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The study of organisms that dwell in the ocean or brackish waters.

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How long could a shark breathe pepsi?

Sharks breathe seawater. Seawater isn't 100% pure water, but mostly water. Pepsi (other colas are available) isn't 100% pure water, but mostly water. How long would a shark be able to breathe if ...
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23 views

What species of fish is this?

I have a horrible memory, and I forgot what species he was soon after I bought him. I've had him for almost six months, and he's just so neat looking that I want to know more about him.
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What kind of sieve does one use to extract meiofauna?

Suppose I have a core of sediment, and I want to extract the meiofauna from it, in order to study these organisms. According to the sources I could find, this involves using a very fine (e.g. 45 μm) ...
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3answers
292 views

Were there any marine/aquatic dinosaurs?

Most dinosaurs were terrestrial, but there were a couple of groups of arboreal and flying dinosaurs (microraptors, birds etc). I have read that the theory that Brachiosaurids were aquatic has been ...
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seafood muscles - how do they work?

Today, first time in my life I ate seafood. It was a squid and a calamar. Note that I am biology layman, so please be merciful :( While dissecting my food I noticed that the tissues of those ...
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0answers
19 views

How do plastic containers and other thrash end up in the ocean [closed]

There are many photos of the ocean, which in some parts is littered with all sorts of waste, often plastic bags, containers etc. But I just wonder - how do such large amounts land in the ocean/sea? ...
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1answer
111 views

Did the construction of the Panama Canal lead to a huge change in the local marine ecology?

Before the Panama Canal opened in 1914, its two ends were only 77 km apart over land, but the closest sea route was 32,000 km long (around the entirety of South America) and passed through much colder ...
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0answers
37 views

Which scallops change their sex from male to female?

Tonight it occurred to me to look up what scallops are like when they are alive (beyond their culinary role) and it blew my mind. This post regards one detail about which I was unable to find specific ...
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3answers
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Inexperienced divers damage coral, but parrot fish eating coral doesn't do damage?

I've been learning about life on coral reefs. Recently I've become aware of the damage to coral reefs caused by tourism and inexperienced divers: 1) Corals have a thin membrane which keeps them ...
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1answer
37 views

Resources to learn about marine life

I recently saw the documentary series Blue Planet 2 and was mesmerised by it. Can someone recommend me some resources to learn about marine life? I am particularly looking for those that detail the ...
4
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1answer
59 views

Octopus behaviour

When visiting a museum in Malmo my friends and I came across this little guy. While we observed him wandering around his tank he suddenly opened a channel on the side of his head and shot some red ...
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0answers
55 views

What is this whitish jelly incrustation on a plastic tube?

I found this plastic tube hanging in the seawater from a pier in the haven of Taranto, Ionian sea, southern Italy. I'm wondering what is the whitish jelly in the lowest part of the photo next to the ...
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1answer
76 views

How did shellfish and coral survive acidic oceans in earlier eras?

Throughout most of Earth's history, the planet has had more CO2 in its atmosphere, correct? Therefore th pH of the oceans was even lower, right? So how did CaCO3-using animals create their shells ...
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87 views

identify an unknown crustacean found in Vietnam

Could someone please let me know the name of this crustacean? This species was found in Vietnam. Much appreciated
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2answers
69 views

I found this on the beach at Breamlea in Vic Australia and wondered if you could tell me what it is please

It is about 6.5 x 5 centimetres and semi transparent. It has quite a tough skin and is hollow inside. Like a tight clear tooth shaped balloon. I have put a coin next to it for you to see the size.
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0answers
65 views

is this a soft coral on sand?

Was diving a few days ago at Jervis Bay (Australian East Coast - temperate). Water temp 20 degrees C, depth 5m. Spotted this creature in the sand. About 150mm high. It isn't sea-pen (Cnidarian) as it ...
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1answer
430 views

Why are there no fresh water osmoconformers?

I'm just having trouble understanding this. I know that often marine fish are osmoconformers, and freshwater (like bony fish) are often osmoregulators, but why?
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0answers
29 views

Why does the colour of the Earth‘s oceans vary?

Why does the colour of the Earth‘s oceans vary? Coast lines around the world appear to have different shades of blue. The further one travels from the equator north or south the deep blue the ocean ...
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1answer
385 views

Is the Opah a warm blooded fish?

In 2015 many sources, including USA TODAY, Discover Magazine, and National Geographic, ran stories about the Opah fish (Lampris guttatus) being warm blooded. Image Source: http://discovermagazine.com/...
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1answer
65 views

why can't humans live underwater like seals or whales? [closed]

I was wondering, why can't humans live under water like whales or seals? If whales can live underwater, and they're mammals, why can't we?
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1answer
76 views

Are freshwater jellyfishes really jellyfishes?

Articles from the aquaticcommunity.com and the Nature Conservancy suggest that freshwater jellyfish, Craspedacusta sowerbyi, are more closely related to the Genus Hydra. From the Nature Conservancy ...
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0answers
122 views

Please identify this creature found on the beach

Found on beach in Atlantic Canada in November. "Sack" is approx. 2" (approx. 5cm) in length.
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1answer
217 views

What is this strange horned, slug-like coral reef dwelling creature?

On the first episode of BBC's Blue Planet II they visited a coral reef and showed some odd reef-dwelling creatures as part of their establishing shots, but they did not identify the creatures. What ...
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1answer
88 views

What is this strange mantis-like coral reef dwelling creature?

