Jellyfish: A Natural History

by Lisa-ann Gershwin

University of Chicago Press

2016, 224 pages, 8.2 x 9.5 x 1 inches

$27 Buy a copy on Amazon

Five interesting facts I read in the just-released Jellyfish: A Natural History:

1. The deadly box jellyfish is the world’s most venomous animal, and its sting feels like “a splash of boiling oil, searingly hot and indescribably painful.” 2. The immortal jellyfish is just what it sounds like – its cells keep regenerating so that it forever cycles from baby to adult back to baby again. 3. Recently, jellyfish blooms – or swarms – have become denser, are covering much larger areas than ever before, and are “lasting far longer than normal,” due to climate change. 4. Jellyfish can clone themselves, but the replica is so different from the original that it ends up being classified as a separate animal. 5. The giant heart jelly can grow to 165 feet, longer than a blue whale.

And this is nothing. Every page of text in Jellyfish has facts as fascinating as these, woven into a thorough coverage of jellyfish history, biology and ecology. Author Lisa-ann Gershwin, a marine biologist who has discovered over 200 new species of jellyfish, does an excellent job of combining a compelling narrative of 50 different jellyfish with luscious, I-can’t-believe-they’re-real photos. Put this book on your coffee table with caution – you might lose your guests as they submerge themselves into a book that’s as exotic as it is absorbing. Read the rest

This intense slow-motion video, depicting an electric eel jumping from a tank to zap a faux alligator head, accompanies a new scientific paper by Vanderbilt University biologist Kenneth Catania. From Nature:

Catania first spotted the behaviour during earlier laboratory experiments with electric eels (Electrophorus electricus), when they would leap upwards to attack a metal-rimmed net as he was trying to fish them out of their tanks. He analysed it by presenting the eels with carbon rods and aluminium plates at which they struck; the video’s plastic alligator, with its flashing light-emitting diodes that are powered by the eel’s electrocution, is his dramatic demonstration of the effect...

The behaviour allows eels to directly shock their opponents, rather than having their voltage dissipated by water.

It is the first time that this has been recorded in a research paper, Catania says — although he argues that his discovery supports a widely disbelieved observation made more than 200 years ago by the Prussian explorer and naturalist Alexander von Humboldt. In a paper published in 1807, von Humboldt recounted that he had seen South American native fishermen herding horses into a pool of electric eels; the eels would discharge themselves against the horses and could be fished safely when they were exhausted.

According to Catania, there are other mysteries of the electric eels left to be solved, like how it can electrocute another creature without zapping itself in the process.

"Leaping eels electrify threats, supporting Humboldt’s account of a battle with horses" (PNAS)

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Ocean photographer Tim Samuel captured these startling photos of a fish swallowed by a jellyfish off Byron Bay, Australia's Pass Beach.

"(The fish) seemed to be struggling a little bit, as it would swim around, it would try to swim in a straight line but the jellyfish would knock it off course, would send it in little circles or loops," Samuel told CNN. "It was a tough decision, I definitely thought about setting it free, but in the end decided to just let nature run its course."

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About two thousand feet (598 meters) below the Gulf of Mexico off the coast of Louisiana, remotely operated vehicle Hercules encountered a magnificent sperm whale. Read the rest

Sandro Bocci's video of sea creatures, magnified and time-lapsed, is like encountering alien life forms. Read the rest

The photo above, by Kyle McBurnie, won the University of Miami's Rosenstiel School of Marine and Atmospheric Science's 2013 Underwater Photography Contest that's open only to amateurs, defined as "photographers who earn no more than 20 percent of their income from photography." The beautiful beastie is a harbor seal (Phoca vitulina) in a kelp forest at Cortes Bank, about 100 miles west of San Diego, California. Read the rest

This video was made by Henry Kaiser, a musician and research diver who guest blogged here yesterday about the problems caused by thinning sea ice in Antarctica. The film takes you on a tour of McMurdo Station and the research being done there by Gretchen Hoffman of the University of California Santa Barbara.

Kaiser dives for different researchers every year. This year, he's working with Hoffman's team, helping them study the effects of climate change on ocean life. Specifically, Hoffman has Kaiser out collecting Antarctic sea urchins so that her team can extract the animals' sperm and eggs to test the development of sea urchin zygotes in differing conditions of PH and temperature.

There's great footage in here of human life above the ice, and animal life below. It's a bit long, but I recommend taking the time to watch the whole thing.

Video Link Read the rest