Marine Hydroids

The hydroid Ectopleura larynx is a fouling organism usually found attached to sunken ropes, floating buoys, piers, mussel shells, rocks, seaweed and the undersides of boats in the seas surrounding Great Britain and the Americas.  This organism grows in colonies that can tolerate exposed habitats and strong water currents. Sometimes called Common Flowerheads in the fish farming industry this hydroid can cause problems by reducing water flow and quality.

Hydroid Ectopleura larynx Alexander Semenov/Flickr.com

Ectopleura larynx has two distinct rings of tentacles, one around its mouth and the other at the base of the head. In between these two rings, are the gonophores, or the sexual buds.

Colored scanning electron micrograph (SEM) of the hydroid Ectopleura larynx Credit: Jannicke Wilk-Nielsen/Science Photo Library
SEM of sexual buds of hydroid Ectopleura larynx Credit: Jannicke Wilk-Nielsen/Science Photo Library
Ectopleura larynx has tentacles for defense and feeding. The chemically challenged hydroid in this image is using its tentacles to protect the sexual buds, from an external threat.  Credit: Jannicke Wilk-Nielsen/Science Photo Library

The hydroid Tubularia indivisa is also called oaten pipes. This large hydroid is also native to northeastern Atlantic Ocean, the North Sea, Norwegian Sea and the English Channel.

Hydroid Tubularia indivisa Photo credit: Derek Haslam/Flickr.com
Hydroid Tubularia indivisa Credit: Buiten-Beeld/Alamy Stock Photo

The solitary polps of Hydroid Tubularia indivisa are found on dull yellow unbranched stems that reach a height of 4-6”.   The pinkish to red polps resemble flowers, having two concentric rings of tentacles, with the outer rings being paler and longer than the inner ring.

Hydroid Tubularia indivisa are preyed upon by nudibranch, another marine animal that looks like a snail without a shell.

Nudibranch feeding on Hydroid Tubularia indivisa Credit: Alexander Semenov/Flickr.com

These flower like hydroids are often considered delicate and soft. But beware. Their delicate looks belie their potent nature. They possess an armament of stinging cells equipped in their tentacles to capture and subdue prey.

(SEM) The harpoon-like nematocyst, darting from hydroid Ectopleura larynx, punctures through the hydroid wall, into the prey and releases a toxin that helps immobilize its prey..
Photo Credit: Jannicke Wilk-Nielsen/Science Photo Library

 

 

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Rivers in the Air

Satellite composite image of integrated water vapor showing an atmospheric river impacting the U.S. West Coast.
Satellite composite image of integrated water vapor showing an atmospheric river impacting the U.S. West Coast.

Atmospheric rivers, which can be hundred kilometers wide and stretch across thousands of kilometers from the tropical oceans to the poles, have been known to carry twenty times more water than the Mississippi River. These skyward rivers can release enormous amounts of water given the right conditions. Apart from discharging large volumes of water, the rivers are responsible for some serious weather, including heavy winds, which have been known to cause even more damage than the rainfall itself.

Atmospheric rivers are sinews of moisture from the tropics. The one pictured here appeared over the Northern Pacific on Jan. 3, 2017 Credit: NOAA
Atmospheric rivers are sinews of moisture from the tropics. The one pictured here appeared over the Northern Pacific on Jan. 3, 2017 Credit: NOAA

These “rivers in the air” can be huge, thousands of miles long and 250 to 350 miles wide. They bring rain from the tropic to the rest of the world, which is good, but if they are too strong, they cause floods. If one hits the West Coast it is called a Pineapple Express; while one that hits Louisiana and Texas is called a Mayan Express because you can trace the moisture back to Central America.

A giant atmospheric river hovering over the Mississippi caused flooding in Louisiana and East Texas in March of 2016.
A giant atmospheric river hovering over the Mississippi caused flooding in Louisiana and East Texas in March of 2016.

In February of 2017 the Oroville Dam in Northern California threatened to fail after heavy rainfall due in part to an atmospheric river overflowed Lake Oroville causing officials to open up the emergency spillway.  More than 180,000 people downstream from the Oroville Dam fled after fears of an imminent collapse of the spillway prompted an evacuation order.

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Atmospheric rivers are not restricted to the Pacific Ocean, according to the National Oceanic and Atmospheric Administration. The fact, the rivers move with the weather and are present somewhere on the planet at any given time.

Because atmospheric rivers play such an integral role for water-starved regions, scientists are hoping to lengthen the forecast time and predict the exact areas where the rivers will strike.

 

 

Armored Slugs from the Dawn of Time

Chitons are marine molluscs. They live worldwide, in cold water, warm water, and in the tropics clinging on or under rocks, or in rock crevices. Chitons have a dorsal shell, which is composed of eight separate shell plates. These plates overlap somewhat at the front and back edges, and yet articulate well with one another. Because of this, although the plates provide good protection for impacts from above, they nonetheless permit the chiton to flex upward when needed for locomotion over uneven surfaces, and also allow the animal to slowly.

Chiton from WhidbeyIsland, Washinton. Photo by Kirl L. Onthank
Chiton from WhidbeyIsland, Washinton. Photo by Kirl L. Onthank
 Chiton belly up. Photo by californiabirdy/Getty Images

Chiton belly up. Photo by californiabirdy/Getty Images
Blue-lines chiton from Vancouver Island Photo by Jeff Rotman

Nearly all chitons are grazing herbivores. They scrape algae off of rocks with rows of teeth. Unlike mammalian teeth, which are made primarily of calcium, 160 of a chiton’s 1400 teeth are mineralised with iron. The teeth are located on a conveyor belt-like organ, the radula, with the oldest teeth at the ‘mouth’ end, and with new teeth being constantly produced to replace those worn away whilst feeding. Over its lifetime, from five to 10 years, the chiton uses tens of thousands of teeth.

