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Adaptations of a Polarbear

    1. Long, stiff hair between pads of bear's feet:  
    - Protect bear's feet from the cold
    - Provides traction on the ice
    - Help the bear swim in cold, icy water  
    - Also helps to keep bear from slipping on the slippery ice
    - Hair usually shakes free any water or ice formed after swimming
    2. Hollow fur
    - Traps air inside, thus making the bear buoyant in water
    - The layer of air provides insulation between their warm bodies and 
              the cold Arctic air and water
    - Insulation provided is lost when fur is covered with oil
    3. Small and rounded ears
    - Prevents water from entering the bear's ears and freezing their 
              eardrums, u see, big ears, more water!
    - Helps conserve body warmth in sub-zero temperatures
    4. Digging of dens several metres deep
    - Shelter from winds that sweep over the ice in strong gusts, 
              unbroken by trees or vegetation
    5. Light colour of bear's fur provides camouflage against the ice
    - When hunting, bear covers black nose with its paws to hide it
    6. Strong swimmers
    - Polar bears can travel up to a speed of 10 kph
    - Have been known to swim continuously for 100 km
    - Enables them to catch prey
    7. Thick layer of fat (blubber) under skin
    - Up to 11 cm thick
    - Insulates bear from arctic cold
    - Overheating might occur
    - To prevent overheating, the bear moves slowly, resting often
      - Excess heat is released from the body through areas where fur is 
              absent or where blood vessels are close to the skin (eg. muzzle, 
              nose, ears, foot, pads, inner thighs, shoulders)
    - Polar bear swims to cool down on warm days or after physical 
    8. Skin under fur is black
            - This is to ensure that the polar bear has a better heat retention