Chapter 32-2 Mammals. 32-2 Diversity of Mammals Mammals: Monotremes

Chapter 32-2Mammals

32-2 Diversity of Mammals

Mam

mal

s: M

onot

rem

es

Mammal Classification

Monotremes, egg-layersIncludes duck-billed platypus

& spiny anteater

Monotreme: Egg Layers

Mammal that reproduced by laying eggs

Monotremes are found only in Austria, Tasmania, & New Guinea

Only 3 species of Monotremes are alive today:

Duck-Billed Platypus- Broad, flat tail, (like a

beaver), - rubbery snout (like

the bill of a duck); - webbed front feet for

swimming, but sharp claws on its front & hind feet for digging; body covered with tick brown fur.

Monotremes:

2 Species of Spiny Anteaters

Coarse, brown hair & its back & sides are covered with sharp spines that can erect for defensive purposes when threatened. Mouth located at the end of a long snout, it extends its long, sticky tongue to catch insects.

Monotremes:

Monotremes

Mam

mal

s: M

arsu

pial

s

Mammal Classification

Marsupials, pouched mammalsIncludes Kangaroo, Koala, Opossum

Marsupials

Young have a short period of development within the mothers body, followed by a second period of development inside a pouch made of skin & hair found outside the mothers body

Marsupials

Marsupials

Most Marsupials are found…

In Australia & surrounding islands due to Pangaea

Opossum originated in Mexico

Marsupial Mole

Tasmanian Devil

Koala

Mam

mal

s: P

lace

ntal

Mammal Classification

Placentals (90% of all Mammals)

Placenta is an organ that nourishes the young while inside the uterus (womb)

Gestation, period of time young develops in uterus; ensures offspring are protected from predators & environment

Placental Mammals

Mammals that carry their young inside the uterus until birth

Nourishment takes place inside the uterus through the placenta

Placenta

The placenta also functions in passing oxygen to and removing waste from the developing embryo

95% of all mammals are placental

Eutherians: Placental Mammals

Eutherians: Placental Mammals

Orders of Placental Mammals

Artiodactyla (hoofed, with even number of toes)

Carnivora (specialized

hunters)

Orders of Placental Mammals

Cetacea (adapted to aquatic environment)

Chiroptera (only mammal

with true flight)

Orders of Placental Mammals

Insectivora (includes world’s smallest mammals)

Lagomorpha (includes some of the

fastest runners, with 2 pairs of incisors)

Orders of Placental Mammals

Perissodactyla (hoofed,with odd number of toes)

Primates (superior intelligence,

opposable thumbs)

Orders of Placental Mammals

Proboscidea (trunk-nosed)

Rodentia (largest order,

gnawing incisors)

In placental mammals, nutrients, oxygen, carbon dioxide, and wastes are exchanged efficiently between the embryo and mother through the placenta

This is the type of animal that human beings along with just about the majority of all mammals belong to

Hoofed mammals with an even number of toes on each foot are Artiodactyls

Giraffes along with the rest of the Artiodactyls are grazing animals

Meat-eating predators are Carnivores

Grizzly Bears, like the one showed here, among a few other animals in this family are not completely Carnivorous. When meat is not readily available, they are able to eat plants as well

Dolphins and whales, like this Blue Whale, are called Cetaceans

Cetaceans are carnivorous marine mammals that live and breed in the ocean coming up to the surface only to breathe

The only mammals capable of true flight

Bats feed mainly on nectar, insects, and fruit

Only three species of Bats feed on the blood of other invertebrates

Insectivores have sharp claws and pointy snouts that help them seek all the insects that they like to eat

African Hedgehogs, like the one pictured here, have calm natures and make nice pets

Like Rodents, Lagomorphs are herbivorous. Unlike rodents, they have two pairs of incisor teeth in the upper jaw, and strong back legs which are better adapted for leaping and hopping

A great example of Lagomorphs are Rabbits

Hoofed mammals with an odd number of toes are Perissodactyls

Among the animals in this family are the Rhinoceros, which are very defensive herbivores who blindly charge at whoever or whatever they feel is a threat to their baby

Primates have a highly developed brain and set of complex behaviors unlike any other animal on Earth

Ring-Tailed Lemurs, like the one showed here belong to the Primate family as well as Human Beings

Mammals with trunks are Proboscideans, like this baby Elephant

Many species existed at one time, but now only African and Asian Elephants remain

Capybaras are the largest type of Rodent there is

Like all rodents, they have a single pair of long, curved incisor teeth in their upper and lower jaw

Rodents love gnawing on wood and other tough plant material

Sirenians are herbivorous sea mammals, just like these Manatees

When Columbus first sailed to America and spotted these animals at sea, they were mistaken for mermaids

Three-Banded Armadillos like the one pictured here are Xenarthians

Xenarthians are herbivorous creatures with very simple teeth with no enamel or no teeth at all

Three-Banded Armadillos are the only mammal that can perfectly roll itself into a ball

Copyright Pearson Prentice Hall

Biogeography of Mammals

Convergent Evolution in Mammals

Giant AnteaterAardvark

Common Echidna

Chinese PangolinNine-Banded Armadillo

Copyright Pearson Prentice Hall

32-2 Quiz

Copyright Pearson Prentice Hall

32-2

Most mammals are monotremes. marsupials. placental mammals. placental marsupials.

Copyright Pearson Prentice Hall

32-2

Monotremes are the only group of mammals that lay eggs have hair. feed their young with milk. are endotherms.

Copyright Pearson Prentice Hall

32-2

Rabbits belong to an order of mammals called the cetaceans. lagomorphs. proboscideans. chiroptera.

Copyright Pearson Prentice Hall

32-2

Ant-eating mammals on different continents look similar to each other because they are all a result of divergent evolution. adapted to similar ecological opportunities. recently evolved from a common ancestor. evolved from an ant-eating reptile.

Copyright Pearson Prentice Hall

32-2

What is the function of the placenta?

a. production of milk

b. exchange of materials between fetus and mother

c. digestion of food

d. protection of a young mammal after birth