Reading 14

This passage is taken from a book entitled Water: The Fate of Our Most Precious Resource by Marq De Villiers (© 1999 by Marq de Villiers).

  1. Where did water come from? The 
  2. most common assumption is that 
  3. the earth itself is around 4.6 billion
  4. years old, formed by gravity from 
  5. cosmic junk, clouds of ionized 
  6. particles around the sun, debris 
  7. left over from the somewhere-
  8. sometime explosion called the Big 
  9. Bang. This cosmic garbage dump
  10. coalesced to form a protoplanet, 
  11. which grew by gravitational attraction 
  12. of even more junk (what the 
  13. cosmologists call “particulates”). 
  14. This was the Hadeon Eon: a sort-of 
  15. Earth existed, but there was no 
  16. atmosphere, no ozone layer, no 
  17. continents, and no oceans – and 
  18. most definitely no life. 
  19. Around half a billion years later, 
  20. give or take an eon or two, things 
  21. had settled down enough to 
  22. precipitate rocks; the oldest known 
  23. rocks are in Greenland, and have 
  24. just celebrated their 3.9 billionth 
  25. birthday. The earth was still aflame 
  26. with volcanoes and bombarded by 
  27. asteroids, meteorites, and whatever 
  28. else was floating in the interstellar 
  29. void and intersecting with our nascent 
  30. planet, but those oldest rocks show 
  31. signs of having been deposited in 
  32. an environment that already 
  33. contained water. There is no direct 
  34. evidence for water for the period 
  35. between 4.6 and 3.8 billions years 
  36. ago. But suddenly, there it is. 
  37. The prevailing theory is that the
  38. atmosphere was created from the
  39. release of gases from volcanic eruptions.
  40. As the eons passed, the first lightweight
  41. silica and aluminum rocks, which are
  42. typical of continental land masses,
  43. formed. The surface of the earth
  44. cooled, and water vapor in this spanking
  45. new atmosphere condensed to form the
  46. water of the oceans. Which begs the
  47. question: Where did the water vapor in
  48. the atmosphere come from in the first
  49. place? What was it in the volcanism
  50. that was our first “weather” that
  51. produced water? Or perhaps it was
  52. already present in all that cosmic
  53. junk – comets, after all, are sometimes
  54. little more than frozen lakes of water –
  55. and it came from space, an alien and
  56. infinitely curious little molecule. For
  57. water is curious, much more curious
  58. than it might at first sight appear,
  59. and is actually little understood. Why
  60. is it, for instance, that water is the
  61. only substance whose solid form is
  62. less dense that its liquid one (a
  63. phenomenon that has profound
  64. implications for aquatic life)?
  65. Scientists have discovered that water
  66. is made up of hexagons of hydrogen
  67. atoms arranged in what is called a
  68. “cage” structure, and that the
  69. smallest theoretical drop of water
  70. is made up of six molecules arranged
  71. as a cage. Which means what? No
  72. one really knows.
  73. In any case, water appeared,
  74. precipitated from what were not
  75. yet called the heavens. Then, around
  76. 2.5 billion years ago, life on earth
  77. began. And it almost certainly began
  78. in water.
  79. Darwin and the early evolutionists
  80. imagined life evolving in a pool of
  81. soupy, chemical- and nutrient-rich
  82. water, an idea still pretty much
  83. accepted today, although there is a
  84. small but influential scientific subset
  85. that believes that life, too, might have
  86. come to us from space, ready formed,
  87. cosmic nuggets among the infinite
  88. dross.
  89. “Runoff collected in a small volume
  90. is the most likely means of achieving
  91. the necessary concentration of
  92. ingredients,” says Gustaf Arrhenius,
  93. a geochemist at the Scripps Institute
  94. of Oceanography. In the dry language
  95. of chemists he writes: “Ponds may
  96. have further concentrated
  97. compounds on the internal
  98. surfaces of sheet-like minerals,
  99. which attract certain molecules
  100. and act as a catalyst in the
  101. subsequent reactions. Two
  102. aldehyde phosphate molecules
  103. thus united form a sugar phosphate,
  104. a possible precursor to organic life”
  105. – as though that explained anything
  106. at all.