Survivors: Intertidal Zonation
An organism's preference for the habitat to which it is adapted creates a mosaic of similarly adapted organisms clumped in recognizable bands along the shore. This is a phenomenon known as intertidal zonation.
Survivors: Long-Term Survivors
Despite the challenges of long-term survival on Earth, some phyla-including sponges, jellyfish, arthropods and mollusks-have endured for hundreds of millions of years, even in the most extreme environments.
Survivors: Predators and Prey
The ocean provides home to a dazzling variety of life. Yet there was a time when early life forms faced a multitude of struggles that threatened their ability to survive. The evolution of adaptations to overcome these ch..
Survivors: Survival in the Intertidal Zone
Perhaps nowhere on Earth is the ability to survive better demonstrated than that part of the shore alternately exposed and submerged by tides-a region known as the intertidal zone. Remarkably, marine organisms there have..
Survivors: The Oxygen Revolution
At one time, Earth's atmosphere had a far smaller percentage of oxygen than it does today. Only when that percentage began to rise, thanks to the oxygen production of photosynthetic plants and organisms, was it possible ..
Temperature and the Velocity of Sound
Renowned oceanographer and geophysicist Walter Munk talks about the relationship between temperature and the velocity of sound, observing that velocity increases with temperature. Because temperature generally increases ..
The Dynamic Theory of the Tides
Renowned oceanographer and geophysicist Walter Munk talks about the dynamic theory of the tides, noting that Sir Isaac Newton's theory of the tides was incomplete. French scientist Pierre-Simon Laplace explained a centur..
The Heard Island Test and Climate Change
Renowned oceanographer and geophysicist Walter Munk talks about efforts to measure ocean warming through sound in a test done near Heard Island, an area considered unique because sound emanating from that point can theor..
The Moon, The Sun and Tides
Renowned oceanographer and geophysicist Walter Munk talks about the relative roles of the Sun and the Moon in tidal processes. He observes that, over time, the Moon is moving further away from the Earth. While the gravit..
The Ocean as a Sound Channel
Renowned oceanographer and geophysicist Walter Munk talks about differences in the ways sound travels in the ocean as compared to through the air. He observes that the ocean is an ideal medium through which sound can tra..