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ClamsplainingWhat are pearls?I often get asked what pearls are and why bivalves make them. Pearls are biogenic gemstones. This means they are valuable rocks made not by inorganic crystallization within the earth, like most gemstones, but instead are produced by life! Interestingly, they are living rocks, composed of true minerals. When I talk about minerals, I mean a solid substance with a known chemical composition and crystal structure. Pearls are specifically made mostly of a mineral called aragonite. Aragonite is a mineral made of atoms of calcium bound to an ion called carbonate. There are other minerals made from calcium carbonate, like calcite and vaterite. I’ll save those for another blog, and while those are present in small amounts in some pearls, the vast majority of the material is aragonite. The clam uses calcium carbonate to make pearls because it’s a conveniently available material: it’s also what they build their shells from!Aragonite has a very specific geometric crystal structure at the molecular level, but zooming out slightly, it can be found in a tremendous variety of microfabrics. Like the fabric of our clothes, the shell is essentially “woven” by the bivalve with a certain texture at the cellular level. There are hundreds of types of fabrics, ranging from structures looking kind of like brickwork, to plywood, to actual long fibers of carbonate. But the most valuable pearls are made of a form of aragonite called nacre, which is also called “mother of pearl” for this reason. The platy microstructure of nacre. See how the tablets are organized into interlocking columns! Source: Wikipedia Nacre is a very special biomineral for many reasons. To humans, it’s precious because of its beautiful, complex iridescence and luster, which has attracted our eyes for thousands of years. But most clams aren’t making the material for its luster- they value its microfabric. Nacre is made of billions of tiny flattened tablets of aragonite, arranged in tall interlocking stacks. Each aragonite tablet also has little bridges joining it to the neighboring tablet, meaning they don’t easily slide out of place. The plated structure also aids the shell in staying together. Even when fractured, the shell can stay together as plates slide to lock into another shape! Reviewing the various strengthening aspects of nacre, including the bridges that lock tablets together, the rough surfaces of the tablets that grip against each other, the organics that glue together tablets like mortar, and the tablets sliding into new locking orientations even if they break apart! From Zhao et al., 2018 Between the bricks of aragonite are a kind of mortar or scaffolding of protein, binding them all together. This protein scaffolding is extremely important to the overall material. Like the steel rebar in concrete, it strengthens the material, making it less brittle and therefore able to resist forces that might crush the clam’s shell, while still allowing for the material to be very thin. For us humans, those alternating layers of carbonate and protein act like thousands of layers of prisms, refracting the light into thousands of colors depending on the angle it is looked at, meaning that any light becomes a miniature rainbow when it passes through the structure of the nacre. A snuff box made from a nacreous bivalve shell, at the Vienna Natural History Museum This structure makes nacre a “premium” material for clams to build their shells from. It costs much more energy for a clam to make such an orderly microstructure and fill it with so much protein, up to 5% by weight, which is around 10-50 times how much organic material is found in other shell . Nacre is also more vulnerable to dissolving in the water surrounding the clam. For this reason, clams usually will only use nacre in the internal shell layer, isolated from the surrounding waters, using cheaper materials on the outside of the shell, or at least a protective sheath of protein on top (called periostracum). The nacre is present in mussels, oysters and other bivalves vulnerable to crushing pressures of waves as well as crushing predators like fish and birds. Nacre is like the bulletproof vest a clam uses to give itself a bit more powerful armor. Because pearls are made inside the shell, that’s why the most valuable pearls to us are made by oysters with a nacreous inner shell layer. The tropical pearl oysters (genus Pinctada) make some of the most valuable pearls, because it’s particularly rich in organic material and thus has a bright and complex lustre. Pearl oysters have extremely thin shells, which are strengthened by having a nacreous structure. They are Why do bivalves make pearls? Pearls are essentially part of the bivalve’s immune system. If a piece of sand or debris got under your skin, your body would encase the intrusive object with scar tissue. Bivalves can do better than that, because they use the material of the shell to wrap around the object. Anything can be an intrusive object- a piece of sand, an infection, or even a parasite. For example, pearlfish are parasitic fish specialized to live inside the shells of clams. If they die in the shell, the clam will dutifully set to work encasing the fish in nacre, like<a href="https://starwars.fandom.com/wiki/Hansicle" rel="nofollow noopener noreferrer" target="_blank"> Han Solo in carbonite</a>! A pearl oyster with a pearlfish wrapped in nacre against the inner shell. From the Natural History Museum London collection Most natural pearls are irregularly shaped, so cultured pearls often use round plastic beads as the nucleus for the oyster to grow nacre around. The farmer wedges the oyster’s shell open, deposits the bead and leaves it for a period of time to allow the bivalve to deposit nacre. At harvest time, the oyster can be shucked to remove the pearl. Some<a href="https://www.sciencedirect.com/science/article/abs/pii/S0044848608009332" rel="nofollow noopener noreferrer" target="_blank"> experimental approaches</a> even anaesthetize the oyster to remove the pearl, replace it with a new nucleus and repeat the process, potentially allowing for greater efficiency and humane harvesting, allowing the oyster stock to live for years!So next time you see a pearl, you can understand that the craftsmanship of these wondrous objects is the result of millions of years of evolution, combined with thousands of years of human ingenuity. Moving forward, researchers are attempting to learn to imitate the structure and methods that clams use to make pearls, which could lead to all sorts of improvements in materials science! Clams again prove their skill in engineering. They have a 500 million year head start against us, but we can always learn!<a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/aragonite/" target="_blank">#aragonite</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/biology/" target="_blank">#Biology</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/biominerals/" target="_blank">#biominerals</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/bivalves/" target="_blank">#bivalves</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/clams/" target="_blank">#clams</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/pearls/" target="_blank">#pearls</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/science/" target="_blank">#science</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/shells/" target="_blank">#shells</a>

