Ocean Discoveries Are Revising Long-Held Truths about Life

Tue, 19 Jul 2022 06:00:00 GMT
Scientific American - Technology

New findings show that the ocean is much more intertwined with our lives than we ever imagined

For more than 50 years deep-sea exploration has been a continuous fount of discoveries that change how we think about life in the ocean, on dry land and even beyond our planet.

In 1977 scientists diving in the restored Alvin made another historic discovery-the first in-person observations of life around hot, hydrothermal vents rising from the seafloor.

Each new ocean discovery that disrupts old dogma reinforces a much larger truth: the ocean is far more complex-and much more intertwined with our own lives-than we ever imagined.

For much of the 20th century, for example, scientists maintained that the deep ocean was a harsh, monotonous place of perpetual darkness, frigid temperatures, limited food and extreme pressure-conditions that should make complex forms of life impossible.

New tools for observing, sensing and sampling the deep ocean, such as increasingly sophisticated underwater vehicles with high-definition camera systems, have demonstrated that biodiversity in the darkest depths may rival that of rain forests and tropical coral reefs.

The rapid three-dimensional change of conditions such as temperature, salinity and oxygen concentration in the deep ocean and the currents and eddies that establish the boundaries of these provinces are expected to fundamentally change as the effects of human activity reach ever farther below the surface.

The greatest paradigm that ocean exploration may tear down is that Earth represents the sole example of life in the universe.

Life might have existed on Mars when it hosted liquid water, and the fact that Earth and Mars have shared ejected material in the past means we could have exchanged the building blocks of life.

The discovery of chemosynthetic life on Earth and the more recent finding of perhaps 13 liquid-water oceans underneath the icy shells of moons such as Jupiter's Europa and Saturn's Enceladus-places that may have been too distant to have shared life-bearing material with Earth in the past-raise the possibility of a second, independent genesis of life.

If life can form twice in one solar system, then it could be anywhere we look in the heavens.