Over 40% of people live within 100 km of the coast, yet our understanding of the oceans is limited. Exploring the depths of the sea can be more challenging than venturing into space. Scientists are continuously improving their knowledge, but many ocean mysteries remain unsolved.
1. Why Are Orcas Preying on Great White Sharks?
Off the coast of South Africa, strange events have unfolded. Since 2017, great white sharks have been found washed up with their livers missing. This has led to the suspicion that orcas, specifically a pair known as Port and Starboard, are behind these attacks.
Witnesses have documented these orcas hunting great whites. In a notable incident in May 2022, a drone captured footage of Starboard hunting alongside others. In June 2023, Starboard was seen alone, successfully killing a juvenile great white in just two minutes. The orcas disorient their prey by flipping them onto their backs, then feast on the sharks’ nutrient-rich livers.
This predation leads to significant questions about how it affects the local marine ecosystem. Researchers are puzzled about why orcas began targeting great whites at all. Orcas are known to be specialized hunters. While they have previously hunted other species, the reasons behind their shift in prey remain unclear.
2. Where Did Earth’s Water Come From?
Earth is primarily covered by oceans, making up about 70% of the planet. Yet, the origin of this vast water supply is still a mystery. Scientists have two main theories: Either Earth formed in a water-rich area of space, or the water arrived later through comets and asteroids.
Meteorites could hold the clues to this mystery. Certain types of meteorites contain water, suggesting that impacts from space could have delivered significant amounts of water to our planet. Analyzing these meteorites gives scientists insight into the water’s origins. Many believe that Earth’s water likely came from a mixture of these sources, but the complete picture remains elusive.
3. Who Created the Yonaguni Monument?
The Yonaguni Monument off Japan’s southern coast is a fascinating underwater structure. Discovered in 1986 by a diver, it’s composed of stacked sandstone blocks and unique formations, leading some to speculate it could be the ruins of an ancient civilization.
While some argue it’s human-made, others suggest it’s a natural formation. Scientists have different opinions, with some finding features that resemble an ancient city, while others attribute the structure to natural geological processes. The debate continues, with no definitive conclusion in sight.
4. What Lies Behind Strange Ocean Noises?
The ocean is full of sounds—from animals and natural phenomena to human activities. Yet, some noises remain a mystery. One notable sound, known as the ‘Upsweep,’ has been recorded since 1991. It occurs in a distinct pattern and peaks during certain seasons, but its source is still unknown.
Another mystery noise, called ‘the Ping,’ was reported in the Canadian Arctic in 2016, baffling scientists and military personnel. The cause of this sound also remains unverified. Perhaps the most famous underwater sound is ‘the Bloop,’ detected in 1997. Initially thought to be from a giant creature, it was later revealed to be the noise of an iceberg breaking apart. As climate change accelerates ice melt, we might encounter more of these sounds in the future.
5. What Secrets Does the Seafloor Hold?
While we can map the ocean’s surface, the seafloor remains largely unexplored. Although satellite data provides a general picture, many features remain hidden, including underwater mountains and shipwrecks. The Seabed 2030 project is making efforts to map the ocean floor with high-resolution technology.
Currently, only about 26% of the seabed has been mapped, but advancements in understanding the seafloor can enhance our knowledge of ocean currents, climate change, and tsunami prediction. Recent discoveries have even pointed to ancient seafloors buried deep within the Earth, promising to unlock more secrets about our planet’s history.
6. Where Does All the Plastic Go?
Each year, about eight million tons of plastic enter our oceans. While we see some of it floating, researchers estimate that only a fraction is visible on the surface. The majority of plastic is unaccounted for, making it vital for scientists to understand its fate.
Plastic harms marine life, especially large pieces that entangle sea creatures. However, microplastics, which are tiny particles, have become a bigger concern. Studies have found microplastics in deep-sea organisms and even in the air we breathe, indicating that no part of the ocean is untouched by plastic pollution.
7. Why Do Some Ocean Creatures Glow?
In the dark depths of the ocean, many animals produce light through bioluminescence. This ability has developed independently across various species for different purposes—attracting mates, luring prey, or evading predators. Although it has existed for millions of years, the initial triggers for this ability remain unclear.
Some scientists theorize that bioluminescence evolved as a by-product of metabolic processes in ancient ecosystems with low oxygen levels. This capability has allowed marine life to adapt and thrive in their unique environments.
