is the last common ancestor of these species? What is the last common ancestor with humans?

[Whack-a-Mole]

Seems the Order Carnivora is the start of your link to the earliest common ancestor of canines and felines. Apparently Family Canidae (which encompasses all of your dog-like animals) diverged early on from other carnivores branching away some 50-60 million years ago. Not sure what their common ancestor looked like (my Google-Fu fails me for some reason on this).

To wrap humans in you need to go even further back to, near as I can tell, the common ancestor for all mammals which seems to be a small, shrew-like animal some 80 million years ago living in Asia (cite ).

[Whack-a-Mole]

Not sure but the best I can tell is perhaps Therapsids are the common ancestor to the order carnivora. Take that with a grain of salt.

[Polycarp]

Originally Posted by Whack-a-Mole

Not sure but the best I can tell is perhaps Therapsids are the common ancestor to the order carnivora. Take that with a grain of salt.

Well, yeah, but only in the sense that they're the common ancestor to all mammals, from platypus to muskox.

Wikipedia has a pretty good article on Carnivora, including some fairly recent reassignments on ancestry within the order. There's a couple of things I consider suspect in Wiki's account of their taxonomy, but I'll take a raincheck and see what someone more familiar with carnivore taxonomy has to say.

Key info you probably wanted, from the article:

Originally Posted by Wikipedia

Carnivorans apparently evolved in North America out of members of the family Miacidae (miacids) c 42 million years ago. They soon split into cat-like and dog-like forms (feliformia and caniformia).

* * *

The divergence of carnivorans from other miacids, as well as the divergence of the two clades within Carnivora, Caniformia and Feliformia, is now inferred to have happened in the middle Eocene (ca. 42 million years ago). Traditionally the Viverravidae (viverravids) had been thought to be the earliest carnivorans with fossil records first appearing in the Paleocene of North America about 60 million years ago, but recently described evidence from cranial morphology now places them outside the order Carnivora.

The Ursidae first occur in North America in the Late Eocene (ca. 38 million years ago) as the very small and graceful Parictis that had a skull only 7 cm long. Like the canids, this family does not appear in Eurasia and Africa until the Miocene. The other caniform families Amphicyonidae, Mustelidae and Procyonidae occur in both the Old World and the New World by the Late Eocene and Early Oligocene.

[John Mace]

Originally Posted by Whack-a-Mole

To wrap humans in you need to go even further back to, near as I can tell, the common ancestor for all mammals which seems to be a small, shrew-like animal some 80 million years ago living in Asia (cite ).

Placental mammals, assuming that 2004 article is still accurate.

But yeah, the primates and the carnivores don't share a common ancestor until you go pretty far back into the family tree of placentals. We're more closely related to rodents.