placental mammal


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Related to placental mammal: marsupial, Carnivora

placental mammal

n.

mammal

an individual of the class Mammalia, a division of vertebrates, including all that possess hair and suckle their young.

eutherian m's
true placental mammals which develop chorion, amnion, yolk sac and allantois, all of which contribute to the placenta. Called also placental mammals.
metatherian m's
marsupials including kangaroos, opossums which are born after a brief period of development and spend a long time being nurtured by the mother, usually in a pouch or marsupium.
placental mammal
see eutherian mammals (above).
prototherian m's
monotremes, the egg-laying mammals.
References in periodicals archive ?
Placental mammals today include humans and all other mammals except those that lay eggs or have pouches (marsupials).
Summary: TEHRAN (FNA)- An international team of scientists has generated the most comprehensive tree of life to date on placental mammals, which are those bearing live young, including bats, rodents, whales and humans.
The groundbreaking six-year research collaboration also produced the most complete picture yet of the evolution of placental mammals, the group that includes humans.
The second clan comprised fossils from the Northern Hemisphere and the placental mammals and marsupials.
Studies with a scanning electron microscope and a laser scanning microscope revealed that the microstructure of the tooth's enamel also resembles that of a placental mammal.
This gene, ZBED6, was previously unknown, but the research team soon discovered that it was unique to the placental mammals, including us humans.
He covers the late Cretaceous nonavian dinosaur record, in the shadow of nonavian dinosaurs, in search of the most ancient Eutherian ancestors of placental mammals, patterns and causes of extinction at the K/T boundary, and when and whence mammals after the impact.
Evolution of island mammals; adaptation and extinction of placental mammals on islands.
Researchers found brain size in marsupials and placental mammals correlated with length of maternal care.
This had to occur after the time of the common ancestor of mammals and birds/reptiles (310 million years ago), and before the time of the common ancestor of placental mammals and marsupials (eutherians; 145 million years ago), because both placental mammals and marsupials have XY sex determination with SRY determining maleness.
This applies to all convergencies such as those between marsupial and placental mammals as well as between African and American succulent plants.