In the past two parts of this series I described how liquid
water is living water, its special chemistry shaping geology and biology to
give us the world today. Water’s life-giving power extends even deeper than
this, as deep as a few billion years back in time. We saw how liquid water’s
chemical power created the Puget Sound and sustains deep-sea ecosystems today.
Likewise, water could have participated in creation long ago.
The chemical ingredients life needs come together at the
deep ocean vents: carbon, sulfur, hydrogen, iron, nickel, and especially energy
from within the earth. Long ago, water’s
chemical power may have brought these ingredients together to shape the first
life forms.
I once avoided these ideas because I felt that a chemical bridge
from non-life to life threatened God’s creative sovereignty. But now I’ve
changed my mind. If God came up with the ideas, then they actually convey God’s creative sovereignty. The
more I appreciate the dynamic elegance of water’s chemistry, the more I think
that God appreciates dynamic elegance, too. All origin of life experiments have
an important role for the chemical power of flowing, liquid water.
For example, some deep-sea vents form rocks with holes that look
suspiciously like small cells. These cavities naturally stockpile and separate chemicals,
like natural laboratories with billions of chambers. They are lined with iron
and nickel atoms that react with the sulfur and hydrogen streaming out of the
earth like Champagne bubbles.
One of the central molecules in all metabolism, pyruvate,
forms spontaneously in these vents, as well as other related molecules that
look like the breakdown products of pyruvate found in every cell. It’s as if a
biochemical network is budding from the rocks. The holes in the rock can hold different
mixtures of chemicals in place, like the 96-well plates scientists use to run
96 experiments at once. In the rock, simple circular chemical cycles could have
formed and started to turn, fed by gas bubbles.
Or maybe the heat was more gentle, the toasty temperature of
a hot spring at the earth’s surface. This makes a different kind of natural
laboratory, where holes in the rock act as gas condensers, collecting steam and
letting it drip down in a purifying cycle. Every organic chemistry lab contains
complex glass sculptures built to condense and distill. Some hot springs have
rocks that do the same chemistry.
Experiments in a similar environment found conditions where
simple 4- or 5-atom molecules naturally rearrange into the complex, three-part
nucleosides that make up DNA. In an elegant flourish, this fascinating set of
reactions is catalyzed, not by a rare element or molecule, but by the very common
bio-molecule, phosphate. DNA has phosphate in it, meaning this important
molecule may incorporate its own catalyst.
Origin of life chemistry as a field is full of successes
like these but also its fair share of failures. One major failure is summed up
by Steven Benner as “the asphalt problem”: undirected reactions tend to make
tar. What’s interesting to me is where the failures may come from. I think most
experiments were too simple, too purified, and too dilute. If the experiments
are made dirtier, in many cases with actual “dirt,” they work better. The deep-sea
experiment above can’t make pyruvate without the iron and nickel from rocks. In
the DNA-making experiment, the DNA nucleosides are not made from a sequence of
reactions, but by mixing everything together in one pot and running thousands
of reactions at once. The more the experimental conditions mimic the geological
complexity of the early earth, the more the resulting chemicals look like biological
complexity (that is, pyruvate or DNA nucleosides).
This experiment is run with chemical ingredients provided by
the periodic table and the physical forces of mixing and geology, which are
mediated by liquid, living water. If God gave the chemical laws, then God gave
water this power, and this could be how God created. God works with me
patiently and through the world around me – perhaps he did the same at the
creation of life.
If we can imagine God giving his power to God’s creation,
then origin of life chemistry experiments have no necessary conflict with a
strong theology of creation. The first biochemical cycles would have obeyed the
rules of chemistry, and we know Who made those rules. Even the deepest part of
the sea at the far extent of Earth’s history is part of God’s creation and ordered
by God’s Word.
Water is the medium of life-giving grace, and we can see
through it to the one who ordered the atoms with the rules of chemical bonding
(and the math that sets those rules). In Greek, such rules would be called the logos -- the wisdom and Word by which
worlds were created. As a chemist, I am called to seek out the subset of those
rules called chemistry, and to understand that God is at work providing and upholding them.
The world looks different if flowing, living water is seen
as a chemical gifted with the potential to create life. We know water is
powerful enough to carve landscapes, form gemstones and ores, and support fantastic
microbes. Now to these powers is added the ability to make life by reacting
with rocks, and the story of creation becomes that much more amazing.
The length of this story is incomprehensible to our small experience.
Our experiments show that Earth held an ocean of life-sustaining water on its
surface for 4 billion years, not boiling it into steam like Venus or losing it
to a barrage of asteroid impacts, like Mars. The word for that duration of
constancy is faithfulness. Through eons, God
has cared for us by upholding a universe with constant chemical laws, rules
that convey the simple grace of living water.
I am writing a book
that recounts the story of these chemical laws, this logos, that shaped the world around us. Water is so important to
that story that I changed the book’s title halfway through to give water a place of
honor – now it is called River of Life:
How Chemistry Shaped Biology. A river is living water, and water, despite
its small size, is the chemical cornerstone of life.
The angle of science and the angle of theology fit together and
co-illuminate in the story of “living water.” The creator who emptied himself of
power and became so small at Christmas also made the small but powerful molecule
H2O, then gave us oceans of it. The more things we discover about
that molecule, the more we can delight in the hand that gave it yesterday and
continues to give it today.
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