HUMANS AND THE OCEANS
seal clothing Our ocean and coasts affect us all — even those of us who don't live near the shoreline. Consider the economy. Through the fishing and boating industry, tourism and recreation, and ocean transport, our coastal and marine waters support millions of jobs. Consumers spend over billions annually for fishery products. Then there's travel and tourism. Our beaches are a top destination, attracting millions of people a year. [Source: NOAA]
A study by American, Canadian and British researchers in the mid 2000s revealed that not a single square meter of sea water has been left untouched by human activity and 41 percent of the seas have been negatively affected by polluted runoff, overfishing and other abuses. Not surprisingly some of the most affected areas are near the shorelines where many people live (half the world’s population lives near the sea). Here scientists have found huge dead zones — like one off of Oregon that spread northward to Washington and southward to California — that robbed many sea creatures of oxygen.
The consequences are often global and the solutions are often global as well. But because much of area that is affected is beyond the borders of countries it is difficult to get nations to work together to tackle the problems.
A report published in the journal Science in November 2004 warned that if current trends of overfishing and pollution continue the population of almost every kind of sea food could collapse by 2048. The lead author the report, Boris Worm of Dalhousie University in Halifax, Canada, told Reuters, “Whether we looked at tidal pools or studies over the entire world’s oceans, we saw the same picture emerging. In losing species we lose the productivity and stability of entire ecosystems. I was shocked and disturbed by how consistent trends are — beyond anything we suspected.” Worm’s team spent four years analyzing 32 controlled experiments, other studies from 48 marine protected areas and global catch data from the United Nations Food and Agriculture Organization of all fish and vertebrates from 1950 to 2003.
Worm said, “At this point 29 percent of fish and seafood species have collapsed — that is their catch has declined by 90 percent. It is a very clear trend, and it is accelerating. If the long term trend continues, all fish and seafood species are projected to collapse..It looks grim and the projection of the trend into the future looks even grimmer. Scientists at the U.S. National Marine Fisheries Service and people in the fishing industry find some of the predictions to be too pessimistic and say progress is being made remedying practices that were not sustainable.
Book: “The Unnatural History of the Sea” by Callum Roberts (Island Press, 2009). Roberts is a professor of marine conservation at the University of York in England.
Websites and Resources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; “Introduction to Physical Oceanography” by Robert Stewart , Texas A&M University, 2008 uv.es/hegigui/Kasper ; Fishbase fishbase.se ; Encyclopedia of Life eol.org ; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; Woods Hole Oceanographic Institute whoi.edu ; Cousteau Society cousteau.org ; Monterey Bay Aquarium montereybayaquarium.org ; MarineBio marinebio.org/oceans/creatures
Seasickness and What Happens If You Drink Seawater
Drinking seawater can be deadly to humans. Seawater contains salt. When humans drink seawater, their cells are thus taking in water and salt. While humans can safely ingest small amounts of salt, the salt content in seawater is much higher than what can be processed by the human body. Additionally, when we consume salt as part of our daily diets, we also drink liquids, which help to dilute the salt and keep it at a healthy level. Living cells do depend on sodium chloride (salt) to maintain the body’s chemical balances and reactions; however, too much sodium can be deadly. Human kidneys can only make urine that is less salty than salt water. Therefore, to get rid of all the excess salt taken in by drinking seawater, you have to urinate more water than you drank. Eventually, you die of dehydration even as you become thirstier. [Source: NOAA]
One of the least pleasant aspects of going to sea is the possibility of getting seasick. Sometimes it can be quite unpleasant. Mark Twain said: “At first you are so sick you are afraid you will die, and then you are so sick you are afraid you won’t”. An individual's susceptibility to seasickness is highly variable. If you've ever had motion sickness when traveling by car, plane, or amusement park ride, you may be more susceptible to seasickness while aboard a vessel.
Seasickness is a result of a conflict in the inner ear, where the human balance mechanism resides, and is caused by a vessel’s erratic motion on the water. Inside the cabin of a rocking boat, for example, the inner ear detects changes in both up-and-down and side-to-side acceleration as one’s body bobs along with the boat. But, since the cabin moves with the passenger, one’s eyes register a relatively stable scene. Agitated by this perceptual incongruity, the brain responds with a cascade of stress-related hormones that can ultimately lead to nausea, vomiting, and vertigo.
