This is the period where Mammalia emerged, survived by three lineages - Montremata, Metatherians, and Eutherians.
What is the Jurassic period?
Metatherians and Eutherians originated on these separate continents.
What is North America and Asia?
This is the period when crown-group Eutheria originated.
What is the Cretaceous period?
Eulipotyphla are the most basal (closest to the most recent common ancestor) order in this clade.
What is Laurasiatheria?
These are the teeth that make up the carnassial pair in Carnivorans.
What is the upper 4th premolar and lower 1st molar?
Crown-group Mammalia is divided into two clades: Australosphenida and Boreosphenida. Name the descendants in each clade and their continent of origin.
Monotremes in Gondwana, Therians in Laurasia.
This bone provides extra support in the pectoral girdle of some extant mammals, but is lost in some cursorial species.
What is the clavicle?
This model of diversification is the most widely-accepted model of placentalia diversification.
What is the long-fuse model?
This body opening is considered a pleisiomorphic trait within Eulipotyphla.
What is the cloaca?
These two orders make up the megaorder Ferae.
What is Pholidota and Carnivora?
These are the two jaw joints that originated in cynodonts and contributed to the mammalia middle ear.
What is the quadrate-articular and dentary-squamosal joint?
What is supination and pronation?
In early Cenozoic mammals, body size was increasing following an increase in this element.
What is atmospheric O2?
Chiroptera are the most diverse of all mammal orders, yet not much is known about how they came to be - due to a lack of this "stone" cold evidence.
What is a transition fossil?
This key synapomorphy among Fera aids in stability of the forelimbs.
What is the scapholunar bone?
These two Mammalia groups are born with the Q-A joint and don't develop the D-Sq joint until later in life.
What are the Monotremes and Metatherians?
In the tribosphenic molar, this is the point on the upper molar and the basin on the lower molar - it facilitates crushing and grinding.
What is the protocone and talonid basin?
Marsupials and Xenarthra originated on this continent, then dispersed via landbridges.
What is South America?
The evolutionary success of Chiroptera is attributed to these two traits, both used in foraging.
What is echolocation and powered flight?
These are the two suborders within Carnivora, distinguished by differences in rostrum length and teeth specialization.
What is Caniformia and Feliformia?
This vision trait evolved after montremes and therians diverged.
What is nocturnal vision?
This reproductive method evolved only once in therians.
What is matrophic viviparity?
The mammal placenta is derived from these two extraembryonic membranes fusing.
What is the chorion and yolk sac?
Microchiroptera is a sub-group that encompasses small carnivorous bats that use echolocation. These are three traits the describe the subgroup Megachiroptera.
Large size, fruit-eating, non-echolocating.
What is hypsodont teeth?