The California Market Squid (Loligo opalescens)
Some of the sweetest machines in North America cruise California Highway 1 in search of smooth concrete curves, tasty waves and picture-perfect California sunsets. To find the sleekest cruisers in Cali, though, you've got to leave the P.C.H. behind. A few hundred yards west, just under the sparkling midnight-blue surface of the mighty Pacific Ocean, the California market squids cruise the Hydro Highway.
These critters have it all. Two ways to ply the depths come standard with Loligo opalescens. First, the paired triangular fins, placed near the aft apex, provide low-speed maneuverability -- perfect for those tight-swimming schooling situations. For the high-speed commute (or dodging those gnarly sea lions) these guys fire up their patented jet propulsion. You've heard all about it, and only cephalopods have it. It ain't the most fuel-efficient way to travel, but yowza, if you need explosive speed, it's your best bet. Zero to...really fast...in a split second! How does it work? It's a trade secret, but here's a glimpse...first, the mantle muscles relax, allowing water to rush into the mantle cavity. Then the squid locks down the mantle-funnel cartilages, aims the funnel and FIRES -- contracting the mantle muscles to blast water out through the funnel. Since every action produces an equal and opposite...you know the story. The squid shoots backward! Heck, who needs a caudal fin?
That ain't all. Two camera-type eyes with pretty much the same design as vertebrate eyes (but better -- the squid's eyes have the photoreceptive cells on the surface of the retina, rather than buried beneath a bunch of wiring at the back of the retina, like vertebrates) give the squid a nearly 360-degree view of its murky underwater world. The front end is packed with eight muscular arms lined on their inner surfaces with tenacious tooth-laden suckers -- perfect for holding those tasty shrimp and fish morsels. To top it all off, these beasts can fire two long tentacles with sucker-packed tips at an unsuspecting crustacean hors d'oeuvre. Score!
Two more nifty features come standard on these beasts. Remember those old spy movies where the good guy's fancy convertible can dump a timely smoke screen to foil those bad guy commies? Say no more. The squids have it covered. A strategically placed ink sac can blow a nasty, slightly intoxicating cloud of ink into an unfriendly fish's face while the squid escapes. And, as if that weren't enough, these animals come equipped with a sophisticated visual communication system that doubles as a cloaking device -- they can alter the pattern (and color, to some extent) of their skin at will, almost instantaneously! Sophisticated neural hardware to control the action is included free of charge. They can use this snazzy set of equipment to communicate their intentions to mates, competitors and potential predators or to almost disappear from view.
Yeah, nice, but it's what they've got inside that counts. Under the hood (or mantle, I should say -- only nautiluses have hoods), Loligo opalescens packs a fully operational closed circulatory system (they aren't just for annelids and chordates anymore), complete with three -- count 'em, THREE -- hearts. That means three times the oomph of the average animal. The main powerhouse, the systemic heart, lies mid-ventrally and pumps the oxygen-packed blood to those powerful mantle muscles, the fins and the rest of the beast's body. On the way back, the blood, now drained of oxygen, drifts toward the pair of gills. Then the twin branchial hearts, one at the base of each gill, kick into action, giving the blood a timely boost into the gills. This is the well-oiled system that powers that fabled jet action.
What more do I need to write? All in all, the California Market Squid is a prime-time, lean and mean dream machine, with lots of features standard in the basic model. Undoubtedly a present and future classic.