Boreoeutheria (, "northern eutherians") is a
magnorder of
placental mammals that groups together superorders
Euarchontoglires and
Laurasiatheria
Laurasiatheria (; "Laurasian beasts") is a superorder of Placentalia, placental mammals that groups together true insectivores (eulipotyphlans), bats (chiropterans), carnivorans, pangolins (Pholidota, pholidotes), even-toed ungulates (Artiodacty ...
.
giraffe
The giraffe is a large Fauna of Africa, African even-toed ungulate, hoofed mammal belonging to the genus ''Giraffa.'' It is the Largest mammals#Even-toed Ungulates (Artiodactyla), tallest living terrestrial animal and the largest ruminant on ...
s, pigs, zebra
Zebras (, ) (subgenus ''Hippotigris'') are African equines with distinctive black-and-white striped coats. There are three living species: Grévy's zebra (''Equus grevyi''), the plains zebra (''E. quagga''), and the mountain zebra (''E. ...
s, rhinos, dogs, cats, rabbit
Rabbits are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha (which also includes pikas). They are familiar throughout the world as a small herbivore, a prey animal, a domesticated ...
s, mice
A mouse (: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...
, squirrel
Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...
s, bats, whale
Whales are a widely distributed and diverse group of fully Aquatic animal, aquatic placental mammal, placental marine mammals. As an informal and Colloquialism, colloquial grouping, they correspond to large members of the infraorder Cetacea ...
s, dolphin
A dolphin is an aquatic mammal in the cetacean clade Odontoceti (toothed whale). Dolphins belong to the families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the New World river dolphins), Pontopori ...
s, lemur
Lemurs ( ; from Latin ) are Strepsirrhini, wet-nosed primates of the Superfamily (biology), superfamily Lemuroidea ( ), divided into 8 Family (biology), families and consisting of 15 genera and around 100 existing species. They are Endemism, ...
s, and simians
The simians, anthropoids, or higher primates are an infraorder (Simiiformes ) of primates containing all animals traditionally called monkeys and apes. More precisely, they consist of the parvorders New World monkey, Platyrrhini (New World mon ...
(monkeys
Monkey is a common name that may refer to most mammals of the infraorder Simiiformes, also known as simians. Traditionally, all animals in the group now known as simians are counted as monkeys except the apes. Thus monkeys, in that sense, co ...
and apes).
With a few exceptions,[Exceptional clades whose males lack the usual boreoeutherian scrotum are moles, ]hedgehog
A hedgehog is a spiny mammal of the subfamily Erinaceinae, in the eulipotyphlan family Erinaceidae. There are 17 species of hedgehog in five genera found throughout parts of Europe, Asia, and Africa, and in New Zealand by introduction. The ...
s, pangolin
Pangolins, sometimes known as scaly anteaters, are mammals of the order Pholidota (). The one extant family, the Manidae, has three genera: '' Manis'', '' Phataginus'', and '' Smutsia''. ''Manis'' comprises four species found in Asia, while ' ...
s, some pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant taxon, extant families Odobenidae (whose onl ...
s, rhinoceros
A rhinoceros ( ; ; ; : rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant taxon, extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family (biology), famil ...
es, tapir
Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a Suidae, pig, with a short, prehensile nose trunk (proboscis). Tapirs inhabit jungle and forest regions of South America, South and Centr ...
s, hippopotamus
The hippopotamus (''Hippopotamus amphibius;'' ; : hippopotamuses), often shortened to hippo (: hippos), further qualified as the common hippopotamus, Nile hippopotamus and river hippopotamus, is a large semiaquatic mammal native to sub-Sahar ...
es, and cetacea
Cetacea (; , ) is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively c ...
ns. male boreoeutherians have a scrotum
In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin ...
, an ancestral feature of the clade.
Etymology
The name of this magnorder comes from Ancient Greek
Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...
words:
* () meaning 'north wind
A north wind originates in the north and blows in a southward direction. The wind has had historical and literary significance, since it often signals cold weather and seasonal change in the Northern hemisphere.
Mythology
*In Greek mythology, ...
' or 'the North',
* () meaning 'good', 'right', or 'true',
* and () meaning 'beast'.
Boreoeutherian ancestor
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
The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...
period.Protungulatum
''Protungulatum'' ('first ungulate') is an extinct genus of eutherian mammals within extinct family Protungulatidae, and is possibly one of the earliest known placental mammals in the fossil record, that lived in North America from the Late Cre ...
''[ (''P. coombsi'' about 70.6 to 66.043 Ma., and ''P. gorgun'' about 70.6 to 63.8 Ma.), along side pan-carnivoran species '' Altacreodus magnus'' (about 70.6 to 66.043 Ma.), periptychid species '' Paleoungulatum hooleyi'' (about 70.6 to 66.043 Ma.), and arctocyonid species '' Baioconodon nordicus'' (about 70.6 to 63.8 Ma.).
The ]common ancestor
Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time. According to modern evolutionary biology, all living beings could be descendants of a unique ancestor commonl ...
of Boreoeutheria lived between 107 and 90 million years ago.Genome Research
''Genome Research'' is a peer-reviewed scientific journal published by Cold Spring Harbor Laboratory Press. Disregarding review journals, Genome Research ranks 2nd in the category 'Genetics and Genomics' after Nature Genetics. The focus of the j ...
''.base pairs
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...
.
Classification and phylogeny
Taxonomy
Phylogeny
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.[Frank Zachos (2020.]
"Mammalian Phylogenetics: A Short Overview of Recent Advances"
In book: "Mammals of Europe - Past, Present, and Future" (pp.31-48)[Xue Lv, Jingyang Hu, Yiwen Hu, Yitian Li, Dongming Xu, Oliver A. Ryder, David M. Irwin, Li Yu (2021.]
"Diverse phylogenomic datasets uncover a concordant scenario of laurasiatherian interordinal relationships"
Molecular Phylogenetics and Evolution, Volume 157
See also
* Mammal classification
* Placentalia
Placental mammals ( infraclass Placentalia ) are one of the three extant subdivisions of the class Mammalia, the other two being Monotremata and Marsupialia. Placentalia contains the vast majority of extant mammals, which are partly distingui ...
Notes
References
Additional references
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External links
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{{Taxonbar, from=Q132666
Extant Maastrichtian first appearances