Week 2: "Of Feathers, Fat, & Freezing"

Advanced English Online Winter 2021
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definitions & notes only words
  1. thermostat
    a regulator for automatically regulating temperature
    Once settled, they lower their body temperature, just as we lower the thermostat in our houses to save energy a night.
  2. calorie
    unit of heat raising 1 gram of water by 1 degree centigrade
    The higher the fat content the better, since calories – the units of energy in food – are concentrated in fats.
  3. cache
    a hidden storage space
    After most of the other birds have flown south to warmer climates, chickadees return to their caches.
  4. forage
    collect or look around for, as food
    As the days shorten, the temperature drops, and since chickadees forage only during daylight hours, they have the least amount of time to eat during the season when they need the most fuel.
  5. stock
    a supply of something available for future use
    They also seek out wintering insects between the cracks in the tree bark and feast at bird feeders stocked with fatty treats like sunflower seeds, peanut butter, or mealworms.
  6. insulation
    reduction of the transmission of sound, heat, or electricity
    Feathers are the perfect insulation, trapping air between them and acting as a barrier between the cold outdoor weather and the birds’ bodies.
  7. morsel
    a small amount of solid food; a mouthful
    They stash away bugs, seeds, or fat from dead animals, tucking these morsels into crevices in tree bark.
  8. plunge
    dash violently or with great speed or impetuosity
    Chickadees living near Fairbanks, in interior Alaska, experience -30° to -40°F on a regular basis, with temperatures sometimes plunging to -60°F or colder.
  9. concentrated
    gathered together or made less diffuse
    The higher the fat content the better, since calories – the units of energy in food – are concentrated in fats.
  10. bitterly
    extremely and sharply
    Although fragile in many ways, the tiny chickadee shows how tough it really is by surviving the bitterly cold winters of northern North America.
  11. frigid
    extremely cold
    But even such energy efficiency by itself is not enough to survive the frigid winter days.
  12. cram
    crowd or pack to capacity
    As darkness falls, they cram themselves into little hollows in the trees.
  13. reserve
    hold back or set aside, especially for future use
    By lowering their body temperature, or “thermostat”, by nearly 20°F, their fat reserves last longer, enabling them to withstand the cold until it’s light enough to forage again.
  14. hypothermia
    subnormal body temperature
    For humans, becoming hypothermic (having lower body temperature) like this would be deadly, but chickadees use hypothermia to their advantage.
  15. warm up
    rise in temperature
    Then, when this blood returns to the main part of the body, it is warmed up again as it passes the warm blood entering the legs.
  16. feather
    a light growth that makes up the covering of a bird's body
    Like all birds, chickadees have feathers, so in a sense, they wear little down parkas all the time.
  17. store
    keep or lay aside for future use
    Since they don’t have a way to store food to eat later, they must eat enough each day to survive the long, 18-hour night.
  18. fuel
    a substance that can be consumed to produce energy
    In the same way that we must burn more fuel in the winter to keep our houses war, chickadees also need more fuel to stay warm.
  19. feast
    a ceremonial dinner party for many people
    They also seek out wintering insects between the cracks in the tree bark and feast at bird feeders stocked with fatty treats like sunflower seeds, peanut butter, or mealworms.
  20. survive
    continue in existence after
    But even such energy efficiency by itself is not enough to survive the frigid winter days.
Created on January 5, 2021 (updated January 5, 2021)

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