Additionally, an affected person’s symptoms can be magnified by the strong odors of things like diesel fumes and fish. Seasickness usually occurs in the first 12 to 24 hours after “setting sail,” and dissipates once the body acclimates to the ship's motion. It’s rare for anyone to get or stay ill beyond the first couple of days at sea — unless the vessel encounters really rough waves.
If you do get seasick, take comfort in the fact that recovery is only a matter of time, and the survival rate is 100 percent! Sensible eating, good hydration, and some patience are all that are usually required to get past a bout of seasickness.
Here are a few tips to help ease the symptoms of seasickness: 1) Maintain your fluid intake. Seasickness and related medications cause dehydration and headaches. Drink water, low-acidity juices like apple and carrot, or clear soup, and avoid milk and coffee. 2) Keep moving. Most people find that being busy keeps their minds off their discomfort. 3) Stay on deck, even if it’s raining, because the fresh air is often enough to speed recovery. The closed-in quarters below deck magnify the vessel’s motion and worsen symptoms. 4) Carry a plastic bag. This simple approach allows for peace of mind by eliminating some of the panic of getting seasick. If you have to vomit "over the side,” though, check the direction of the wind and waves. Staying leeward (the side of the ship that’s sheltered from the wind) will ensure that an unpleasant experience doesn’t get even worse. 5) Consider an over-the-counter medication to prevent or minimize motion sickness. A dose is usually recommended about an hour prior to setting sail, and as needed at sea. These medications tend to be dehydrating, though, so drink plenty of water. And don’t be embarrassed for getting seasick. Many people do — including seasoned travelers, professional fishers, sailors, and marine scientists.
Mermaids and Sirens
Mermaids — those half-human, half-fish sirens of the sea — are legendary sea creatures chronicled in maritime cultures since time immemorial. The ancient Greek epic poet Homer wrote of them in The Odyssey. In the ancient Far East, mermaids were the wives of powerful sea-dragons, and served as trusted messengers between their spouses and the emperors on land. The aboriginal people of Australia call mermaids yawkyawks — a name that may refer to their mesmerizing songs. [Source: NOAA]
The belief in mermaids may have arisen at the very dawn of our species. Magical female figures first appear in cave paintings in the late Paleolithic (Stone Age) period some 30,000 years ago, when modern humans gained dominion over the land and, presumably, began to sail the seas. Half-human creatures, called chimeras, also abound in mythology — in addition to mermaids, there were wise centaurs, wild satyrs, and frightful minotaurs, to name but a few.
But are mermaids real? No evidence of aquatic humanoids has ever been found. Why, then, do they occupy the collective unconscious of nearly all seafaring peoples? That’s a question best left to historians, philosophers, and anthropologists.
The encounter of Odysseus and his men with the Sirens — humanlike female beings with alluring voices — at sea was one of the main events in Homer’s Odyssey. Odysseus had been warned about the Sirens by Circe so he knew what to do when he met up with them. He had himself tied to a mast so he could resist the sirens’ tempting song. His crew stuffed wax in their ears. If a man could resist the sirens's call, tradition stated, a siren had to die and she dutifully dived to her death into the sea.
Marine Wildlife Viewing Guidelines:
1) Learn before you go. Read about the wildlife, viewing sites, and local regulations to get the most from your wildlife viewing experience.
2) Keep your distance. Use binoculars, spotting scopes, and cameras with zoom lenses to get a closer look.
3) Hands off. Never touch, handle, or ride marine wildlife. Touching wildlife, or attempting to do so, can injure the animal, put you at risk, and may also be illegal for certain species.
4) Do not feed or attract wildlife. Feeding or attempting to attract wildlife with food, decoys, sound, or light disrupts normal feeding cycles, may cause sickness or death from unnatural or contaminated food items, and habituates animals to people. [Source: NOAA]
5) Never chase or harass wildlife. Never completely surround the animal, trap an animal between a vessel and shore, block its escape route, or come between mother and young.
6) Stay away from wildlife that appears abandoned or sick. Some marine animals, such as seals, leave the water or are exposed at low tide as part of their natural life cycle — there may be nothing wrong with them. If you think an animal is in trouble, contact local authorities for advice or report it to the NOAA Fisheries stranding network.
