Dr. Dan KillamJun 9
Giant clams produce ~8 kg/cm2 of closure pressure (114 psi), less than a human bite. So you'd feel a big pinch if one closed on you, but not dangerous! They generally don't want you in their shells with them, so they'll reopen if you keep still, and large clams often can't close completely. However, since their shells are so heavy, their adductor muscles must be very resilient, sustaining >500 kg of tension for mature individuals! #clamFacts
Show threadsoaprootJun 9

@bug_gwen The best example I could find of a land clam is "The saddle oyster, Enigmonia aenigmatica, is a marine species that could be considered amphibious. It lives above the high tide mark in the tropical Indo-Pacific on the underside of mangrove leaves, on mangrove branches, and on sea walls in the splash zone." (from Wikipedia)

So I think the shrimps win this round.

#clamFacts

Dr. Dan KillamJun 8
Contrary to their name, American oystercatchers don't *just* eat oysters. In one study, around 2/3 of their diet was actually sand crabs. But they do eat a lot of bivalves, using their chisel-like, fast-growing bills to smash or pry open oysters, mussels and other intertidal bivalves! Murder! 🫣 #clamFacts
Dr. Dan KillamMay 30
Oysters are often farmed in floating cages or bags. This way they are protected from many predators, and floating near the surface they are always among the the tasty phytoplankton that are their preferred food, rather than having to wait for the plankton to sink to the bottom! #clamFacts
Show threadDr. Dan KillamMay 30
@soaproot yes giant clams are interestingly "easiest" (still not a beginner pet) as they can get most of their nutrition from light. But most filter-feeding clam species will need supplemental cultured plankton to be added, which most home aquarists aren't prepared to do! #clamFacts
neville parkMay 26

at the risk of competing with #ClamFacts, check out the latest Skype A Scientist merch: a T-shirt full of SHRIMP (& friends) FACTS  

edit: fuck me forgot theurl https://squidfacts.bigcartel.com/product/shrimp-city-t-shirt-pre-order

#crustaceans #shrimp #Crustacea #phylogeny

Show threadDr. Dan KillamMay 25
@kboyd I couldn't find a study trying that, but it is a major focus of research from the perspective of light pollution and reducing artificial light at night. But in a similar approach, they have found in multiple experiments that when they play audio of oyster reefs they can induce larvae to settle! #clamFacts https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0079337
Oyster Larvae Settle in Response to Habitat-Associated Underwater Sounds

Following a planktonic dispersal period of days to months, the larvae of benthic marine organisms must locate suitable seafloor habitat in which to settle and metamorphose. For animals that are sessile or sedentary as adults, settlement onto substrates that are adequate for survival and reproduction is particularly critical, yet represents a challenge since patchily distributed settlement sites may be difficult to find along a coast or within an estuary. Recent studies have demonstrated that the underwater soundscape, the distinct sounds that emanate from habitats and contain information about their biological and physical characteristics, may serve as broad-scale environmental cue for marine larvae to find satisfactory settlement sites. Here, we contrast the acoustic characteristics of oyster reef and off-reef soft bottoms, and investigate the effect of habitat-associated estuarine sound on the settlement patterns of an economically and ecologically important reef-building bivalve, the Eastern oyster (Crassostrea virginica). Subtidal oyster reefs in coastal North Carolina, USA show distinct acoustic signatures compared to adjacent off-reef soft bottom habitats, characterized by consistently higher levels of sound in the 1.5–20 kHz range. Manipulative laboratory playback experiments found increased settlement in larval oyster cultures exposed to oyster reef sound compared to unstructured soft bottom sound or no sound treatments. In field experiments, ambient reef sound produced higher levels of oyster settlement in larval cultures than did off-reef sound treatments. The results suggest that oyster larvae have the ability to respond to sounds indicative of optimal settlement sites, and this is the first evidence that habitat-related differences in estuarine sounds influence the settlement of a mollusk. Habitat-specific sound characteristics may represent an important settlement and habitat selection cue for estuarine invertebrates and could play a role in driving settlement and recruitment patterns in marine communities.

Dr. Dan KillamMay 25
Larval oysters have an eye which can detect wavelength and intensity of light. They use the ratio of red and blue light to determine the correct depth at which to settle and attach to the bottom, working from the principle that red light doesn't penetrate as far into the water as blue light! They are phototaxic, attracted to depths where red light is present, and swim up and away from places where only blue light is present #clamFacts
Dr. Dan KillamMay 20
In the Philippines, shipworms (bivalves that eat wood) are called tamilok and are often eaten raw, marinated in citrus in a ceviche-like dish called kinilaw. They also can be deep fried. The taste has been compared to oysters! Since they can be grown with such limited resources, basically just requiring wood, researchers are trying to develop it as a sustainable seafood! I would consider trying it fried but I think I'll leave kinilaw for the more developed palates 😅 #clamFacts
Dr. Dan KillamMay 19
If a bivalve shell has a big honkin snoot off to one side, it is called 'rostrate'. Such structures are often a sign of a big siphon. In the most extreme cases, such as for Cuspidaria, it can a sign of carnivory, with them using a long vacuum hose-like siphon to suck up prey! All the better to eat copepods with! #clamFacts