full transcript
"From the Ted Talk by Gillian Gibb: Why can't some birds fly?"

Unscramble the Blue Letters

Though the common ancestor of all modern birds could fly, many different bird sceeips have independently lost their flight. Flight can have incredible bteneifs, especially for escaping predators, hnnitug, and traveling long distances. But it also has high costs: it consumes huge amounts of energy and limtis body size and weight. A bird that doesn’t fly cevsornes energy, so it may be able to survive on a scarcer or less nutrient-rich food source than one that flies. The Takahe of New Zealand, for example, lveis almost entirely on the soft base of alpine grasses. For bdris that nest or feed on the ground, this predisposition to flightlessness can be even stronger.

Open Cloze

Though the common ancestor of all modern birds could fly, many different bird _______ have independently lost their flight. Flight can have incredible ________, especially for escaping predators, _______, and traveling long distances. But it also has high costs: it consumes huge amounts of energy and ______ body size and weight. A bird that doesn’t fly _________ energy, so it may be able to survive on a scarcer or less nutrient-rich food source than one that flies. The Takahe of New Zealand, for example, _____ almost entirely on the soft base of alpine grasses. For _____ that nest or feed on the ground, this predisposition to flightlessness can be even stronger.

Solution

  1. limits
  2. species
  3. conserves
  4. birds
  5. benefits
  6. lives
  7. hunting

Original Text

Though the common ancestor of all modern birds could fly, many different bird species have independently lost their flight. Flight can have incredible benefits, especially for escaping predators, hunting, and traveling long distances. But it also has high costs: it consumes huge amounts of energy and limits body size and weight. A bird that doesn’t fly conserves energy, so it may be able to survive on a scarcer or less nutrient-rich food source than one that flies. The Takahe of New Zealand, for example, lives almost entirely on the soft base of alpine grasses. For birds that nest or feed on the ground, this predisposition to flightlessness can be even stronger.

ngrams of length 2

collocation frequency
bird species 4
flightless birds 3

Important Words

  1. alpine
  2. amounts
  3. ancestor
  4. base
  5. benefits
  6. bird
  7. birds
  8. body
  9. common
  10. conserves
  11. consumes
  12. distances
  13. energy
  14. escaping
  15. feed
  16. flies
  17. flight
  18. flightlessness
  19. fly
  20. food
  21. grasses
  22. ground
  23. high
  24. huge
  25. hunting
  26. incredible
  27. independently
  28. limits
  29. lives
  30. long
  31. lost
  32. modern
  33. nest
  34. predators
  35. predisposition
  36. scarcer
  37. size
  38. soft
  39. source
  40. species
  41. stronger
  42. survive
  43. takahe
  44. traveling
  45. weight
  46. zealand