Reef Tips for Divers, Snorkelers and Swimmers:
1) Maintain natural buoyancy to avoid knocking or brushing against coral and marine life.
2) Coral is alive and easily damaged. Avoid touching, grabbing or standing on coral.
3) Please watch your fin wash. Sand can injure or smother small creatures and coral.
4) The underside of rocks are home to small creatures that can not live anywhere else. Please leave rocks, shells and coral in place for the reef dwellers who need them.
5) Killing, damaging, riding or chasing are examples of poor diver behavior.
6) Trash can kill marine life. Do not discard anything or let the wind blow it.
7) Feeding fish can make them pests, and some may even aggressive toward divers.
8) Use a permanent mooring buoy to secure your boat instead of dropping an anchor.
9) Do not collect live shells.
10) Please collect any trash you see on the beaches or in the water.
Products from the Sea
Products from the sea include fatty acids found in mother’s milk used in infant formulas produced by a marine micro-Algae; an enzyme used to decrease oil viscosity in underground wells from microbe found around undersea hydrothermal vents, Corals have the same porosity of human bone tissue and are being studied for use in artificial bone grafts.
A group of compounds with anti-inflammatory properties called pseudopterosins have been extracted from a Caribbean gorgonian (soft corral) and included in anti-wrinkle creams marketed by Estee Lauder.
The sea has also yielded some potent poisons.Nero’s mother Agrippina the Younger, eliminated rivals in her son’s path to the emperorship by poisoning their food with a toxin extracted from a shell-less mollusk known as a sea hare. Warriors on the Hawaiian island of Maui poisoned their spears with toxin from a toxic tidal-pool coral. Stricken warriors were killed even if they were only cut.
Some ethnic groups in eastern Siberia have traditionally made their clothes from fish skin. In the 1920s some women decorated their dresses with fish scales rather than sequins.” In a 1922 article in National Geographic, author Louis L Mowbray wrote: “An evening gown made wholly of bonefish scales... was indeed a thing of beauty. The scales were bored and laid on a fabric base like shingles on a roof. The resultant effect was like that of the natural body of the fish.”
The glue used by saltwater mussels to secure themselves to rock is made of proteins fortified with iron filtered from sea water. The glue is administered in dabs by the foot and is strong enough to allow the shell to cling to Teflon in crashing waves. Automakers use a compound based on blue mussel glue as an adhesive for paint. The glue is also being studied for use as a sutureless wound closure and dental fixative.
Peanut Butter, Coquina and Tabby
When it comes to eating, the ocean provides much more than just seafood. Many of the foods and products found in your local grocery store contain ingredients from the ocean. For example, peanut butter and toothpaste both contain carrageenan. Carrageenan is a generic term for compounds extracted from species of red algae. Boiling the algae extracts the carrageenan, which in turn is used to make peanut butter more spreadable. Carrageenan also gives toothpaste its consistency and is used in other cosmetics, pharmaceuticals, and industrial products. [Source: NOAA]
Coquina and tabby are “bullet-proof” building materials that come from of the sea. Near St. Augustine, Florida is an actual “castle” made of sand. — Castillo de San Marcos, the oldest (circa 1695) and largest masonry fort in the continental United States. The Castillo’s masonry, or stonework, is largely comprised of coquina (Spanish for “small shells”) — a natural concrete derived from the ocean. Coquina is a rare form of limestone composed of the shell fragments of ancient mollusks and other marine invertebrates, which, over time, are glued together by dissolved calcium carbonate in the shells. Coquina is also the name of a common tiny clam found everywhere on Florida beaches. Their shells, which come in countless colors, are reflected in the Castillo’s muted hues.
As a building material, coquina is lightweight, easy to find (it’s indigenous to the Florida coast), easy to use, and nearly indestructible. Not only is coquina bullet-proof, it is virtually cannon-ball- proof! Due to its plentiful microscopic air pockets, coquina is easily compressed. In days long past, cannon balls fired at the Castillo simply lodged in its walls. Which, one supposes, is why the old fort still stands after 300 years.
A related building material is tabby, often called coastal concrete, which is basically manmade coquina. Tabby is composed of the lime from burned oyster shells mixed with sand, water, ash, and other shells. As far back as the 1600s, Spanish and English settlers used tabby to build their homes and other structures, and to pave their roads, throughout the coastal Carolinas, Georgia, and Florida. Many tabby buildings still stand today, including Georgia’s Fort Pulaski near Savannah and the R.J. Reynolds mansion on Sapelo Island.
