BERKELEY, California — To a hungry fish on the prowl, the split-second neural processing required to see, track, and gobble up a darting flash of prey is a matter of survival.

To scientists, it’s a window into how our brain coordinates the eye motions that enable us to hit a baseball, sidestep an errant skateboarder, and otherwise make our way in a world full of danger and opportunity.

This process is now better understood, thanks to a team of scientists that imaged the activity of individual neurons in a part of a zebrafish’s brain called the optic tectum. The optic tectum receives signals from the retina, filters them, then sends the signals to other parts of the brain that control motion.

They found that when the fish saw something that resembles prey zipping by, the output neurons in the optic tectum are strongly activated. These output neurons send signals to the rest of the brain — a jolt to spark the fish into action and give chase.

See here for more: http://www.underwatertimes.com/news.php?article_id=56430291081

The Jewel from David R. Andrew on Vimeo.

The underwater world of La Jolla Shores. Music by Johann Sebastian Bach

Under A Golden Sky from David R. Andrew on Vimeo.

Dive Report:

Photos: see Julie’s gorgeous B&W photo of a Fried Egg Jelly above….

Date: 9-16-10

Location: La Jolla Shores/South Wall

Surf: 1-2 ft. negligible

Viz: seemed pretty good, approx. 12-15 ft below 70 ft.

Max Depth: 120 ft.

Mix: 32%/ppo: 1.5

Dive Length: 45 mins

Dive Buddy: Dave H.

Marine Life Observed: numerous Spot Prawns  out on the kelp mats, observed as large fields of glowing  eyes, Sarcastic Fringeheads, Spanish Shawl [1], Strawberry Anemones [1 small clump], Vermilion Rockfish and one absolutely huge Sheephead, wedged back into a large hole at around 115 ft.

Highlights:

–Dave and I waded out from the bathrooms at V. St. through negligible surf to drop down into the canyon and headed south toward the South Wall, opposite the Marine Room restaurant, which is always a treat, which its spectacular striated face, dropping away into the abyss.

–on the way back, came across that mini-cave at around 115 ft. and noted a small clump of Corynactis californica [Strawberry anemone] on the north side, as well as a couple large, Vermilion rockfish patrolling the outside, as well as an unbelievably large Sheephead, who appeared to be hopelessly wedged into the back of the cave, his body seemingly larger than the opening of the hole.  It’s always fun to speculate how these large, male Sheephead get into/out of the openings, which appear much smaller than their body size. One assumes they manage somehow–or there’s a ‘back way’ out somewhere we can’t see. A lone Flabellina iodinea [Spanish Shawl]  provided a neon visual treat on the way back, out all by itself on the sandstone cliffs.

The current Fish ID Panel at La Jolla Shores: Courtesy Friends of La Jolla Shores

Friends of La Jolla Shores announces an open call for underwater photographers to submit their photos for the Fish & Species ID Photo Graphic Panel that will be displayed adjacent to “The Map”® in Kellogg Park, La Jolla Shores.

The photos will be used for identification of each of the 62 fish & species represented by life-sized bronze embeds in “The Map”® and found offshore in the La Jolla Shores Underwater Park & Ecological Reserves.

See here for more information: http://www.examiner.com/scuba-diving-in-san-diego/call-for-photos-the-map-fish-id-panel-at-la-jolla-shores

Video: Courtesy of Into the Drink TV