Dive into the watery world of sharks & more

How many times this seashore season have you heard someone mention Jaws . . . again?  Or talk up merely being near blue water, or extol the healing properties of salt water?  Add to that liquidy mix this summer’s excess of  wet weather, and you’ve got good reason to think about watery creatures.

When you think of animal life in water, sharks probably come to mind early and often.  So let’s start there, and go way back to earlier shark life — an existence that almost vanished  forever yet still limited the array of sharks even now.   

These days, the worst that can happen to sharks is overfishing and man-made killings, like finning – the barbaric practice of catching sharks only to cut off their fins for shark fin soup, then to toss them back into the ocean.  There, the helpless sharks die of suffocation, blood loss or predation.  

“Humans kill 100 million sharks annually,” according to Humane Society International, with hundreds of millions killed for shark fin soup alone.  https://tinyurl.com/vehx4pup

                      Great white shark                NYT image          

About 19 million years ago, long after dinosaurs were wiped out, sharks nearly went extinct, and even now, they’re still not fully back.  Exactly what happened then is still not known, but a mysterious mass extinction occurred in the world’s oceans that decimated sharks’ diversity.

Scientists studying “dermal denticles,” the microscopic scales that entirely cover sharks’ bodies like protective armor, found in sediment cores that shark diversity had so declined that only a fraction of shark species survived that event.

And now, sharks’ abundance is severely threatened, making for a double whammy that some believe may ultimately amount to the worst extinction of all.  https://tinyurl.com/3eyr293m

Scalloped hammerhead sharks

“Shark attacks” -- or those two words, anyway – are disappearing.  That’s because shark scientists hope to change how people regard sharks: not as blood-thirsty predators, but as animals “whose population has plummeted by 71 % since 1970,” mostly from overfishing.   

One shark expert put it: “A lot of what’s called a shark attack . . . is actually provoked by humans” – plus: the great majority of person-shark meetings don’t involve a bite.   So the suggested alternative wording is preferable because it’s less sensational and more accurate.  For instance, “shark incident” or shark interaction" or "shark encounter."

This fascinating story includes examples of myriad possible “shark interactions,” including when a person accidentally steps on a tiny one or a passing shark touches a person and keeps going. (Remember, sharks don’t know what humans are!)   https://tinyurl.com/3t5adnfp

Whale shark

Time out on sharks for awhile.  Maybe later, dogfish sharks and ghost sharks, from among the more than 500 shark species: small and colossal, glowing and roaming, according to one source.

On to another watery creature I’ve never seen but recently read about: the cuttlefish.  This cephalopod (seh·fuh·luh·paad) has lately become a lab darling for curious (aren’t they all?) scientists.  But first,

A cuttlefish is one member of the molluscan class Cephalopoda that also includes squid, octopus and nautilus.  These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot. --Wikipedia

Ranging in size from about an inch to more than 2 feet, cuttlefish boast one of the largest brains among invertebrates.  They can regenerate their limbs and camouflage, blending with their environment to hunt or escape, and they possess amazing skin that can mimic surrounding textures and colors.  These attributes make cuttlefish attractive for exploring how and when intelligence evolves.  https://tinyurl.com/3xe3vd8c

Cuttlefish competing for a female

Feeling like a nice dip in the ocean about now?  Or would “high and dry” be your destination choice?

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