Introduction

Sharks

These ancient fish have earned a reputation of being one of the scariest monsters in the sea.  From such movies as Jaws and Deep Blue Sea, sharks are often viewed as hungry, blood thirsting machines from the deep, dark ocean.  Evolving around 400 years ago, sharks are thought to have evolved from the placoderms, a group of primitive jawed fish.  Today, more than 350 species fill our waters, ranging in size from the less than one foot long dwarf shark to the 50 foot whale shark.  An amazing species, sharks inhibit extreme environments such as the arctic and tropics (Shark Biology).

Current research shows just how important sharks are.  Millions of years of evolution have shaped our planet, and the ocean's ecosystems reflect an important biological development with crucial components.  Sharks are seen as the terrestrial lion and bear--they regulate prey populations by weeding out the weak, unfit and excess.  As a result, "the improve the target species' gene pool, leaving the smarter, stronger individuals to reproduce" (Lemonnick).  Not only do they play an immense role in their environmental niche and food chain, but sharks are practical to a human's purpose as well.  Their cartilage has been used as artificial skin for burn victims, their blood contains anti clogging agents, and their liver oil has also been known to aid in white blood cell production. 

Why Be Scared?

In a Time journal article, Michael D. Lemonnick writes how 'It's humans, not sharks, who are nature's most fearsome predators."  He doesn't blame people for their inherent fear of these dangerous creatures; countless shark attack stories have been ingrained into our minds since childhood.  Lemonnick then goes on to explain how rare it is to be attacked.  "On a bad year, as many as 100 people may be attacked by sharks, and of these only about 15% prove to be fatal."  Although humans have little to fear from sharks, an increasing trend of killing sharks threatens their survivorship and well-being in the ocean.  He quotes that each year around 30 million to 100 million sharks are caught for their delicate meat, fins, and hides.  Not all of the killings are purposeful.  Large tuna boats and other sea liners increase this number to a rough average of 6 million shark deaths to one human fatality.  Unfortunately, only four countries--the US, Australia, New Zealand, and Canada--have implemented any sort of shark protection plan.  The US National Marine Fishers Service's Atlantic shark fishery management plan sets annual quotas, sets laws, and mandates species specific tracking to keep tabs on the decreasing numbers. 
 
 

Morphology & Physiology

Sensory Systems

Ampullae of Lorenzini

ElectroreceptionMechanics 

Electroreception Uses 

Other Animals

For questions, comments, or suggestions, please email Bethany Schott
 

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