[1][2][5] The clade includes species as diverse as giraffes, pigs, zebras, rhinos, dogs, cats, rabbits, mice, squirrels, bats, whales, dolphins, lemurs, monkeys, and humans.

[8] The name of this magnorder comes from Ancient Greek words: The majority of earliest known fossils belonging to this group date to about 66 million years ago, shortly after the K-Pg extinction event, though molecular data suggest they may have originated earlier, during the Cretaceous period.

[9][10] This is further supported with fossils of Altacreodus magnus and two species from genus Protungulatum dated about 70.6 million years ago.

[11][12] The paper's authors claimed that the genome sequence of the boreoeutherian ancestor could be computationally predicted with 98% accuracy, but would "take a few years and a lot of money".

[11] The phylogenetic relationships of magnorder Boreoeutheria are shown in the following cladogram, reconstructed from mitochondrial and nuclear DNA and protein characters, as well as the fossil record.