Mammals 5 th Grade. *About 4,000 different species. What is a mammal? What characteristics do...

Mammals

5th Grade

*About 4,000 different species. What is a mammal? What characteristics do mammals share?

Characteristics of Mammals

• Endothermic vertebrates

• Skin covered with fur or hair

• Most mammals are born alive

• All mammals breathe with lungs

• Every young mammal is fed with milk produced by organs in its mothers body

Characteristics of Mammals

• Most mammals have teeth

• Their teeth are adapted to chew their food, breaking it into small pieces that make digestion easier.

• Most mammals have teeth with 4 different shapes

Mammal teeth• Teeth with 4 different

shapes: – Incisors –to bite off and

cut food– Canines– pointed teeth

that stab food and tear into it

– Pre-molars & molars have broad, flat upper surfaces for grinding and shredding food

The size, shape, and hardness of a mammal’s teeth reflect its diet

• Ex. carnivores have large and sharp canines

• Ex. herbivores have molars for grinding and mashing plants

Mammal teeth reflect diet

• Lions = carnivores – large canines

• Springbok = herbivores -molars

Lion teeth: large canines used to hold prey while they kill it

Herbivore teeth: rely on pre-molars and molars for grinding and mashing

*Mammals breathe using lungs

• Mammals breathe in and out using a large muscle called the diaphragm

• The diaphragm is located at the bottom of the ribs

• Rib muscles and the diaphragm work together to help a mammal breathe in and out

Diaphragm

Diaphragm

Why do mammals have fur or hair to cover their skin?

• They are endotherms, so they need to keep their internal temperature steady!

• All mammals have fur or hair to help them keep their internal temperatures stable

• Animals that live in cold regions will have more fur than animals from warmer temperatures

What else helps mammals keep conditions stable?

• FAT!

• Mammals have a layer of fat beneath their skin

• Like fur and feathers, FAT is an insulator

Differences in amount of fur/hair often depends on the climate in which an animal lives.

Mammals have a variety of adaptations to allow them to move in more ways than members of any other group of vertebrates

A mammal’s nervous system coordinates its movements.

• Nervous System:

– Receives information about the environment

– Brains of mammals help them learn, remember, and behave in complex ways

– The senses of mammals are highly developed and adapted for the ways a species lives

Examples: Tarsiers have HUGE eyes to allow them to see in the dark

Squirrels learn to use different methods to crack different kinds of nuts, depending on where the weak point in each kind of shell is

located

Bats use a keen sense of hearing to navigate in the dark and catch prey

• http://www.youtube.com/watch?v=gZxLUNHEmPw

Dogs, cats, and bears use their strong sense of smell to catch their prey.

Antelopes can smell approaching predators in time to flee.

Seals can see under water in near darkness. Their long whiskers help them get food by detecting the movements of their prey.