Ms. Que BanhSitting & waiting to sign some documents & then can get out of this place, full of unmasked plague spreaders - at least for a few hours until I can bring my client her new air filtration unit.As I'm waiting, am reading up more on how to make reef balls out of broken seashells. Getting ahead on some research that will help me to help better with several projects along our coasts to restore Indigenous shellfish gardens & utilize the nature engineering powers of bivalves to restore some ocean ecosystems that were destroyed by acts of greed fueled colonialism.<a href="https://beige.party/tags/Decolonization" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Decolonization</a> <a href="https://beige.party/tags/rewilding" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#rewilding</a> <a href="https://beige.party/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a> <a href="https://beige.party/tags/MarineEcosystems" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#MarineEcosystems</a> <a href="https://beige.party/tags/VancouverIsland" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#VancouverIsland</a> <a href="https://beige.party/tags/CoastalBC" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#CoastalBC</a> <a href="https://beige.party/tags/Environmental" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Environmental</a> <a href="https://beige.party/tags/OceanRestoration" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#OceanRestoration</a>

michaellast year's feature on <a href="https://mastodon.social/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a> now in the open archives: <a href="https://proseandpassion.blogspot.com/2023/12/cockles-and-mussels.html" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://proseandpassion.blogspot.com/2023/12/cockles-and-mussels.html</a> <a href="https://mastodon.social/tags/science" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#science</a> <a href="https://mastodon.social/tags/ecology" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#ecology</a> <a href="https://mastodon.social/tags/MarineBiology" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#MarineBiology</a>

Lukas VFN 🇪🇺<a href="https://scholar.social/tags/Seagrasses" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Seagrasses</a> filter human <a href="https://scholar.social/tags/pathogens" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#pathogens</a> in marine waters <a href="https://phys.org/news/2024-08-seagrasses-filter-human-pathogens-marine.html" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://phys.org/news/2024-08-seagrasses-filter-human-pathogens-marine.html</a><a href="https://scholar.social/tags/Seagrass" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Seagrass</a> ecosystems as green urban infrastructure to mediate human pathogens in <a href="https://scholar.social/tags/seafood" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#seafood</a>: Phoebe Dawkins et al. <a href="https://www.nature.com/articles/s41893-024-01408-5" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://www.nature.com/articles/s41893-024-01408-5</a>Coastal urban seagrass ecosystems can significantly reduce human bacterial pathogens, including those with widespread <a href="https://scholar.social/tags/AntibioticResistance" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#AntibioticResistance</a>, in marine <a href="https://scholar.social/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a>—a vital food source for people around the world.