Chiton mollusc's teeth magnetite Lyle Gordon NW University Evanston IL dn24329-1_800
Lyle Gordon/Northwestern University, Evanston, IL

One species, Chaetopleura apiculata, uses a crazy-looking array of teeth (pictured above) to chew up rocks and extract delicious algae. Derk Joester of Northwestern University is using the critter’s odd, self-sharpening and bulbous teeth as a model for materials that could be used to form better artificial bone. He and his colleagues have studied how organic proteins can direct and support the growth of inorganic, bony tooth minerals.

The teeth of chitons resist cracking because of the highly ordered, submicroscopic architecture that features a partnership between hard mineral crystals and fibers. The wear and crack resistance is interesting because it’s derived from an interactive foursome of carbohydrate, protein, metal ions, and mineral crystal. Magnetite mineral crystals impart the tooth with wear resistance while the carbohydrate, protein, and metal ions organize together to form long, thin fibers imbibed in the mineral crystal; the fibers impart the tooth with crack resistance.

Another scientist, David Kisailus of the University of California, Riverside, is studying a different chiton’s teeth. The gumboot chiton (Cryptochiton stelleri ) largest and most meatloaf-like of the molluscs, has an array of teeth shaped somewhat differently than its cousin’s. But it, too, grinds up rock.

Gumboot chiton belly-up Photo by Brian Good/flickr.com
Gumboot chiton belly-up Photo by Brian Good/flickr.com
Gumboat chiton teeth kisailus-images-chiton_Page_3
Gumboat chiton teeth

Kisailus has found that gumboot chiton teeth contain magnetite as well.  This mineral makes them not only super-strong, but also magnetic.

After studying the process by which magnetite is incorporated into chiton teeth, Kisalius began working on developing a similar mineralization process for materials used in solar cells and lithium-ion batteries — and, perhaps, body armor.

Chitons are armored slugs from the dawn of time, with stones for eyes and magnets for teeth. We’re lucky they’re so slow, small and harmless – I’m pretty sure they only exist as a stern warning to us all of what Mother Nature is capable of.

Over Under Look at a Siphonophorae

(c) Mathew Smith
(c) Mathew Smith

The Portuguese Man o’ War, also known as the Bluebottle, is a jellyfish-like marine invertebrate of the family Physaliidae. Despite its outward appearance, the Man o’ War is not a jellyfish, but a siphonophore. Siphonophorae differ from jellyfish in that they are not actually single creatures, but colonial organisms made up of many minute individuals called zooids. Each of these zooids is highly specialized, and, although structurally similar to other solitary animals, they are attached to one another and physiologically integrated to the extent that they are incapable of independent survival.

Man o’ Wars are found, sometimes in groups of 1,000 or more, floating in warm waters throughout the world’s oceans. They have no independent means of propulsion and either drift on the currents or catch the wind with their gas-filled bladders. To avoid threats on the surface, they can deflate their air bags and briefly submerge.

(c) Mathew Smith
(c) Mathew Smith

Their tentacles can extend 165 feet (50 meters) in length below the surface. They are covered with venom used to paralyze and kill fish and other small creatures. Portuguese Man o’ War are feared by swimmers and surfers because of their painful stings. The pain is caused by the discharge of a large number of stinging cells when the tentacles make contact with your body.

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Bluebottles appear to light up because of a natural process called bioluminescence. It may draw attention to its venomous tentacles to scare off his predator – hungry loggerhead turtles.

Glow caused by bioluminescence.  Photo (c) Mathew Smith
Glow caused by bioluminescence. Photo (c) Mathew Smith
Loggerhead sea turtle preparing to eat Man o' War.  Credit:  Stephen Fink
Loggerhead sea turtle preparing to eat Man of War. Credit: Stephen Fink

One award-winning photographer has braved numerous agonizing encounters to capture these beautiful creatures on film. On numerous occasions the alien-like marine creatures wrapped their tentacles around Mathew Smith’s wrist and neck, which were not covered by his wetsuit. Smith spent 12 months at Bass Point Cove in New South Wales, Australia perfecting an over-underwater technique using a waterproofing camera case with a 45cm wide dome he designed. Through careful lighting, Smith’s iridescent photographs capture marine life in new and luminescent ways.

Photo of Mathew Smith at work by Warren Keelan

Photo of Mathew Smith at work by Warren Keelan

Matthew Smith was last year named Australian Geographic Nature Photographer of the Year and BBC Wildlife Photographer of the Year.

“For me one of the most wondrous parts of any dive is the moment that the water engulfs my mask as my head slips below the surface,” Mr Smith said.

“I think it’s the suspense of the unknown of what lies beneath, and the thought of what alien creatures I might encounter. That is what draws me to taking half-over/half-underwater images. I try to convey to the viewer that majestic feeling in a picture format, to create a window into another universe.”

To see more of Mathew Smith’s amazing work go to

http://www.mattysmithphoto.com

It’s astonishing to realize that the whole coordinated bluebottle creature – which floats, breeds, stings, hauls up and digests – is actually four sub-colonies, in one super-colony, of thousands of animals working together.

(c) Caters News Agency
(c) Caters News Agency