What is a Coelacanth, and how thus it fit into the evolutionary theory?
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It is a lobe-finned fish; the evolutionary relationships of the coelacanths to the other two living groups of lobe-finned fish (Sarcopterygii), the lungfish (Dipnoi), and the land vertebrates (Tetrapoda) remain debated until today. Since its discovery, many comparative morphologists and paleontologists considered the coelacanth to be the closest living relative of the land vertebrates, although the lungfish were historically thought, and continued to be thought by some researchers, to hold that claim. More recently, however, several analyses began to challenge the sistergroup relationship between the coelacanth and the tetrapods, first on morphological and paleontological grounds and later based on molecular phylogenetic analyses.
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I don't think any such monsters exist but yes maybe some ancient reptiles or other species(like coelacath which was thought to be extinct) maybe there.
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If you do your research you will see that the concept of time in mens eyes compared to Gods eyes are probably two very different things!\nwe are told to go to the fossil record for final, conclusive proof that evolution really did take place. You might imagine we would find a succession of fossils, for example, starting with shellfish, in which the hard shell gradually turns into a covering of scales, while part of it turns inside and grows into a backbone. At the same time, successive fossils would be developing a pair of eyes and a pair of gills at one end and a finny tail at the other. Finally, lo and behold, we would have a fish!\n\nBut a fish would not stay a fish. Coming on up in the geologic column of sediments, we would expect to find fish changing their fins into legs, with feet and toes growing out of them, and their gills into lungs. Higher up, we would no longer find their fossilized remains in old seabeds but buried in dry land deposits. And in other fish, their forefins would be changing into wings and their back ones into legs with claws. Their scales would change to feathers and they would grow a horny beak around their mouth. And, presto! the magic of evolution would have given us reptiles and birds. So we could line up intermediate forms exhibiting transitional features between every ancestral species and each type of their progeny.\n\nIs that what we really find? Of course not! That would be an evolutionist’s dream. Darwin himself was the first to bemoan the extreme imperfection of the fossil record. But he was hopeful that time would supply the transitional forms between species—missing links, they came to be called. These would vindicate his faith in the process of evolution by natural selection.\n\nBut these hopes have not been realized. What does the record actually show? Each new kind of plant or animal—fern, shrub, tree, fish, reptile, insect, bird, or mammal—appears suddenly in the geologic column. Beginning immediately above the lifeless sediments of the Azoic era, the Cambrian layer carries an abundance of fossil crustaceans and shellfish, in great variety, already fully developed. Plants with woody stems appear suddenly in the mid-Paleozoic. Fossil wood has not been found in lower strata but is abundant in all later ages. Large collections of insect fossils have been found in upper Paleozoic rocks, fully developed and in great diversity, but none have been found in earlier strata. Early in the Cenozoic era, modern types of mammals make a sudden appearance; there is no record of their evolution from earlier types.\n\nThis is the repeated testimony of the fossil record: Sudden appearance of new kinds of plants and animals—no precursors. Does this not suggest, to the unprejudiced observer, the creation of these new kinds in successive ages, rather than continuous evolution?\n\nPermanence of Species\n\nBiologists have devised an elaborate system for classifying different species. Naturalists continue to find species that are different from those already classified, and those are fitted in between the others. Extinct species, represented by fossils, also have been assigned places in the classification. Different fossils continue to turn up that have to be put between others in the system. The evolutionists call these transitional species, a word that implies a temporary existence, during which it falls between an older species and a new one that is to appear. Even calling them transitional reveals a bias in logic. A neutral expression would be “intermediate” forms.\n\nMuch emphasis is put on the search for these “transitional” forms. As an example they point to the lungfish, which has gills for taking in oxygen when in water and also a bladder that serves as a lung for breathing when out of water. This is supposed to have marked a stage in evolution between fish and reptile. But there is a snag in the logic. The lungfish did not change into a reptile. It is still living today, the same