On the first episode of BBC's Blue Planet II they visited a coral reef and showed some odd reef-dwelling creatures as part of their establishing shots, but did not name the creatures. In particular ...
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1answer
122 views

Identify this tuber like object found on beach

Can anyone identify this tuber-like object I found on a beach in South Wales, UK? It's about 25 cm long and looks like a deflated football. Pretty spongy, saturated with water. I was hoping it was ...
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0answers
32 views

Can a shark stall?

Today in marine biology I learned that, like airplanes, sharks use their pectoral fins to generate lift. The question that neither me or my Professor know is if a shark can or cannot stall. A ...
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0answers
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Has a walrus ever been filmed catching a seal under water?

Walruses have been long thought to be grazing feeders, scooping up clams from the sea floor. However, when walruses bodies have been examined by scientists, frequently the remains of seals are found ...
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0answers
70 views

How do marine mammals stay hydrated?

This is a question that has always bothered me. A quick internet search yields "metabolic processes" as the reason for how marine mammals obtain water, but what are those processes and why don't land ...
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0answers
19 views

Does overfishing in one ocean hurt fishstock in another?

If there's overfishing in the Atlantic or North Sea - will this affect fish stocks in the Indian ocean? Are there papers on this? The question I'm trying to answer is whether overfishing by developed ...
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4answers
486 views

What sea animal is this?

I am in a remote village and a young boy (second pic holding tail) says this thing is his friend. This creature is safe, we held it for pictures and released it after. None of us know what this is and ...
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1answer
113 views

Why do sea mammals die on land, and drown on sea?

It's quite confusing to me, why do sea mammals die on land, but also die from drowning if they couldn't reach the sea surface to breath? Excuse my ignorance but I am really confused!
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1answer
771 views

Rock cod vs grouper

What is the difference between a rock cod and a grouper? The only difference I notice is that grouper seems to be bigger in size. But other than that, they are very similar.
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1answer
158 views

What sounds deter sharks?

Have any studies been done to find sounds that alienate sharks?
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0answers
104 views

Function of the spermaceti organ

What is the use of the spermaceti organ of the sperm whale? One possible theory considered is that it was used for floating and going underwater by heating/cooling the oil. However, it is a lot ...
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1answer
1k views

What percentage of fish are herbivorous vs. carnivorous?

It appears that the majority of fish we eat are carnivorous, such as salmon and tuna. This got me wondering how common herbivores and carnivores are among fish species. I couldn't find an answer to ...
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1answer
147 views

Help identify these (two) fishes - Netherlands

Yesterday my kids caught these two fish. I tried to figure out what kind of fish (species and name, to tell my kids a bit more about them) they are but I was not successful. Today we made a trip to a ...
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0answers
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Is there a cellular physiological response to desiccation in animals?

There has been much research on the molecular effects of high levels of temperature for animals, specifically regarding heat shock proteins, protein denaturing and energy investment into stress ...
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2answers
127 views

Are lanternfish real?

Is there a real lantern fish existing in the world? If yes, kindly share a picture if one exists. I searched online for images, but most of them seem to be fake. The pictures I have seen on the ...
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1answer
67 views

Where can I find comprehensive data on animal distribution?

I'm looking for vertical distribution or tidal height of several intertidal species, specifically from the Pacific Northwest. I considered looking for published research for each species however, my ...
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2answers
175 views

ID a marine creature found on a beach on the US east Coast

While walking on a marshy beach, I found this creature. It has no eyes, no feet, no fin, no gills. The only thing I know is that the skin lightly contracts. I found at least three of these. It is ...
8
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1answer
306 views

ID a shell from Puerto Rico

I recently found this in Rincon Puerto Rico on the beach. I assumed it was a baby sea turtle shell or some kind of turtle. Someone that frequents Puerto Rico said it was not. Does anybody know what ...
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1answer
125 views

Organic battery?

Similar to the Matrix movie where humans were used as a source of electricity but different by using electric eels. Farmed like tuna what would be the electricity exchange to the food they eat?
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1answer
156 views

Do pyrosomes reproduce by ways other than cloning?

I know that Pyrosomes are large colonies of floating tube-like animals that live in the sea, particularly in the tropics. They are just like any type of free floaters I know that pyrosomes can ...
4
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1answer
203 views

Why do Great White Sharks not survive in captivity?

Keeping any large marine predator in captivity is a challenge. While it has been done with both mammals and some sharks, it has never been successful with Great White Sharks. The longest a Great White ...
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0answers
187 views

Calcium carbonate minerals in marine organisms shells

Calcium carbonate minerals exist in seawater in two main phases: calcite and aragonite. While calcite is the most stable phase, it is aragonite that precipitates first in seawater because of the high ...
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2answers
269 views

How does eutrophication yield lower levels of dissolved oxygen? [closed]

Where do the oxygen go? Is it consumed by a particular species? Is just not enough being made? Please explain.
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1answer
669 views

Identification of colorful jelly-like marine creature

I'm on my trip to Gulangyu Island, Xiamen, Fujian Province, China. Today(4th February 2017), at 12:13 A.M., I saw a beach filled with huge rocks on which various dry shells reside. Among the shells, I ...
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0answers
66 views

Why do most fish move fins orthogonally with their axis of symmetry?

So recently I read the question why are most fishes vertical (in the sense of distribution of their body mass) and it got me thinking what is the reason behind the direction they move their fins. My ...
3
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1answer
76 views

What forms the base of the coral reef ecosystem?

Corals are small animals that form a symbiotic relationship with algae. The algae produce sugars for the corals and are in turn provided with needed nutrients and protection from predators. That's ...
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1answer
118 views

Why are there relatively more predators on the land than in the oceans? [closed]

Our biology teacher told us that among worse conditions one of the reason that intelligent life had actually evolved on land is that there is a more important selective pressure due to the bigger ...