5/18 & 5/19 - 7th Grade Agenda

Collect HW: Reading & Notetaking 226 – 228Collect Signed Grade PrintoutAmphibiansClasswork: Design your own speciesVideo: Life (Amphibians & Reptiles)Textbook Reading 486 – 494HW: Reading & Notetaking p.229 - 230

Amphibians evolved from Fish

• Mudskipper Fish (Type of Goby Fish)

• It can live out of water for long periods

• It can breath through its skin just like Amphibians

What are Amphibians?

• The word amphibian means “double life”

• After beginning their lives in water

• Most amphibians spend their adulthood on land

• Returning to water to reproduce.

Life cycle of an Amphibian

Do tadpoles have lungs or gills?

• Gills

Do frogs have lungs or gills?

• Lungs

Salamander Larvae

Some Amphibians are Legless

• sdf• Caecilians

(pronounced seh-SILL-yens)

• No Legs• No scales• Usually Blind

Caecilians Larvae

What are reptiles

• Reptiles are ectothermic

• Has Scales• Lays eggs on land• The ancestors of

reptiles were the first vertebrates adapted to life completely out of water.

Amniotic ShellLets the air in and out and keeps

the embryo moist

Characteristics of Lizards

Can a turtle live outside it’s shell?

• No!• The shell is it’s rib and

backbone.

Characteristics of Mammals

• endothermic vertebrates • four-chambered heart • skin covered with fur or

hair. • Most mammals are born

alive• young mammal is fed

with milk

Do Dolphins have hair?

• Yes. Near their blow holes

• Most of the hair disappear when they get older

What are the function of hair and fur?

• Fur and hair prevent body heat from escaping

• Helps maintain a stable body temperature in cold weather

• Animals in cold regions have thicker coats of fur

When did the first mammals appear?

• About 270 Million years ago

• They were small mouse like animals

• After the dinosaurs disappeared about 65 million years ago, larger mammals evolved

You can tell the type of food mammals eat by its skull & teeth.• What type of food

does this animal eat?

You can tell the type of food mammals eat by its skull & teeth.• What type of food

does this animal eat?

Do some mammals lay eggs?

• Yes.• Monotremes lay eggs:• Two types of

Monotremes are: Spiny Anteaters & Duck billed platypus

What are Marsupials?

• Marsupials are mammals

• The young are born alive

• But at an early stage of development, they develop in a pouch on their mother’s body

Baby Kangaroo in mother’s pouch

What are Placental Mammals?

• Placental mammal develops inside its mother’s body

Diversity of mammals

• Most of the mammal species are bats and rodents