89 votes
Accepted

Why would an underwater creature remain lodged to its prey?

To be annoyingly clingy Your super lobsters seems to have the ability to hunt anything. The barbs makes it easier for a team of them to hunt prey much larger than themselves. The main purpose of ...
SE - stop firing the good guys's user avatar
60 votes

An underwater creature that could take down a boat

Give that Columbus' craft were built using Carvel construction (butt jointed wood caulked with tarred hemp that is hammered into the joints and then a coat of tar over everything beneath the waterline)...
Michael Broughton's user avatar
56 votes
Accepted

A fast aquatic predator with multiple eyes and pupils. Would these eyes be possible?

This is the four-eyed fish: It has only two eyes, but it has two pupils and two retinas in each eye. It evolved to hunt by the water surface, catching prey from both above and below. Where there is ...
The Square-Cube Law's user avatar
48 votes

Why would an underwater creature remain lodged to its prey?

Because you are a sprinter only (in contrast to your prey) Some animals such as cheetahs are not capable of hunting a prey such as a gazelle for more than a few hundred metres. The gazelle is capable ...
thomastiger's user avatar
47 votes
Accepted

Could a jellyfish be bio-engineered to convert salt water into fresh water?

No. Jellyfish are osmoconformers Osmoconformers are marine organisms that maintain an internal environment that is osmotic to their external environment.[1] This means that the osmotic ...
Willk's user avatar
  • 304k
46 votes
Accepted

What if the ocean's salt level decreased by 50%?

Phase 1: The Extinction Most life in the sea would die out almost immediately. Saltwater fish, invertebrates, and most importantly plants and microbes are finely-tuned for a particular level of ...
IndigoFenix's user avatar
45 votes
Accepted

Living biological boats? (Jasconius)

That's where its food source is. Most algae is found near the surface of the ocean, so if this creature has a semi long neck, it can swim gently along moving its head back and forth, up and down ...
Dan Clarke's user avatar
  • 7,211
43 votes
Accepted

Would the existence of Megalodon during the medieval ages threaten Sea Travel and how to defend against them?

No Megaladon is not fundamentally a more fearsome or ferocious beast than a sperm whale, which is also carnivorous, of similar size, probably smarter, and has as documented capability to sink 240 ton ...
kingledion's user avatar
  • 85.1k
40 votes

How would a ship defend against a sea creature, and possibly win?

Rolling attack - Have a heavy keel I just wrote a big post about naval architecture principles, much of which applies here as well. To minimize the chance your ship rolls, attach a heavy keep to the ...
kingledion's user avatar
  • 85.1k
39 votes

Would oceans filled with long-lived, omnivore, intelligent Krakens make sea travel impossible?

Octopi play. source The ocean can be terrifying. More terrifying is being played with by an intelligent predator. It grabs a person then leaves. It hits the boat and then leaves. It throws a huge ...
Willk's user avatar
  • 304k
35 votes

Why would a species that had never been exposed to light react to light?

Because it can still feel temperature differences. Light is energy. Depositing energy on the skin (or deeper in the body, if the skin is transparent, as it often is for deep sea creatures that live in ...
Logan R. Kearsley's user avatar
34 votes

Would evolution select for mermaids without breasts?

A walrus A hippo Both of them can swim much faster than a human being, despite the clumsy looking proportions and giant weights. Next are the winners of different length swimming contests in Dubai ...
Youstay Igo's user avatar
  • 20.6k
30 votes

Living biological boats? (Jasconius)

Needs sunlight It could have a usage for sunlight. Maybe a system similar to how plants use sunlight in photosynthesis. Heck, it could be exactly that. Make it have cells with photosynthetic ...
Rick M.'s user avatar
  • 873
30 votes
Accepted

Would merfolk gain any real advantage from mounts (and beasts of burden)?

Yes, they would. I can affirm this because mounts follow the general yet extremely potent principle of specialization : A specialized entity -person, machine or animal- will always perform better than ...
Tortliena's user avatar
  • 7,468
29 votes

Why would an underwater creature remain lodged to its prey?

