how do fishes communicate with each other?
542087
The ocean that marine fishes live in covers 71% of the earth's surface, making a huge body of water in which they swim. As a result of this expansive habitat, fishes use sound to help in both finding mates and protecting the territory in which they live.\n\nFishes also use sound to defend their territory and warn other aquatic animals of their presence in the area
1035087
Oxygen is carried in the blood.  The oxygen transfers from the atmosphere to your blood through an exchange in your lungs...\n\nA fish's gills accomplish the same thing, but they get the oxygen from the water.
35394
From what I know...no one really knows how the majority of sponges to communicate. The hexactinellids sponges are syncytial and most scientists believe that have chemical communication. A hormone or something is given off by one sponge and picked up though the water it filters all through the body, and so all cells exposed receive the signal to release gametes.
392040
Hope this sheds some light on it jessica.\n\n\nREPRODUCTION\n\nMost fishes are egg-layers, but many bear living young. Live-bearing fishes may be ovoviviparous, in which the eggs essentially simply hatch within the female, or viviparous, in which the unborn young are supplied nourishment through the mother's tissues. In some ovoviviparous fishes the embryo develops in the egg while the egg is still within its follicular covering within the ovary, and ovulation (or release of the egg) and birth occur at the same time. In other ovoviviparous forms the eggs are released from the protective follicles into the cavity of the hollow ovary, where development continues. In some viviparous fishes the walls of the egg follicle are in intimate contact with the embryo, supplying it with nourishment. In the viviparous sharks, a part of the oviduct, or egg channel, is developed into a uterus, where the modified yolk sacs of the young are closely joined to pockets within the uterus.\n\nIn live-bearing fishes and in some egg-layers, fertilization occurs internally, and methods have been evolved for introducing the sperm into the female's body. In sharks the pelvic fins of the male are modified into intromittent organs called myxoptergia, and in the male topminnows the anal fin is modified into a similar-functioning intromittent organ called the gonopodium.\n\nAt least three modes of reproduction--heterosexual, hermaphroditic, and parthenogenetic--are found in fishes. In the most common form, heterosexual reproduction, there are separate male and female parents, but even here there is considerable variation. In some live-bearing fishes, the female is able to store sperm for up to 8 or even 10 months, and this sperm is used to fertilize new batches of eggs as they develop. In some cases, a female may carry sperm from several males at once.\n\nIn hermaphroditic reproduction, a single fish is both male and female, produces both eggs and sperm (either at the same time or at different times), and mates with other similar hermaphroditic fishes. External self-fertilization occurs in one hermaphroditic fish, which sheds egg and sperm simultaneously. In another, internal self-fertilization may occur. In certain fishes there is a time sequence of hermaphroditism, young fishes reversing their sex as they grow older.\n\nIn parthenogenetic reproduction, unfertilized eggs develop into embryos. This is known to exist in at least one fish species, Poecilia formosa, of the Amazon River; however, even though development proceeds without fertilization in some of these females, mating with a male is still required to stimulate egg development.\n\nParental care also shows great diversity. Some fishes, like the Atlantic herring, form huge schools of males and females and freely shed their eggs and sperm (milt), and then abandon the eggs. Other fishes build nests and care for both the eggs and newly hatched young. Others have evolved methods of carrying the eggs with them, commonly in their mouths, but also in gill cavities or in special pouches on the body.
586867
Plants use chemical signals to communicate. For example, acacia trees in Africa release chemicals into the air when fed on by giraffes. This alerts the tree and surrounding trees to produce toxins in the leaves which eventually deter the giraffe from feeding too much on the one tree. So technically you could talk to your plants by using chemical signals. Animals also use chemical signals (pheromones) to communicate.
1074437
I found this article on parasites and fish.  Hope it helps.\n\nhttp://www.charkbait.com/article/RAPC2.htm
865523
All fish swim with their mouths open at least a little. This is a big part of how water gets to their gills so they can take in oxygen and get rid of carbon dioxide.
593014
The gill works by providing a surface where the water (which has dissolved oxygen) comes into contact with the blood of the fish. The blood circulation within the gill is arranged in such a way that it flows in opposite direction to the flow of water (=countercurrent arrangement). Because oxygen will tend to flow (diffuse) from the site of highest concentration to the place of lowest concentration, this arrangement ensures that oxygen will always flow from the water into the blood.\nOxygen is not as abundant in water as it is in the air, so for aquatic animals, oxygen concentration is a major limiting factor. The best way to ensure that enough water is "scanned" for oxygen at the gills is providing a really large surface area for gas exchange. Thus, each gill is formed by filaments. Each filament has secondary lamellae that rise perpendicularly to the surface of the filament. The total surface area is extremely large with respect to the volume of the gills. \nGas exchange occurs at the secondary lamellae, and it's here where you can see the countercurrent circulation. \nSee picture here:\nhttp://www.fishdoc.co.uk/images/Gill_-_gross_view.jpg\n\nThe water is passing between the gill arches, toward the medial part of the gill, and the blood is circulating in the exact opposite direction. Thus, the water always encounters blood that has less oxygen, and diffusion of O2 continues toward the blood. See this diagram for an easy visualization:\nhttp://www.marinebiology.org/images/countercurrent.GIF\n\nI hope this helps.