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Clown fishes are indeed Actinopterygii, or fishes with skeletal bones.  (In ichthyology, that is the biology of fishes, the plural fishES is actually alright to use when you speak of more than one species.  If you are talking about more than one individuals of one species, you use fish.)  To be exact, they are a member of the largest group of bony fishes, the teleosts.  \n\nBut from a biologist's point of view "fish" is not really a true biological category - or as we say in biology, no real monophyletic group.  It's one of those names under which all animals are subsumed that have a certain shape, that have fins, and that have gills.  But the chondrichthyes (the cartilageous fishes) are very different from the teleosts; it is almost as if you compared a mammal like a mouse, with gecko.  Most ichthyologists (or fish biologists) would therefore say that clown fishes are really teleosts.\n\nThe interesting thing about the different species of clown fish is that they change their sex throughout their life.  For example, the blackfinned clownfish (Amphiprion percula) is protandrous, which means they start out their lives as males and then later in life turn into females.  What determines the exact timepoint of this change is actually social behavior.  Normal Amphiprion percula live in symbiosis with an anemone (meaning the clownfish protects the anemone against certain predators, while the anemone offers protection to the clownfish between its tentacles).  Usually there is one female with a harem of a few males in the anemone.  When the female dies the male of the highest rank begins to change into a female.  This change is controled by hormones, and the hormone levels change in response to the altered social condition (i.e., the female being gone).  There are other hermaphrodite species, like the blue-headed wrass, that start out as females and then turn into males, a strategy called protogynous.  \n\nWell, that bit on hermaphrodism was more than you asked about.  But it's a cool bit, and so I thought I'd throw it in here.  Hope you liked it...
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Oh no, not this question again. Why doesn't anybody use the Search button?\nLet me address two separate issues (the first part is modified from another answer):\n1) The pattern of evolutionary processes that can be seen (in the fossil record and living species)can be of two types: \nIn _anagenetic_ (meaning "that generate upward movement") events, an entire population evolves in one direction and becomes so different that at some point the people who study it give it a different name. This is encountered in paleontological research and the decision to separate one from the other is ultimately arbitrary. \n_Cladogenetic_ (meaning "that generates branches") events entail a population that splits into different sub-groups; each of these then evolves independently from the others. We share A COMMON ANCESTOR with living apes, but we have not evolved from them directly. \nOur direct ancestors are fossil hominid species. \nAll the species that are living today have their separate evolution and history; also they all (including humans) share common ancestors from which they (we) have inherited our common traits. And apes have their own ancestors that are closer to them than to Homo sapiens; the fact that apes are our closest living relatives does not exclude the existence of more related _extinct_ relatives.\n\n2) What you're stating is one of the arguments that many creationist use, namely, that change within a species (adaptation, i.e. microevolution) is possible (they are astute in not denying this, because the proofs are overwhelming!), but a species cannot transform into another (macroevolution). \nThis is based on a mistaken concept of "species". Most people think in terms of the biological species concept, which is based on reproductive isolation. That is, individuals of each species cannot hybridize succesfully with individuals of other species. However, there is not a single path for the rise of the mechanisms for recognition or isolation that we perceive as the "real boundaries" of a species (see second link for an interesting discussion here at Y!Answers). What the taxonomist calls a species may respond to different species concepts (such as morphological, evolutionary, biological (isolation), paleontological, recognition, etc,), and there are many examples of populations in which speciation (total isolation) is on the way, and there's a thin line between "subspecies" or "geographical races" and valid species (just ask an expert in systematics, which I am not). \nEvolutionary processes are long-term phenomena, and it may seem that there are "evolutionary leaps" from one species to the other. But although there are particular cases of "instantaneous speciation", most of the "leaps" are due to the fragmentary nature of the fossil record. So many populations become extinct or become something else and their former existence is not recorded anywhere! But although the record is fragmentary, life is continuous.\n\nSorry for the lengthy answer, I hope you find it useful.