Drugs from the Sea
More promising drugs are being found in sea than in the rain forest. Dozens are in the clinical trials stage. Richard Sullivan, head of clinical programs at Cancer Research UK, told the Times of London: “The sea is proving to be a huge source of drugs and other molecular tools that can be used to help us understand, investigate and combat diseases like cancer. You often need a wide range of inhibitory agents to tackle diseases, and the marine environment is a huge repository for interesting substances.”
white tine sponge Algae, sponges sea urchins, soft corals and other non-fish marine organism are being tested for treatments for asthma, chronic pain and variety of cancers as well as for industrial chemicals — particularly adhesives. Hundreds of promising new biochemical substances from marine life have been extracted. Scientists sometimes collect samples by chiseling off materials from deep-sea oil platform and collecting water in syringes.
The U.S. National Cancer Institute has funded expeditions around the globe to collect marine samples. Samples are studied with automated chemical probes that seek out interesting strings of genetic material. Ones that hold promise are investigated further by scientists. Thousands of compounds have been screened. Of the ones that are made into drugs only about one or two make it to the preclinical test stage and of these only a handful become marketed drugs.
Scientists are searching the coral reefs and the sea, the same way they are searching in the rainforests, for miracle drugs. Some drugs have already been found. More seem on the way.The study of virus-killing chemicals in a Caribbean sponge in the 1950s led to the discovery of the AIDS-fighting drug AZT as well as Acyclovir, used to treat herpes infections. These have been called the first marine drugs. Sponges have also yielded cytarabine, a treatment for a kind of leukemia.
Some of the toxins found in soft corals are anti-inflammatory agents that have the potential of treating cancer, AIDS, asthma, heart disease and a host of other ailments. Scientist have found that toxins used by some nudibranchs to repel fish also work on land in bug sprays. The calcium secreting mechanisms of coral are being studied as means for repairing bones. Potential non-addictive painkillers have been discovered in sea whips and cone snails.
Sources of Drugs from the Sea
Actinomycetes bacteria from the Gulf of Mexico may yield an antibiotic. Compounds from Antarctic organisms are being studied for the treatment of cystic fibrous. Compounds from deep water sponges and spongy sea moss known as bryozoa are being studied for anti-cancer agents. Bryostatins derived from bryozoa are being used in clinical trials with sufferers of difficult-to-treat cancers such as ovarian, non-Hodgkins lymphoma and skin cancer.
“Nanoarchaeum equitans” is a unique organism collected from a sea floor vent north of Iceland. It is the simplest organism yet found, with less DNA than the simplest bacterium. The genome also is the smallest of any organism that has been sequenced. Scientists hope it will allow them to discard many genes found in other organisms.
Aerquorin is a green florescent protein extracted from the “Aequorea victoria” jellyfish found in shallow waters in the western Pacific. It is injected into cells and helps trace the irregular development of diseases such as cancer. It has proved invaluable helping scientist to figure out which cells and cell parts to target when combating cancer. The Japanese scientist that discovered won a Nobel Prize. Most glucosamine — an amino acid used to keep cartilage healthy and well lubricated — comes from shellfish. All this is nothing new. In the A.D. 1st century Pliny the Elder described using ground snails mixed with honey to treat “ulcerations of the head” and sea urchin ashes for baldness.
Eleutherobin, a chemical that comes from a mottled, yellow, pickled-shaped soft coral found off the coast of Australia, and a similar chemical from a sponge and a Mediterranean coral have been shown to stop the growth of malignant tumors. Dolastatin is a drug taken from an Indian ocean sea hare that shows promise in treating skin cancer and has made it as far as the clinical trial stage. A painkiller derived from a blue-green algae found near Curacao is being studied.
