Mammal Evolution and Characteristics

Ace your homework & exams now with Quizwiz!

What are Amniota and when did they first appear?

- Early Carboniferous Period -They are animals with Cleidoic eggs (shelled eggs) -common ancestor of all mammals and reptiles

What are synapsids?

Mammals

What group of muscles do herbivores use to chew?

Masseter

When were most extant families recognized to have existed?

Miocene

What were the first herbaceous/omnivorous mammals called?

Multituburculate

Definition of Edentulate

No permanent teeth

Definition of Edentate

No teeth

When was the great mammal radiation?

Paleocene Epoch of Tertiary period (65 mya)

What are carnassial teeth?

Sectorial shearing teeth (dogs and cats)

What group of muscles do carnivores use to chew?

Temporalis

What is Cementum

The covering root of teeth that allow us to age them

What is the diastema?

The gap between the tooth row, such as in deer

These carnivorous creatures were the first "mammals"

Therapsida

When did mammals first appear on Earth?

Triassic Period

True or false - Walrus tusks are canines

True

True or false: Mammals did evolve from reptiles

True, they shared a common ancestor

What are anapsids?

Turtles

What does diphyodont mean?

Two sets of teeth

Do rodents have open- rooted teeth?

Yes

True or False - Narwhal tusks are canines

False, they are incisors

True or False- Elephant tusks are Canines

False, they are incisors

What are diapsids?

Lizards and Snakes

What animals have Homodont teeth?

-Armadillos, whales

6 Characteristics of modern mammals (REMEMBER - Hairy Enchiladas Make Mrs. Piggy Die)

-Hair -Enucleated blood cells -Mammary glands -Muscular diaphragm -Placenta in Therians (and poorly developed in others) -Dentition

Benefit of soft tissue changes in mammals

-Increased metabolism efficiency -Better food gathering and processing methods -Increased auditory acuity

What makes a mammal jaw different from a reptiles?

-Mammals have an enlarged dentary bone instead of multiple lower jaw bones

What the 2 infraclasses of Theria?

-Metatheria (Marsupials) -Eutheria ("Placental" Mammals)

What are the 3 subclasses of mammals?

-Prototheria (monotremes) -Multituburculate (Extinct) -Theria

Anatomical trends leading to mammals and seperating them from reptiles (REMEMBER- Tigger Didnt Meet Christopher Later Since pooh Fell inTWO Honey)

-Temporal opening enlarged -Dentary bone enlarged -Middle ear resulted from remaining jaw bones -Carpal and tarsal bones reduced -Limbs rotated 90 degrees -Soft palate for breathing while eating -Flexibility increased due to loss of ribs -Two occipital condyles for improved head movement -Heterodont dentition

What were the 3 subcontinants called after the breakup of Pangaea?

-West Godwana -East Godwana -Laurasia

When were most extant orders recognized to have existed?

Eocene

What teeth in marsupials are diphyodont?

Last premolars


Related study sets

SAUNDERS MATERNITY: Diabetes, Postpartum Uterine Problems, Hematoma ad Hemorrhage

View Set

Chapter 8: Experimental Research Review

View Set

Unit 5 - Chapter 12: Developing New Products

View Set

Edapt week 4- lymph and lymphatic vessels

View Set