Jean-Pierre Gattuso 🇪🇺🇺🇦🍉Check out our new paper led by Fabrice Pernet on "Cracking the myth: Bivalve farming is not a CO2 sink”: <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/raq.12954" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://onlinelibrary.wiley.com/doi/epdf/10.1111/raq.12954</a><a href="https://fediscience.org/tags/CO2" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#CO2</a> <a href="https://fediscience.org/tags/ocean" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#ocean</a> <a href="https://fediscience.org/tags/aquaculture" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#aquaculture</a> <a href="https://fediscience.org/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a> <a href="https://social.numerique.gouv.fr/@cnrs" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@cnrs</a> <a href="https://social.numerique.gouv.fr/@CNRS_INSU" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@CNRS_INSU</a>

Cormacs CoastBivalve fossils in shale beds. County Clare, Ireland.Cormacscoast.com walking tours <a href="https://mastodon.sdf.org/tags/wildatlanticway" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#wildatlanticway</a> <a href="https://mastodon.sdf.org/tags/walkingtours" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#walkingtours</a> <a href="https://mastodon.sdf.org/tags/discoverireland" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#discoverireland</a> <a href="https://mastodon.sdf.org/tags/keepdiscovering" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#keepdiscovering</a> <a href="https://mastodon.sdf.org/tags/burrenandcliffsofmohergeopark" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#burrenandcliffsofmohergeopark</a> <a href="https://mastodon.sdf.org/tags/atlanticgeoparks" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#atlanticgeoparks</a> <a href="https://mastodon.sdf.org/tags/fossil" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#fossil</a> <a href="https://mastodon.sdf.org/tags/irishfossils" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#irishfossils</a> <a href="https://mastodon.sdf.org/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a> <a href="https://mastodon.sdf.org/tags/Ireland" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Ireland</a>

Ryan HodnettCockle (Cardiidae) <a href="https://commons.wikimedia.org/wiki/File:Cockle_(Cardiidae)_-_Oslo,_Norway_2020-12-23_(06).jpg" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://commons.wikimedia.org/wiki/File:Cockle_(Cardiidae)_-_Oslo,_Norway_2020-12-23_(06).jpg</a> <a href="https://commons.wikimedia.org/wiki/File:Cockle_(Cardiidae)_-_Oslo,_Norway_2020-12-23_(07).jpg" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://commons.wikimedia.org/wiki/File:Cockle_(Cardiidae)_-_Oslo,_Norway_2020-12-23_(07).jpg</a><a href="https://mastodon.world/tags/Cockle" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Cockle</a> <a href="https://mastodon.world/tags/MolluscMonday" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#MolluscMonday</a> <a href="https://mastodon.world/tags/Bivalve" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Bivalve</a> <a href="https://mastodon.world/tags/ArtWithOpenSource" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#ArtWithOpenSource</a> <a href="https://mastodon.world/tags/Darktable" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Darktable</a> <a href="https://mastodon.world/tags/CCBYSA" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#CCBYSA</a> <a href="https://mastodon.world/tags/Mollusc" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Mollusc</a> <a href="https://mastodon.world/tags/Molluscs" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Molluscs</a> <a href="https://mastodon.world/tags/Bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Bivalves</a> <a href="https://mastodon.world/tags/Shell" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Shell</a> <a href="https://mastodon.world/tags/Shells" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Shells</a> <a href="https://mastodon.world/tags/MarineLife" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#MarineLife</a> <a href="https://mastodon.world/tags/SeaLife" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#SeaLife</a> <a href="https://mastodon.world/tags/Nature" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Nature</a> <a href="https://mastodon.world/tags/NaturePhotography" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#NaturePhotography</a> <a href="https://mastodon.world/tags/Photography" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Photography</a>

Lukas VFN 🇪🇺Pacific <a href="https://scholar.social/tags/KelpForests" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#KelpForests</a> are way older than we thought <a href="https://www.futurity.org/pacific-kelp-forests-age-3167012/" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://www.futurity.org/pacific-kelp-forests-age-3167012/</a> Early <a href="https://scholar.social/tags/Oligocene" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#Oligocene</a> kelp holdfasts and stepwise <a href="https://scholar.social/tags/evolution" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#evolution</a> of the kelp ecosystem in the North Pacific <a href="https://www.pnas.org/doi/10.1073/pnas.2317054121" rel="nofollow noopener noreferrer" translate="no" target="_blank">https://www.pnas.org/doi/10.1073/pnas.2317054121</a>"<a href="https://scholar.social/tags/kelp" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#kelp</a> flourished off the US Northwest Coast more than 32 million years ago, long before the appearance of modern groups of marine <a href="https://scholar.social/tags/mammals" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#mammals</a>, <a href="https://scholar.social/tags/SeaUrchins" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#SeaUrchins</a>, <a href="https://scholar.social/tags/birds" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#birds</a>, and <a href="https://scholar.social/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a> that today call the forests home."