474094
No, they are not fish...the following was taken from Yahoo!\n\nhttp://ask.yahoo.com/ask/20030507.html\n\nTrue fish are vertebrates and belong to the Chordata phylum of the animal kingdom. This group encompasses most of the animals we are familiar with, such as mammals, birds, reptiles, and amphibians, as well as humans. \nStarfish, or sea stars as they are sometimes called, are invertebrates, meaning they have no backbone. These spineless (and we mean that in the best possible way) creatures belong to the spiny-skinned phylum of animals known as Echinodermata and the class Asteroidea.
1101435
Smell, or olfaction, as scientists call it, is an important sense for many fish. Those little holes that look like nostrils are called nares. Nares don't lead to the throat the way nostrils do in mammals, but open up into a chamber lined with sensory      pads. Not all fish move water in and out through these nares in quite the same ways, but key to a strong sense of smell for fish is the ability to move water rapidly over these sensory pads. Some fish can pick up chemical signals when immobile by      pumping water through their olfactory system via tiny hairs called cilia. Other fish can pump water by a muscular movement. Some fish, such as smaller species of mackerel, have an olfactory system that requires them to swim in order to get water      moving through their nares. When the sensory pads pick up chemical signals, they transmit them to the fish's forebrain, which interprets the signal and incites the fish to respond appropriately.
1055343
It is sure that animals are able to produce sounds.\nAlso they have a "vocabulary" (dogs for example make\n5-6 diferent sounds meaning different things.\n\nThis is not speach!!!!\nTalking means thousands of diferent "sounds" meaning\nthousands of different things. Talking is complex and\nneeds a complex brain. Thats why they dont talk.
1062365
no, because fish have gills (breathe on the outside) unlike us we have lungs in the inside.  In my aquarium tank I have a small mouth Bass & Yellow Perch, when i feed my bass minnows he would have three minnows in it's mouth (minnows literally sticking out it's mouth)/ my perch as well.  They will swim around with half a minnow sticking out it's mouth and act like it's no big deal.  You will see this with bluegill they will take the worm and swim around with it hanging out it's mouth.  I just feed my fish (thanks for reminding me) and I took pictures so if you want to see them just e-mail and I'll send it to you.  \n-About the dead smaller fish stuck in it's throat some fish I catch may puke up fish due to exhaustion.  When i go fishing for walleyes and northern pike I've had them cough up fish on me.  I've had bass do the same.  \n-Death? He could have died due to foul hooking (not meaning snagging) but if it hook in the middle or back of the throat can kill any fish especially if it's kept out of the water to long, just cut the line and release.  It doesn't work out all the time.
3708
ants navigate and communicate largely by sense of smell.  they leave behind chemical markers that signify certain things - "food this way" or "danger" or whatever.  (this can be tested by you!  if you find an ant trail, put down a piece of paper and the ants will be lost!  eventually they'll make a new trail across the paper - which you can then move and manipulate where they go.)  \n\nthe antennae on their heads are their smell organs - so when they meet, the two ants communicate by smelling each other - kinda like dogs.
691160
Fresh water creates a hypotonic environment for aquatic organisms. This is problematic for some organisms, whose cell walls will burst if excess water is not excreted. Some protists accomplish this using contractile vacuoles,[2] while freshwater fishes excrete excess water via the kidney.[3] Although most aquatic organisms have a limited ability to regulate their osmotic balance and therefore can only live within a narrow range of salinity, some fishes have the ability to migrate between fresh water and sea water.\n\nAs with many aquatic animals, most fishes release their nitrogenous wastes as ammonia. Some of the wastes diffuse through the gills into the surrounding water. Others are removed by the kidneys, excretory organs that filter wastes from the blood. Kidneys help fishes control the amount of ammonia in their bodies. Saltwater fish tend to lose water because of osmosis. In saltwater fish, the kidneys concentrate wastes and return as much water as possible back to the body. The reverse happens in freshwater fish, they tend to gain water continuously. The kidneys of freshwater fish are specially adapted to pump out large amounts of dilute urine. Some fishes have specially adapted kidneys that change their function, allowing them to move from freshwater to saltwater
32525
Most all fish spend time in an energy-saving state that can be called\n"rest", and we might even call their behavior "sleep", though it is probably \ndifferent than "sleep" in most land\nanimals.  Many fish, like Bass and perch, rest on or under logs at\nnight.  Coral reef fish active in the day, hide and rest in crevices\nand cracks in the reef to avoid being eaten at night.\nThe resting behavior of fish is very different from their behavior the\nrest of the day. Many minnows, for example, which are very active in\nschools during the day, scatter and remain motionless in shallow\nwater at night.  Many fish "rest" or "sleep" during the day and are\nactive at night instead, but almost all fish sleep.\nThere are some animals that never stop swimming, like many species of\nshark, however, they HAVE to keep moving to push water through their mouths\nin order to breathe, and they may still sleep while moving,\nwe just don't know yet.
399011
The spawning fish is a Grunion.\n\nOn the second question I can't help you.
235479
Yes, male fishes have paired testicles inside their bodies. Fish sperm looks like a viscous fluid; fish spermatozoids don't look much different from our own (I'd say more like a tadpole than a fish).\nHere's a photograph of a spermatozoid from a fish:\nhttp://cmif.osu.edu/images/department/transmission_3.jpg