They feed through their horn There are animals that already do this, the most famous of which are leeches, ticks and lampreys. They attack their prey, latch on, feed, then let go once they're either ...
Nzall's user avatar
  • 8,439
26 votes
Accepted

How long could a Kraken's carcass survive if preserved in salt?

I'm going to assume that when you say "Kraken" you mean "giant octopus monster" meaning something biochemically identical to a modern octopus but huge. I'm also assuming that the water stays gone and ...
Ash's user avatar
  • 44.7k
26 votes

Hammering under water?

That would be not a hammer, but an axe. Stone age hammers and axes did not differ much, and in most cases were both - depending on the side you used (this is still the case for "civil" axes). An axe ...
ksbes's user avatar
  • 9,915
25 votes

An underwater creature that could take down a boat

This is not as straight-forward as it sounds. Some problems as I see them: 1. Oceanic Exploration Not a New Thing At the time that Columbus "discovered" the New World, the Vikings had already ...
AndreiROM's user avatar
  • 34.7k
22 votes

An underwater creature that could take down a boat

The most realistic way—historically correct, even—seems to be a case of the overly hungry naval shipworm (Teredo navalis var. esuriens). Columbus had a large problem with them, the ...
deamentiaemundi's user avatar
22 votes

Would oceans filled with long-lived, omnivore, intelligent Krakens make sea travel impossible?

I am not sure that those kraken would consider human ships interesting prey. After all most of the ship is inedible (wood) and hunting those little, pesky critters hugging to the "huge log" ...
Archelaos's user avatar
  • 2,281
21 votes
Accepted

An underwater creature that could take down a boat

Mega-AquaBoa-Constrictor The problem I have with animals biting the ship is that one bite would likely deter them. It seems like a lot of sea animals like sharks usually take one bite of something ...
Mikey's user avatar
  • 17.4k
20 votes
Accepted

What underwater creature would be well-suited as a pack animal?

You're going to want to obtain some whales. Not only are they the largest mammals alive, they also have the largest muscles. Whales travel in pods, the equivalent of a "pack" of wolves. They're ...
Aify's user avatar
  • 19k
20 votes

Why would modern humans not use scuba gear for missions underwater? (But freedive instead)

Stealth Man-made materials like metals, plastics, and ceramics have very distinct qualities that allows Sirens to immediately identify submarines and scuba gear from miles away. It's so distinct if ...
Nosajimiki's user avatar
  • 87.8k
19 votes

Sonar Jamming Squids

A cloud of smaller host creatures scatters the sonar. The squid is followed by a cloud of small creatures that scavenge the scraps of the squid's food. In return they serve to scatter the sonar waves ...
Daron's user avatar
  • 65.6k
18 votes

Would evolution select for mermaids without breasts?

Evolution would select for human style breasts ...given a few things are true. First, humans have effectively removed predatory pressure as a cause for human evolution, and with sapience I would say ...
James's user avatar
  • 32.8k
18 votes

What if the ocean's salt level decreased by 50%?

Life would not be able to evolve in this short amount of time. Organisms able to survive the lower salt concentrations (of which there would be some in the ocean) would survive, organisms not able to ...
Jarred Allen's user avatar
  • 4,768
18 votes

How would a ship defend against a sea creature, and possibly win?

If your kraken is basically like a giant squid, we can take a two-pronged approach to defend against all of your attack methods. First we want to prevent the kraken from grabbing hold of your ship to ...
ColonelPanic's user avatar
  • 3,022
18 votes
Accepted

Could a mature (and giant) lobster remain in sea water indefinitely without decaying?

What would she look like after a few hundred years of submersion? Like a really big lobster. Regular lobsters live in the sea, and can live to over 100 years old and still look just like lobsters. ...
Starfish Prime's user avatar
16 votes

Living biological boats? (Jasconius)

Buoyancy is a big deal for sea creatures. Pretty much everything living on or in water have a density that makes them naturally comfortable (i.e. energy efficient) only at certain depths, and changing ...
goldPseudo's user avatar
16 votes

Under what circumstances would a nuclear war render Earth's oceans uninhabitable?

Not possible. You land dwellers need the ocean to survive. Don't forget that the oceans are part of the water cycle. If they are so messed up from radiation that no life can thrive in them, then the ...
The Square-Cube Law's user avatar

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