do any fish have eyelids?
310529
Fish don't have eyelids — they don't need them underwater because dust can't get in their eyes.
1324654
They can be fin nippers, so they shouldn't bother the neons, lamp eyes and the shrimp, which don't have long fins or in the case of the shrimps, any fins. As long as the guppies don't have giant tails (like some variations), it should be okay.
1026839
These fish have muscular bodies, ossified bones, scales, well developed gills and central nervous systems, and large hearts and kidneys. Mesopelagic plankton feeders have small mouths with fine gill rakers, while the piscivores have larger mouths and coarser gill rakers.
1184077
["Males often have bright red, pink or orange eyes. Females tend to have brown eyes, and when she does have red eyes, it's a darker red than the males. ... ", 'Male ornates often have a greenish or yellowish head. ... ', 'Male three-toed box turtles sometimes have a dark red head.']
1187198
Find out if your fish is female. Also, the female pectoral fins (located just behind the gills) are shorter and rounder than those on males. Additionally, goldfish will generally not lay eggs until they are at least one year old.
1209705
Eyes. ... The eyes are very small, and they contain Spiracles behind and above them. Unexpectedly, the majority of these sharks are blind due to the fact that they have parasites hanging from their eyes. These pinkish-white parasites are called copepods, and they attach themselves to the Greenland sharks' cornea.
365790
Fish eyes contain many of the same components as human eyes, but they are structured and used differently. Fish have a cornea or outer covering, a lens for “taking a picture,” an iris for adjusting light, a retina containing light-sensitive cells and an optic nerve for translating the picture to the brain.
639988
Crested geckos do not have eyelids. Instead, a transparent scale, or spectacle, keeps each eye moist, and the geckos use their tongues to clear away debris. Like the closely related Rhacodactylus geckos, crested geckos have webbed legs and digits.
498996
There are many ways to tell the two apart, but the easiest way is to look for “barbels” or “whiskers” near the mouth. Koi will have these barbels on the lips, while goldfish will not. Also, goldfish tend to be much smaller and exhibit more variety in body shape than koi.
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No, fish do not get “sad” if another fish dies. Fish do have a brain that is capable of some type of “emotion” but not to the extent that humans feel. They don't feel anything like sadness, but may feel something to a smaller extent. ... Another study indicated that they feel something similar to pain.
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Fish With Transparent Head Filmed. Photographed 2,000 feet deep in the Pacific Ocean off the California coast, the Macropinna microstoma, known as the barreleye fish, is small and dark with large fins, a tiny mouth, and unusual 'barrel' eyes under a transparent dome.
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Like human eyes, land mammals and fish have eyes that function almost like cameras. Their eyes contain a lens and pupil, just like ours. Their eyes use light-sensing cells that work with the lens, pupil and cornea to take a picture with the eye.
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Guppies, live bearers themselves, and zebra danios get along well with many of the common types of live-bearing fish. ... Be careful when adding sailfin mollies or other fish that have long fins or tails and are relatively slow swimmers, because the guppies and danios may nip at the fins.
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['Live in water their entire lives.', 'Vertebrates have a backbone, and some cartilaginous fish have vertebrae made of cartilage rather than calcium-hardened bone.', 'Gills, which are slits on both sides of fish that allow for respiration, or the exchange of oxygen and carbon dioxide.']
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No, in the fact that none of the fish references in the Bible specifically refer to the fish as tilapia. Yes, in the probability that some of the fish referenced were likely tilapia as they were a common fish from the Sea of Galilee and are referenced in Egypt as well.
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You should avoid keeping them with long-finned fish such as Sailfin Molly fish or Elephant Ear Guppies – your Danios will nip at the tail fins of these fish. This fin nipping behavior can be a sign that either, the tank is too small, or, the Zebra Danio shoal is too small.
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These creatures are born with two eyes of the same size and dark color. But during its juvenile years, one of the cockeyed squid's eyes transforms, growing until it bulges and turns yellow. ... Meanwhile, the smaller normal black eye has its own job: It scans the water below the cockeyed squid for any bioluminescence.