Alice DennisDon't forget to submit your <a href="https://genomic.social/tags/mollusc" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#mollusc</a> <a href="https://genomic.social/tags/genomics" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#genomics</a> abstract for our upcoming meeting! A few spots still remain.<a href="https://genomic.social/tags/EMBOMolluscGenomics" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#EMBOMolluscGenomics</a> <a href="https://genomic.social/tags/UniversityofNamur" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#UniversityofNamur</a> <a href="https://genomic.social/tags/evolution" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#evolution</a> <a href="https://genomic.social/tags/ecology" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#ecology</a> <a href="https://genomic.social/tags/neuroscience" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#neuroscience</a> <a href="https://genomic.social/tags/physiology" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#physiology</a> <a href="https://genomic.social/tags/snails" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#snails</a> <a href="https://genomic.social/tags/bivalves" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#bivalves</a> <a href="https://genomic.social/tags/chitin" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#chitin</a> <a href="https://genomic.social/tags/octopus" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#octopus</a> and all the rest welcome!

Clamsplaining The streamlined shells of Gaimardia trapesina. Source: <a href="http://www.mollusca.co.nz/specieslist.php?sf=304#prettyPhoto[img_group]/2/" rel="nofollow noopener noreferrer" target="_blank">New Zealand Mollusca</a>Bivalves are not known as champion migrators. While scallops can swim and many types of bivalves can burrow, most bivalves are primarily sessile (non-moving on the ocean bottom). So for many bivalves, the primary method they use to colonize new territories is to release planktotrophic (“plankton-eating”) larvae, which can be carried to new places by currents and feed on other plankton surrounding them. Many bivalves have broad distributions because of their ability to hitchhike on ocean currents when they are microscopic. They don’t even pack a lunch, instead eating whatever other plankton is around them. But once they settle to grow, they are typically fixed in place.Not all bivalves have a planktotrophic larval stage, though. Larvae of <a href="http://invert-embryo.blogspot.com/2013/05/planktotrophy-versus-lecithotrophy.html" rel="nofollow noopener noreferrer" target="_blank">lecithotrophic</a> bivalve species (“yolk-eaters”) have yolk-filled eggs which provide them with a package of nutrition to help them along to adulthood. Others are brooders, meaning that rather than releasing eggs and sperm into the water column to fertilize externally, they instead internally develop the embryos of their young to release to the local area when they are more fully developed. This strategy has some benefits. Brooders invest more energy into the success of their offspring and therefore may exhibit a higher survival rate than other bivalves that release their young as plankton to be carried by the sea-winds. This is analogous to the benefits that <a href="https://en.wikipedia.org/wiki/R/K_selection_theory" rel="nofollow noopener noreferrer" target="_blank">K-strategist</a> vertebrate animals like elephants have compared to r-strategist mice: each baby is more work, and more risky, but is more likely to survive to carry your genes to the next generation.Brooding is particularly useful at high latitudes, where the supply of phytoplankton that is the staple food of most planktrophic bivalve larvae is seasonal and may limit their ability to survive in large numbers. But most of these brooding bivalves stay comparatively local compared to their planktonic brethren. Their gene flow is lower on average as a result, with greater diversity in genetic makeup between populations of different regions. And generally, their species ranges are more constricted as a result of their limited ability to distribute themselves.A bunch of G. trapesina attached to kelp. Notice the hitchhiking clams have in turn had hitchhiking barnacles attach to them. Freeloaders on freeloaders! Source: <a href="http://eleonorapuccinelli-naturalview.com/research/" rel="nofollow noopener noreferrer" target="_blank">Eleonora Puccinelli</a>But some brooding bivalves have developed a tool to have it all: they nurture their young and colonize new territories by sailing the seas using kelp rafts. The clam Gaimardia trapesina has evolved to attach itself to giant kelp using long, stringy, elastic byssal threads and a sticky foot which helps it hold on for dear life. The kelp floats with the help of gas-filled <a href="https://en.wikipedia.org/wiki/Pneumatocyst" rel="nofollow noopener noreferrer" target="_blank">pneumatocysts</a>, and grows in the surge zone where it often is ripped apart or dislodged by the waves to be carried away by the tides