A Warm Body

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• A Warm Body
• Because mammals and birds generate heat within
  their bodies using their metabolism, they are
  endotherms. Other types of chordates (fish,
  amphibians and reptiles) control body
  temperature by behavior. These animals are
  ectotherms.
• 1. Mammals and birds eat much more food than do
  other types of chordates. Why do you think this
  is necessary?
• 2. What are two examples of endotherms? What is
  the specific type of insulation that each one
  has?
• Metabolism is the set of chemical reactions that
  occur in living organisms in order to maintain
  life. These processes allow organisms to grow and
  reproduce, maintain their structures, and respond
  to their environments. Metabolism is usually
  divided into two categories. Catabolism breaks up
  large molecules, for example to harvest energy in
  cellular respiration. Anabolism, on the other
  hand, uses energy to construct components of
  cells such as proteins and nucleic acids.

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Endotherm insulation
Endotherms need to eat a lot of food to fuel
their metabolism.
Tiger - fur
Bird - feathers
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Homeostasis

• The ability to regulate body heat from within is
  an example of homeostasis
• Mammals conserve body heat with external body
  hair and subcutaneous fat
• Mammals rid themselves of excess heat by sweating
  and panting

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Mammals

• Mammals are classified as
• Kingdom animalia
• Phylum chordata
• Subphylum vertebrata
• Class - mammalia

Vertebrata
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Mammal characteristics

• Hair
• Suckle young with milk produced in mammary glands
• Endothermic
• Subcutaneous fat
• Lungs, four-chambered heart and kidneys
• Complex brain
• Internal fertilization
• Complex jaws and teeth
• Most have four legs

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Complex jaws and teeth
CARNIVORE
HERBIVORE
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Lungs
Four chambered heart
Hair or fur
Four legs
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Evolution

• Mammals diverged from ancient reptiles
• Within the mammal class there has been divergent
  and convergent evolution

Reptile ancestor
Divergent evolution within mammals
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Convergent evolution of insect eating mammals
ChinesePangolin
Nine-BandedArmadillo
CommonEchidna
Giant Anteater
Aardvark
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Three groups of mammals based on method of
reproduction

• Order
• Monotremata
• (monotremes)
• lay eggs and
• exhibit features
• of both
• mammals and
• reptiles

Spiny anteater or echidna
Platypus with babies
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Order marsupialia (marsupials) the young
develop in the mothers uterus, but then complete
development in the mothers pouch
http//www.youtube.com/watch?v6xi0x_jGlK4
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12 orders of placentals young develop in
mothers uterus nourished by a placenta
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The placenta supplies the fetus with the blood
supply and nutrients necessary for survival.
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Placentals and their marsupial counterparts
Placental mammals and their marsupial counter- pa
rts