The importance of our moon and plate tectonics for evolution

Life may be very rare in the universe because
where we do find life (here on Earth, subset Fig 1) we find a planet of just the right size in just the right habitable zone that is attended by a large moon that produces daily tides in the oceans. Those tides keep shorelines and tidal pools changing on a daily basis, along with the light-dark cycle for every rotation of the planet.

The moon also keeps the inner earth molten by producing earth tides.
Over deep time a broiling Earth and its cool floating crust produce continental drift. That produces new environments beyond those that are present between the hot equator and the cold poles. This panoply of new and changing environments together with the islands of isolation they often produce greatly encourages the evolution of life forms that are best suited for the many connected niches.

Ocean and Earth tides were more powerful in the early days
of the Earth-moon system when the two were much closer to one another.

Other planets and moons in the solar system don’t have
the variety of environments found here on Earth, whether on a daily basis, or moving from equator to poles, or from ocean to shoreline to mountain, or from rainy to dry to ice bound, or over deep time. Look around. We’re pretty lucky to be here, wherever we are. Things are different everywhere you look. Other planets don’t have that luxury. Sorry, Mars and Venus.

If life did get a start somewhere out there,
it will not have the opportunity to evolve beyond primordial slime if it starts on an unchanging planet without a big moon. A molten Earth is also responsible for planetary magnetism, which produces Van Allen belts, which protects life forms and keeps the planet from losing its oceans.

Those daily and deep time changes in our planet
made us and every other living thing over deep time. As our planet evolved, so did we, gradually over time. Whatever planetary evolution that continues into our deep time future will continue to evolve new niches and lifeforms that are best suited to fit them.

Here is an article about the moon taking 70 percent of Earth’s crust into orbit
which made plate tectonics possible. It is insightful and well written. And it inspired today’s blogpost: spacedaily.com/news/life-01×1.html