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Er... the theory of evoltion?  It's just a theory though.  Lots of loop holes.  :)
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The phylogeny of snakes is poorly known due to the fact that snake skeletons are typically small and fragile, making fossilization unlikely. It has however been generally agreed, on the basis of morphology, that snakes descended from lizard-like ancestors. Recent research based on genetics and biochemistry confirms this; snakes form a venom clade with several extant lizard families.\n\nRecent fossil evidence suggests that snakes directly evolved from burrowing lizards, either varanids or some other group. An early fossil snake, Najash rionegrina, was a two-legged burrowing animal with a sacrum, fully terrestrial. One extant analog of these putative ancestors is the earless monitor Lanthanotus of Borneo, although it also is semi-aquatic. As these ancestors became more subterranean, they lost their limbs and became more streamlined for burrowing. Features such as the transparent, fused eyelids and loss of external ears, according to this hypothesis, evolved to combat subterranean conditions (scratched corneas, dirt in the ears). According to this hypothesis, snakes re-emerged onto the surface of the land much as they are today. Other primitive snakes are known to have possessed hindlimbs but lacked a direct connection of the pelvic bones to the vertebrae, including Haasiophis, Pachyrhachis and Eupodophis) which are slightly older than Najash.\n\nThe alternative hypothesis, based on morphology, suggests that ancestors were related to mosasaurs — extinct aquatic reptiles from the Cretaceous — which in turn are thought to have derived from varanid lizards. Under this hypothesis, the fused, transparent eyelids of snakes are thought to have evolved to combat marine conditions (corneal water loss through osmosis), while the external ears were lost through disuse in an aquatic environment, ultimately leading to an animal similar in appearance to sea snakes of today. In the Late Cretaceous, snakes re-colonized the land much like they are today. Fossil snake remains are known from early Late Cretateous marine sediments, which is consistent with this hypothesis, particularly as they are older than the terrestrial Najash rionegrina. Similar skull structure; reduced/absent limbs; and other anatomical features found in both mosasaurs and snakes lead to a positive cladistical correlation, though some features are also shared with varanids. Supposedly similar locomotion for both groups is also used as support for this hypothesis. Genetic studies have indicated that snakes are not especially related to monitor lizards, and (it has been claimed) therefore not to mosasaurs, the proposed ancestor in the aquatic scenario of their evolution. However, there is more evidence linking mosasaurs to snakes than to varanids. Fragmentary remains that have been found from the Jurassic and Early Cretaceous indicate deeper fossil records for these groups, which may eventually refute either hypothesis.\n\nThe great diversity of modern snakes appeared in the Paleocene, probably correlated with the adaptive radiation of mammals following the extinction of the dinosaurs.
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Snakes, lizards and amphisbaena (which most of you won't have heard of, but they're neat!) have "hemipenes", basically dual penises.  It has no real advantage, it's just how they evolved.  They only use one at a time.  It's just a different way to evolve a penis structure on a bilaterally symmetrical animal.
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It could be both my personal opinion is that, if nessie exists, it is a plesiosaur, an aquatic animal that lived at the time of dinosaurs.  Impossible, you say? think again,many species that have been previously thought to be extinct have been found recently, like the coleocanth, a prehistoric fish.
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Go here for a great picture of a baracuda and description: \n\nhttp://library.thinkquest.org/22403/data/medium/species/barracuda.html
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Good question!\n\nOne of the coolest adaptations that deep sea organisms have is called bioluminescence.  This allows the organisms to actually produce their own light!  Many of these organisms use the light to attract mates.  Predatorial fish take advatange of this fact, and can lure in unsuspecting prey by simply producing light (in other words, they pretend to be a potential mate).\n\nThe depths of the ocean can be extremely cold, and food can be quite hard to find.  So these organisms have a tendency to gravitate towards sources of food (such as decaying matter) and sources of heat (watervents).  By simply 'coming together' to look for food and heat, they make it much easier to find a potential mate.
