44

Your worms are ambush predators. They very rarely move. https://www.bbcearth.com/blog/?article=snapping-death-worms-can-hide-undetected-for-years These giant polychaete marine worms (Eunice aphroditois, also known as the sand striker) are real. They lurk, waiting for something to pass by in reach and then they pounce. They get big; at least 3 meters....


22

There are four ways to mitigate bright light which both biology and photography are employing. Diaphragm (pupil). Your species can shrink their pupils to a very tiny size, filtering out as much light as necessary. In addition to that, their eye color should be black, otherwise the light bleeding from the iris would overwhelm the light coming through the ...


16

MAKE SPIKY CLUBS FAST!!! Hello, not-tribe-member. Urk name Urk. Many moons ago, Urk in bad way. Urk kicked out of cave by Thag. Thag bigger than Urk, Thag take Urk spiky club, Urka (Urk wo-man). Urk not able kill deer, must eat leaves, berries. Urk flee from wolves. Today, Urk big chief. Urk have best cave, many wives, many spiky clubs. Urk tell how. WHAT ...


15

I am going to reuse parts of my answer to Anatomically correct Arachne, which is related but not a duplicate. We cannot approach this as if the only way for this creature to exist to exist is in the form of a giant nope spider thing without any modifications to its spider anatomy. That would be silly. We all evolved from very small animals that lived ...


12

From the real world, a sloop the size of your "cog" can be singlehanded for long voyages, even circumnavigations. The reason I specify "sloop" is because the rig is designed to be easy to sail; the number of controls is minimized with only mainsail and jib (you wouldn't bother with a spinnaker in this situation, and they're generally only used for racing ...


9

The limits for wings are pretty straightforward, given that you're trying for some degree of realism. Anything human-sized, with the mass of a human plus however much the wings add, is pushing the limits of flight. I won't call it impossible to fly, not when even larger pterosaurs have done it, but wings big enough to allow more than gliding for a humanoid ...


9

The best candidate would be a snake. Mouthbreeders have big mouths, and generally catch prey whole. There are nothing that feeds by nibbling that holds young in the mouth. There are no insects or non vertebrates that I know of that have big mouths like this. I suspect evolution favored big, gulping mouths first and then selected for mouth breeding after. ...


9

4 meters high and wide and stretching to lengths between 10 to 30 meters is a huge beast. Having to burrow in the sand to move takes quite some energy, as it requires displacing a dense medium. Plus ambushing the prey is another additional effort. A carnivorous diet seems adapt to supply that much energy, however here is the issue: you state they live in ...


9

Silver in the human body does interesting things to our appearance. Most notably, it makes (particularly light skinned people) us look like this: Ingesting colloidal silver (finely particulate silver suspended in water) will eventually turn your skin a metally-blue colour, a condition called argyria. The fluid in your people's blood that carries the ...


9

Star Trek's Vulcans have evolved a nictitating membrane that shields their eyes (Spock's World by Diane Duane and TOS episode "Operation -- Annihilate!"). But this is a bit of an emergency measure. It would also be possible to have a photochromic layer on the cornea, and it could even be active. That is: when hit by ultraviolet rays, or by a strong enough ...


8

First of all it's a matter of size. Newborn fishes and crocodiles are small enough to fit in their parents' mouth. Despite this, some terrestrial animals use their mouth to carry around their babies: never seen a cat or a lion moving around their cubs by gently biting behind their necks? Still, those cubs are too big to fit in the mouth.


8

I think the most important property is a suitable body for the harness connecting the cog to the tug (?) animals, or swim team -- sounds like a bad pun. The cog will need to be a little extra buoyant in the bow to oppose the downward force generated by the swimming monsters. The dermis of most aquatic creatures is not going to accommodate a hemp rope ...


8

Four is a good limit. Most even semi-sentient things should understand something sliced twice is "quartered" into four, for example. If you read any paragraph of well-written text, you are very unlikely to find one which has a specific number larger than four, other than in threads like this where numbers are being explicitly described. In normal speech, ...


7

To me, one body plan is by far the most likely: 6 limbs in a triangular prism. To see why, think of the earliest land-dwelling, limbed animals to evolve on Earth. I'm imagining something like a wide-legged lizard. It's low to the ground; effectively its entire body is in a 2D plane. And this makes sense, since opposing gravity takes work, and evolutionary ...


7

If you aren't familiar with it, I suggest you read "Watership Down" by Richard Adams. Its characters are rabbits who are asserted to be able to count to four, but all greater numbers are eqivalent. There is a word in their language which is sometimes translated as "five" and sometimes as "a thousand". The author is consistent about it, and the dialog ...


