Great White Sharks Can Sense Emotions?
Great White Sharks are some of the most remarkable animals on planet earth. Next, our journey continues as we propel ourselves beyond the economics of fear toward more fascinating discoveries as it relates to the shark's advanced biological senses.
The most well-known shark species, such as the great white shark, tiger shark, blue shark, mako shark, and the hammerhead shark, are considered to be apex predators at the top of their underwater food chain.
As apex predators, sharks play a vital role in our ocean's food chain and yet humanity in recent times has brutally obstructed their ability to play this role. Why? First, let's take a look at scientific discoveries on sharks and Great White Sharks in particular.
Built to survive the ocean life
Under a broad definition, it has been recognized that sharks have existed for more than 450 million years. It is estimated that they have since branched out into over 470 species and have been identified as the sister group to the rays.
They can be found in all seas and are common at depths of 2,000 m (7,000 ft.), but are mostly absent below 3,000 m (10,000 ft).
Not like the movie "Jaws" - highly social
A common assumption is that sharks are solitary hunters who simply travel the oceans in search of food. However, this description of sharks applies to only a few species.
Of particular relevance to this article, Great White Sharks can be highly social and remain in large schools from birth. They also display curiosity and play-like behavior in the wild.
Interestingly, sharks struggle to live in captivity and until recently few sharks had ever survived in public aquariums beyond one year. They are often quickly released because they refuse to eat and cannot stand the effects of confinement in public aquariums. Much like an autistic child, the Great White Shark will attempt self-harm by uncontrollably banging its head against the pool walls in attempt to commit suicide.
While previous mainstream movies have framed sharks as simple, reckless and violent creatures, the truth is really nothing like that. They are extremely advanced fish with unique capabilities and wisdom.
Ampullae of Lorenzini - sensitivity to electric fields
Sharks have amazing sensors that can pick up electric signals emitted by all living animals in the water. This is also known as passive electrolocation. The Great White Shark can sense frequencies in the range of 25 to 50 Hz and if close enough, it can detect even a faint electrical heart pulse.
The sensor organs responsible for this ability are called the Ampullae of Lorenzini. While they were first discovered by Marcello Malpighi in 1663, it was in 1678 that Stephano Lorenzini provided a more detailed description.
The system consists of hundreds or thousands of pores on the shark's head that are big enough to see with the naked eye. Each canal leads to a small gel-filled chamber "ampullas," which are lined with nerve cells. These cells are likely used as an internal compass, helping them follow the Earth's magnetic field to travel across hundreds or thousands of miles of open water.
Can Great White Sharks sense a human's brain wave activities in water?
In 1924, German neurologist Hans Berger discovered a way to read brain waves by developing what's known as an electroencephalograph (EEG). And, soon after starting his research, Berger noticed that the electrical activity of each brain wave is correlated to a person's emotional state of mind.
Since sharks have been measured to sense frequencies between 25Hz and 50Hz, which are also related to the emotional status of anxiety and fear, could sharks also feel these brain waves in proximity?
In the Great White Shark 3D movie that plays at IMAX theaters, free-diver William Winram says he believes sharks can pick up on a person's anxiety and fear, and that is what often triggers an aggressive response. Winram observed this sensation while tagging Great White Sharks for scientific research by holding his breath and free diving with them. You can find many videos on YouTube in which he calmly swims alongside Great White Sharks, without fear, anxiety nor incident. This would seem to be a very interesting question for future scientist to pursue.
Great White Sharks: Human interactions
Between 2001 and 2006, the number of human fatalities from unprovoked shark attacks has averaged 4.3 per year globally. Further, it is recognized that most attacks occur during their hunting season. Therefore, it is advisable not to swim in shark-populated areas during hunting season.
Meanwhile, humans are responsible for alarmingly depleting shark populations in our oceans. Based on the analysis of average shark weights, it has been estimated that we are responsible for nearly 100-million shark deaths in 2000, and about 97-million in 2010.
While some species have declined by 90%, it has been estimated that over the past decades the overall population has declined by ~70%. This is both shocking and unsustainable.
Shark fin soup - introducing WildAid's public awareness campaign
At the present time, most sharks are killed for shark fin soup. Shark fins have become a major trade in black markets all over the world. Fishermen capture live sharks, fin them with a hot metal blade and dump the remaining 98% of the animal back into the water. The immobile shark soon dies from suffocation or predators.
In many Asian countries, those in the rising middle classes see shark fin soup as a status symbol. As such, a fear of social rejection drives demand in China.
In response to this issue, global icons like Yao Ming are working with conservation groups such as WildAid to engage the Asian consumers in dialogue and to help awaken them to the ignorance of their actions. Check out their website and videos.
The importance of facing new realities and the limits of specialization
So why do we obstruct and interfere with Great White Sharks? I'll suggest that many leaders, older workers and younger apprentices that work in this shark-finning culture (and all related industries who oppose deterring legislation), are fearful that given their specialized business practices and our highly specialized society, they will find themselves without work and unable to transfer their specialized skills to other industries. Their industry is now an economic bubble set to collapse, which does not provide long-term solutions for the people who work in the industry. There are few paths to regenerating job skills and few economic solutions for the hardships of the many who will be unemployed when there are no more sharks left to fin.
This is the limit of specialization. Authorities must not only legislate this industry but also provide better alternative paths for those involved to acquire more transferable skills.
So, we have a new reality and our past view of Great White Sharks has been proven to be completely incorrect. Now we must face the understanding that the fallacy of all our global fears has supported a global shark finning industry that is now completely out of control.
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