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I know of no cases in which the DNA of obligate\ntroglobites have been compared with their surface\ndwelling relatives, though such may exist.  There\nare a few intermediate cases known in which the\nsurface and cave living individuals of a given\norganism seem still to be the same species, but\nin most the separation seems to be complete.\n\nThe really cave adapted species can not survive\noutside the cave habitat and are therefore\nisolated almost completely from their surface\nrelatives.  With this isolation, and the strong\nselection pressure exerted by the difficult cave\nenvironment,it is almost certain that the two\npopulations would diverge rapidly to the point of\nbecoming different species.
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You are right.\n\nCenturion: I hope that you only are asking this question sarcastically, in order to give an example of the silly questions that creationists ask, so nobody has to explain that obviously species take separate evolutionary paths, based on their environment, so that the same species in different environments will eventually evolve into different species.\n\nUnknown: What do you mean by a fossil of a creature turning into something else?  That doesn't really make much sense, seeing how all creatures are in the process of turning into "something else" - we just don't know what the future of evolution holds.  Haven't you heard about the recent discovery of the fossil of the "fish" which helps to provide evidence of the transition of animals from water to land?  I don't really know what you mean by saying that there are no "missing links" - there are thousands of them!  I just ahve the feeling that no number of missing links would be sufficient.  Between any two species it will always be possible ask for a "linking" fossil, and since there cannot be an infinite number of fossils, it will always be theoretically possible to say that no missing links have been found.\n\nmamcrackin: http://www.sci-tech-today.com/story.xhtml?story_id=12200044CLXE\nsee my comment above that no number of misssing links will ever be able to "prove" evolution.  If half-man/half-animal were found (and they have been, just look at all the fossils of the earlier human species) creationists would just ask for 3/4 man, 1/4 animal fossils, and then 7/8 man, 1/8 animal, and so on.  \n\nindiebaptist: Her point is that while there would be fish fossils evenly dispersed throughout the layers of earth, non-aquatic animals would be clumped in one layer - the layer during which the flood occurred.  This is not what we find when looking at the fossils in the layers of earth.  The great flood was also gods way of killing a lot of animals who had done nothing to deserve that punishment. by the way, hovind's PhD (from a non accredited school) is in christian education, not biology or any other science. http://en.wikipedia.org/wiki/Kent_Hovind  \nI really have to wonder where you are getting your facts from.  Darwin wasn't a lawyer, and even if he was, you are citing the work of someone trained in christian education, not science in order to support your belief.  How is that any better?  In any case, Darwin was formally trained to be a clergyman, but studied a lot of the natural sciences on the side. http://en.wikipedia.org/wiki/Charles_Darwin\nRegardless of darwin's training, his theories must stand on their own merit, as his has done, and not on the credentials of their creator.
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That is not a good question. A cladogram expresses the ancestor-descendant relationships by means of _branches_, not by means of an ascending or ordered system. Thus, a goldfish would not come "before" a horse, nor a lamprey before a platypus. All the animals in your list do not even belong to a single nested group of taxa.\nThe sparrow is more related to the crocodile, the horse with the human and they in turn with the platypus, but all them, as well as lampreys, frogs, goldfish,  have their own evolutionary histories and their phylogenetic relationships are more complex than that.\nTell that to your teacher!
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Here you go, check this out.\n\nhttp://evolution.berkeley.edu/
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http://www.talkorigins.org/indexcc/CB/CB928_1.html\nhttp://www.talkorigins.org/indexcc/CB/CB928.html\n\nSome brief information there. More explained in Origin of Species for example.
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The Sarcopterygii, in particular the Rhipidistian Osteolepiformes such as Panderichthys\n\nPanderichthys had a number of morphological traits which place it in the lineage which gave rise to the tetrapods:\n\n- fin bones which fit the pattern of humerus, ulna and radius (forelimb) and femur, tibia, fibula (hindlimb) seen in all tetrapods\n\n- brain case so similar to early amphibians (Icthyostegans) that it was originally classified as one\n\n- lungs and choanate nostrils, but still possessed gills as well\n\n- teeth with infolding enamel identical to the earliest tetrapods\n\n- a spiracle (which becomes modified in later tetrapods into the stirrup bone of the inner ear)