6

If your ride is as smart as you are, you are just a passenger. Your crew has nothing to do because their boat has no sails, rudder or oar. It is moved by a giant intelligent mosasaur-like creature. Certain individuals of their kind have an arrangement with onshore humans: they ferry passengers to a destination and in receive get things they need - land ...


6

Polarized Lenses. Making your creature's eyes' lenses polarized would help to block sunlight and glare without having to have extra eyelids or tiny pupils which will be detrimental to its eyesight. Here is a quote about polarization of sunglasses: Today’s sunglasses—with or without prescription—can be modified with a technique called polarization to ...


6

You can miss the counting ability, if you can still compare the relative size of sets. To give an example, you don't need to know that a basket contains 20 apples and another basket 40 apples, if you can tell which basket has more apples than the other. More often than not what matters is the relative size, not the absolute size. Other examples: Is that ...


5

/Why worry about the drop off of a skyscraper if you can just fly off? Why figure out how you’re going to climb up to the top of this balcony is you can just fly up to it? (/ Go with it! He does not worry about the drop off. He worries about how exposed to gunfire he is while flying away from the people who chased him off the drop off, or worries about ...


5

A carnivorous worm is not unlike a snake and we have data about what snakes eat (they're all carnivores). Giant snakes may only eat 4 to 6 times yearly. (ref) And snakes can lower their metabolic rates, become more protein efficient, and survive months without any food at all. Though most snakes eat every 5-14 days. The largest snake in the world is the ...


5

Do you mean "How to evolve?" literally? Evolution isn't something that tries to achieve a goal. In general, it is a meaningless random process that takes a large gene pool of many variations of genes, and then kills off individuals that lack the specific genes that will help them to survive long enough to produce children. The number and frequency of ...


5

Take a quick glance at a close group of 5 things. Your brain can just tell, without really trying, that there are 5 things there, right? It's even easier with four or three, especially if the objects are arranged in familiar patterns, like a square or a quincunx (i.e., the pattern of dots for the number 5 on a die). Now, take a quick glance at a group of ...


5

It's not possible for your creatures to not be able to comprehend large vs small groups. Even bees can do this. Waggle Dance: Purpose is to explain the distance, direction and desirability of a nectar source farther than 10 meters. In this dance, the bee makes two semi-circles and then runs the diameter of the circle. The straight side of the semi-...


5

Humans do not automatically count. In fact even up to the medieval era and probably beyond many people never had any numerical education. In fact it might still be practiced in large area's of Africa (1). The idea is to simply tie a knot for every count. You've got 18 cows? Well you have one knot per cow (or in case of more advanced area's like wild-west ...


5

The Roc would be able to fly at high altitudes, up to 15,000 feet Many birds do this already. I remember reading that a flock of I think geese was seen by the crew of a commercial flight at cruise height, and they go 24000 feet and above. The Roc would be able to maintain altitude for long periods of time, rarely returning to the Earth to land. ...


5

There are organisms which can essentially "eat" minerals, chiefly lithotrophic bacteria. These microbes may get their energy from: Ferrous iron Sulfur Hydrogen Nitrite Ammonia Ammonium Sulfide Phosphite Carbon monoxide Potassium Hydrogen sulfide To name a few. However, there are no complex multicellular organisms which are themselves lithotrophs. There are ...


4

Physically arduous (which they are. Birds have to eat lots of food). Take-off takes long. Some birds rarely touch earth because taking off is a serious issue. This is coupled with being physically arduous. Mentally taxing. You need to pay attention to each detail of muscle movement, in a non-intuitive way. Then you can't pay attention to anything else. ...


4

Sadly, it's physically impossible to build an endotherm that breaths water nomatter how hard you try. In best case scenario, oxygen saturation of water reaches about 10 milligrams per liter. Consider the oxidation of beryllium metal in oxygen, one of the most efficient heat generation method possible with a standard enthalpy of formation of -599 kJ/mol. ...


4

It isn't important at all. We call them the odd-toed ungulates, but really it's just a group of related animals that, for the most part, have odd numbers of toes. This tends to happen because the common ancestor of these animals placed most of its weight on one particular digit, so unless there's a reason not to its descendants tend to have the other toes ...


4

Caveat: I'm not an evolutionary biologist. It probably has something to do with the fact that non-aquatic animals breathe through our faces, whereas most aquatic animals have gills. My (cursory) reading on mouthbrooders indicates that most either do not feed while brooding or feed very little. This indicates to me that the mouth is almost or completely ...


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