If I Had A Hammer(head)

Over the years I’ve heard, and even shared, many theories and points of conjecture to explain the ubiquitous question about hammerhead sharks: what in the name of Poseidon is that headshape for?

Some of the more interesting of the swirling theories included:

  • Increased surface area for sensory organs and enhanced ability to interpret, understand, and respond to their environment and seek out prey.
  • The broad flattened head shape could help them pin down prey like stingrays and skates.
  • Better ability to scent, track, and smell prey.  (Big schnoz means better sense of smell?)

Turns out that the head shape may enhance a sense that we actually share in common with sharks: vision.  Researchers with Florida Atlantic University and Hawaii Institute of Marine Biology conducted a joint study using several members of the overall hammerhead group of sharks and discovered that the broadened head as well as the position of the eyes allows for a large overlap in binocular vision as well as sweeping vertical sightlines and even rearview binocular vision in scalloped hammerheads and the relatively tiny bonnethead.

Rearview binocular vision? Talk about an incredible talent.

All of this translates into phenomenal vision fields that allow these highly specialized sharks to view prey with finely tuned depth perception – quite the advantage for species that sometimes inhabit pelagic areas of big blue water where its difficult to judge distance without visual underwater landmarks.