Theria and Prototheria makes the most sense because Prototheria avoids confusion with its infraclass / order Monotremata .-- Ingoolemo 06 : 29, 30 May 2004 ( UTC)
12.
Therefore, neither of these states can supply a uniquely shared derived character which would support a'prototherian'grouping of orders in contradistinction to Theria ( Kemp 1983 ).
13.
In some classifications, extant mammals are divided into two subclasses : the Prototheria, that is, the order Monotremata; and the Theria, or the infraclasses Metatheria and Eutheria.
14.
The Prototheria-Theria system is consistent with'evolutionary classification', in which the organisms in a taxon are more closely related to each other than those in other taxa.
15.
Theria Barnes of Musi Furs of Montreal, whose company will begin selling nutria coats nationwide, believes that " nutria is probably at the beginning of a major spiral into the stars ."
16.
"' Holotheria "'are a diverse group of mammals that are descendants of the last common ancestor of " Kuehneotherium " and Theria ( the group that includes marsupials and placental mammals ).
17.
This provides the connexion between the groups and the names of their taxa seen in the pre-Huxley system . ( This particular variant can go even further, using Monotremata-Ditremata, rather than Prototheria-Theria ).
18.
Most morphological evidence supports the theria hypothesis, but one possible exception is a similar pattern of tooth replacement seen in monotremes and marsupials, which originally provided the basis for the competing " marsupionata hypothesis " in which the divergence between monotremes and marsupials happened later than the divergence between these lineages and the placental mammals.
19.
Initially treated as subclasses, Metatheria and Eutheria are by convention now grouped as infraclasses of the subclass Theria, and in more recent proposals have been demoted further ( to cohorts or even magnorders ), as cladistic reappraisals of the relationships between living and fossil mammals have suggested that the Theria itself should be reduced in rank.
20.
Initially treated as subclasses, Metatheria and Eutheria are by convention now grouped as infraclasses of the subclass Theria, and in more recent proposals have been demoted further ( to cohorts or even magnorders ), as cladistic reappraisals of the relationships between living and fossil mammals have suggested that the Theria itself should be reduced in rank.
