diving

Image from Wikimedia commons https://commons.wikimedia.org/w/index.php?curid=1475156 Until now I had assumed that a "peep" was that squishy sugar-covered marshmallow treat that we enjoyed as kids and a "yo-yo" was a toy on a string. As it turns out, peep and yo-yo are also term used to described types of diving patterns. A square dive is one in which there are no excursions to the surface, known as a "peep", except at the end of the dive, of course. This is in contrast to a yo-yo dive in which divers repeatedly "peep" for a moment at the surface during a dive. The problem is that yo-yo…
Image of hooded seal from NOAA Fisheries (File:Hooded seal.JPG) [Public domain], via Wikimedia Commons Heart rate decreases during diving in seals and other animals. Thus the ascending aorta becomes very important during diving as it helps to maintain blood pressure during prolonged dives. A new study published in the American Journal of Physiology - Regulatory, Integrative and Comparative Physiology was designed to examine the ascending aorta of hooded seals (Cystophora cristata) and the tiny blood vessels that supply nutrients to it, called the vasa vasorum. The ascending aorta of the…
Photographer Jesse Cancelmo was struck by the general lack of understanding of the sea life and ecology of the Gulf of Mexico that became apparent with the big oil spill in 2010, and this inspired him to carry out a major photographic project in the Gulf. He felt many had written off the Gulf as a post-environmental disaster dead zone. While environmental effects in the Gulf are certainly very important, it is still a living, thriving ecosystem, the product of Candelmo's work, Glorious Gulf of Mexico: Life Below the Blue, attests to this. This is a stunning coffee table type book (but…
Image of Steller sea lion by Daniel Hershman from Federal Way, US (A crashing wave) [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)], via Wikimedia Commons Animals exposed to military sonar are thought to develop symptoms similar to decompression sickness. Since microparticles in the blood are known to increase with decompression sickness in diving land animals, researchers explored whether levels were also increased in Steller sea lions (Eumetopias jubatus), that similarly hold their breath while diving. Microparticles are fragments of cell membranes. The research team compared…
The people who owned my mom's summer house in the 60s and 70s threw household waste into the sea from the main dock. And they methodically filled their empty wine bottles with water and sank them there. (If you toss an empty bottle into the sea it floats away.) The water's only about 2.5 m deep at the dock, so when we took over in '82 we could see the junk covering the sea floor clearly. Hundreds of bottles. For a few years in the mid-80s me, my brother and our friends did a lot of diving and took most of the stuff ashore. But a few empties have still been visible in favourable lighting,…
A new book, "The Deep: The Extraordinary Creatures of the Abyss" by Claire Nouvian, a French journalist and film director, reveals haunting images of some of the most bizarre creatures on the globe, ones that live in the deepest parts of the ocean. In many cases the creatures- some of which were photographed as far down as four miles- have never been recorded on film before, and some are still unidentified. The fantastic book contains 220 photographs and scientific information about the living conditions of life miles below the surface. Speculating in the book, Craig M. Young of the Oregon…