and currents. This means that if the clam can persist through that wave-tossed interval to make it into the current, it can be carried far away. Though they are brooders, they are distributed across a broad circumpolar swathe of the Southern Ocean through the help of their their rafting ability. They nurture their embryos on specialized <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1744-7410.2009.00171.x" rel="nofollow noopener noreferrer" target="_blank">filaments </a>in their bodies and release them to coat the surfaces of their small floating kelp worlds. The Southern Ocean is continuously swirling around the pole due to the dominance of the Antarctic Circumpolar Current, which serves as a constant conveyor belt transporting G. trapesina across the southern seas. So while G. trapesina live packed in on small rafts, they can travel to faraway coastlines using this skill.The broad circumpolar distribution of G. trapesina. Source: <a href="https://www.sealifebase.ca/summary/Gaimardia-trapesina.html" rel="nofollow noopener noreferrer" target="_blank">Sealifebase</a>The biology of G. trapesina was described in greater detail in<a href="https://link.springer.com/article/10.1007/s00227-018-3430-z" rel="nofollow noopener noreferrer" target="_blank"> a recent paper </a>from a team of South African researchers led by Dr. Eleonora Puccinelli, who found that the clams have evolved to not bite the hands (kelp blades?) that feed them. Tests of the isotopic composition of the clams’ tissue shows that most of their diet is made up of detritus (loose suspended particles of organic matter) rather than kelp. If the clams ate the kelp, they would be destroying their rafts, but they are gifted with a continuous supply of new food floating by as they sail from coast to coast across the Antarctic and South American shores. But they can’t be picky when they’re floating in the open sea, and instead eat whatever decaying matter they encounter.Falkland Islands stamp featuring G. trapesina. <a href="https://colnect.com/en/stamps/stamp/177689-Shell_Gaimardia_trapesina-South_Georgia_and_South_Sandwich-Falkland_Islands_Dependencies" rel="nofollow noopener noreferrer" target="_blank">Source</a>.The clams are small, around 1 cm in size, to reduce drag and allow for greater populations to share the same limited space of kelp. Their long, thin byssal threads regrow quickly if they are torn, which is a useful skill when their home is constantly being torn by waves and scavengers. Unlike other bivalves, their shells are thin and fragile and they do not really “clam up” their shells when handled. They prioritize most of their energy into reproduction and staying stuck to their rafts, and surrender to the predators that may eat them. There are many species that rely on G. trapesina as a food source at sea, particularly traveling seabirds, which descend to pick them off of kelp floating far from land. In that way, these sailing clams serve as an important piece of the food chain in the southernmost seas of our planet, providing an energy source for birds during their migrations to and from the shores of the Southern continents. <a href="https://dantheclamman.blog/2018/10/19/the-clams-that-sail-the-seas-on-rafts-of-kelp/" class="" rel="nofollow noopener noreferrer" target="_blank">https://dantheclamman.blog/2018/10/19/the-clams-that-sail-the-seas-on-rafts-of-kelp/</a><a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/antarctic/" target="_blank">#antarctic</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/biology/" target="_blank">#Biology</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/bivalves/" target="_blank">#bivalves</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/clams/" target="_blank">#clams</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/ecology/" target="_blank">#ecology</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/embryology/" target="_blank">#embryology</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/gaimardia/" target="_blank">#gaimardia</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/invertebrates/" target="_blank">#invertebrates</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/kelp/" target="_blank">#kelp</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/marine-biology/" target="_blank">#marineBiology</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/marine-life/" target="_blank">#marineLife</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/oceans/" target="_blank">#oceans</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/physiology/" target="_blank">#physiology</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/research/" target="_blank">#research</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/science/" target="_blank">#science</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/shells/" target="_blank">#shells</a> <a rel="nofollow noopener noreferrer" class="hashtag u-tag u-category" href="https://dantheclamman.blog/tag/southern-ocean/" target="_blank">#southernOcean</a>

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