Ziconotide was the first drug of marine origin to obtain approval from the U.S. Food and Drug Administration (USFDA) in 2004 to treat pain. It is also known as Prialt, and it was originally extracted from the marine snail Conus magus. Results from animal studies suggested the role of ziconotide in blocking of N-type calcium channels on the primary nociceptive nerves of the spinal cord. [Source: Harshad Malve, Journal of Pharmacy and Bioallied Sciences, April-June 2016]
Types of Drugs That Come from the Sea
Harshad Malve, an India-based doctor, wrote in the Journal of Pharmacy and Bioallied Sciences: Marine drugs can be broadly classified based on their actions as follows: Antibacterial: Eicosapentaenoic acid, a polyunsaturated fatty acid, isolated from a diatom of marine origin Phaeodactylum tricornutum which has shown activity against an array of Gram-positive and Gram-negative bacteria, which also includes a multidrug-resistant variety of Staphylococcus aureus. [Source: Harshad Malve, Journal of Pharmacy and Bioallied Sciences, April-June 2016]
Anti-inflammatory: The anti-inflammatory function of extracts and other parts of a Mediterranean sponge species Spongia officinalis in the in vivo study on rat model of carrageenan-induced paw edema assay.
Neuroprotective: The extracts of South Indian green seaweed Ulva reticulata has shown neuroprotection by inhibiting acetyl-and butyryl-cholinesterases, efficacy comparable to agents currently approved for Alzheimer's disease treatment.
Antiparasitic: Extracts of Sarcotragus sp. known as Tunisian sponge prepared in dichloromethane has demonstrated in-vitro anti-leishmanial activity by demonstrating the associated morphological alterations in promastigotes of leishmania major.
Antiviral agents: Anti-herpes simplex virus-1 (HSV) activity found in high molecular weight exo-polysaccharides extracted from the Celtodoryx girardae (French marine sponge) and its associated symbiotic bacteria has been reported.
Antimicrobial: The cephalosporins are well-known antimicrobial agents with a marine source of origin. Cephalosporin C was firstly extracted and purified from a marine fungus, Cephalosporium acremonium.
Antimalarial activity: Isonitrile containing antimalarial molecules have been extracted from the Acanthella sp., a Japanese sponge. The isolated molecules belong to kalihinane diterpenoids class, which also contains antifungal, anthelmintic, and antifouling compounds.
Anti-Cancer Drugs from the Sea
On anti-cancer drugs from the sea, Dr. Harshad Malve wrote:Bryostatin, primarily obtained from the Bryozoan, Bugula neritina, although some forms have been extracted from sponges and tunicates. Sorbicillin-derived alkaloids sorbicillactone A and its 2', 3'-dihydro analog sorbicillactone-B has shown activity against leukemia cells free from any noteworthy cytotoxicity. Sorbicillactone-B has been derived from a salt-water culture of a bacterial strain Penicillium chrysogenum which has been isolated from a sponge Ircinia fasciculata, a Mediterranean sponge specimen. [Source: Harshad Malve, Journal of Pharmacy and Bioallied Sciences, April-June 2016]
Another promising anticancer drug used as an immunotherapeutic agent is keyhole limpet hemocyanin (KLH). KLH is a copper containing extracellular respiratory protein present in Megathura crenulata, a marine Gastropod species found in large numbers at the Pacific coast of California and Mexico. KLH is found in two isoforms KLH1 and KLH2. KLH is reported to possess remarkable immunostimulatory properties in experimental animals and human, used in experimental immunology and also clinically as an immunotherapeutic agent. KLH is specifically used in clinical setup for the treatment of bladder carcinoma, and its efficacy is perhaps due to a cross-reacting carbohydrate epitope. KLH may also have significant potential for the treatment of other types of cancers, particularly the adenocarciomas derived from the epithelium, by using it as a carrier for gangliosides of carcinoma and mucin-like epitopes.
KLH is intravesically administered to patients with bladder carcinoma. Its clinical success in carcinoma patients is attributed to the presence of the disaccharide epitope Gal (β1-3), Ga1NAc. This epitope of KLH is believed to be cross-reactive with an equivalent epitope on the urinary bladder tumor cell surface. The cumulative cellular and humoral immunological responses to KLH can result in a cytolytic reduction of tumor growth. In addition to tumor immunotherapy, KLH is also prescribed in the following conditions:
Image Sources: Wikimedia Commons; YouTube, NOAA
Text Sources: National Oceanic and Atmospheric Administration (NOAA) noaa.gov; “Introduction to Physical Oceanography” by Robert Stewart , Texas A&M University, 2008 uv.es/hegigui/Kasper ; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.
Last Updated March 2023