Describe how the Mollusks have evolved into one fo the most sucessful phyla on Planet Earth.  PLZ!!!?
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They have evolved and adapted to just about every Biome and environment on Earth.  They are found deep in Ocean on on Mountains, in frigid cold water and on warm tropical islands.  They are defined as successful because of their ability to evolve to so many places.  (Also, they're physically tough, often with an outer shell and a compact muscular body and some are decomposers feeding off dead animals, while others attack living organisms)\n\n-Science methods teacher trainer
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Here you go, check this out.\n\nhttp://evolution.berkeley.edu/
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>>>>>They have never found any.\n\nThere are many transitional fossils.\n\n\nThe only way that the claim of their absence may be remotely justified, aside from ignoring the evidence completely, is to redefine "transitional" as referring to a fossil that is a direct ancestor of one organism and a direct descendant of another. However, direct lineages are not required; they could not be verified even if found. What a transitional fossil is, in keeping with what the theory of evolution predicts, is a fossil that shows a mosaic of features from an older and more recent organism.\n\nTransitional fossils may coexist with gaps. We do not expect to find finely detailed sequences of fossils lasting for millions of years. Nevertheless, we do find several fine gradations of fossils between species and genera, and we find many other sequences between higher taxa that are still very well filled out.\n\nThe following are fossil transitions between species and genera:\n\n   1. Human ancestry. There are many fossils of human ancestors, and the differences between species are so gradual that it is not always clear where to draw the lines between them.\n\n   2. The horns of titanotheres (extinct Cenozoic mammals) appear in progressively larger sizes, from nothing to prominence. Other head and neck features also evolved. These features are adaptations for head-on ramming analogous to sheep behavior (Stanley 1974).\n\n   3. A gradual transitional fossil sequence connects the foraminifera Globigerinoides trilobus and Orbulina universa (Pearson et al. 1997). O. universa, the later fossil, features a spherical test surrounding a "Globigerinoides-like" shell, showing that a feature was added, not lost. The evidence is seen in all major tropical ocean basins. Several intermediate morphospecies connect the two species, as may be seen in the figure included in Lindsay (1997).\n\n   4. The fossil record shows transitions between species of Phacops (a trilobite; Phacops rana is the Pennsylvania state fossil; Eldredge 1972; 1974; Strapple 1978).\n\n   5. Planktonic forminifera (Malmgren et al. 1984). This is an example of punctuated gradualism. A ten-million-year foraminifera fossil record shows long periods of stasis and other periods of relatively rapid but still gradual morphologic change.\n\n   6. Fossils of the diatom Rhizosolenia are very common (they are mined as diatomaceous earth), and they show a continuous record of almost two million years which includes a record of a speciation event (Miller 1999, 44-45).\n\n   7. Lake Turkana mollusc species (Lewin 1981).\n\n   8. Cenozoic marine ostracodes (Cronin 1985).\n\n   9. The Eocene primate genus Cantius (Gingerich 1976, 1980, 1983).\n\n  10. Scallops of the genus Chesapecten show gradual change in one "ear" of their hinge over about 13 million years. The ribs also change (Pojeta and Springer 2001; Ward and Blackwelder 1975).\n\n  11. Gryphaea (coiled oysters) become larger and broader but thinner and flatter during the Early Jurassic (Hallam 1968).
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I'd like to think that you're asking this question with an earnest wish to get good informative answers. If that is the case, I invite you to see the link that Kurdiatcha left, or to do a web search for the term, or else, to read some good Evolution textbooks such as Ridley's "Evolution" or Freeman & Herron's "Evolutionary analysis", or Futuyma, or Stephen Jay Gould if you want something more entertaining.\nIf that is not the case, I'm not bothering anymore *sigh*
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This is an excerpt from the referenced website:\n"Recovery of diagnostic ankle bones in the skeletons of primitive protocetids during our field work in Pakistan in 2000 confirmed their derivation from Artiodactyla (the mammalian order including cows, deer, hippos, etc.), and showed convincingly that whales did not originate from mesonychid condylarths as Van Valen hypothesized (and we had expected)."\n\nHope this helps.
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You are looking for the Cnidaria corals I believe. In the early Paleozoic (cambrian to silurian) they diversified into tabulate corals, rugose corals, and heliolitid corals. All these forms were wiped out at the end of the Permian Period, in a mass extinction event that claimed something like 95% of all marine invertebrate species.\n\nDescriptions of these types of corals are linked in this page:\nhttp://www.ucmp.berkeley.edu/cnidaria/cnidariafr.html\n\n\nTHis page may also be a big help to you:\nhttp://www.paleoportal.org/fossil_gallery/taxon.php?taxon_id=55
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One of the most significant changes that occurred in early vertebrate evolution is that of the development of jaws.  Jaws first appeared generally in gnathostomes, but more specifically in shark like ancestors called placoderms. Present day sharks are the representative group of early vertebrates with jaws. \n\nThere are two theories on why jaws first evolved. One theory ("new skull") states that jaws evolved to aid in more efficient feeding and feeding on larger prey, which increased metabolic rate and thus allowed for a more active lifestyle. The other theory, "new mouth", states that jaws evolved to allow for more efficient ventilation mechanisms, which allowed for a higher metabolic rate and thus a more active lifestyle. Secondarily in this scenario, jaws also aided in more efficient feeding.\n\nAlso, it should be noted that many animal groups that evolved prior to the early vertebrates has pharyngeal slits or pharyngeal openings. That isn't really a characteristic specific to vertebrates as several pre-chordate and chordate groups have pharyngeal/gill slits.
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This all comes down to the way that vertebrates evolved, and it is a classic example of evolution producing a workable though complicated design that no intelligent designer would ever produce unless she were on drugs.\n\nTo explain let’s go back to the very earliest chordates. We are going back here to a time before our ancestors were fish, before they even had backbones. These things existed as essentially free-swimming worms a few inches long. No fins, no jaws, not even a real mouth, no limbs of any sort, just a body and a head. Every body segment aside form the head was identical and had just 4 muscle blocks. \n\nThese things lived by swimming around in the water filtering plankton from the water through a hole in their front end. That hole wasn’t a mouth, it was just a hole lined with beating hairs that drew in water.\n\nWith such a simple body plan these creatures didn’t require much nervous control by the ‘brain’ to the body.  Each body segment was controlled by a simple reflex arc from those 4 muscle blocks to the spinal cord. The brain could make them more or less responsive to stimulation and so cause the animal to turn left or right, but direct control from the brain to the body was extremely limited and there were correspondingly few nerves running from the brain to the body.\n\nWhat I haven’t mentioned is that this creature had EYES, and therein lies the reason for the crossing over. The early chordate brain was excessively devoted to operating some rather complex eyes that allowed it to see both  food and predators. So why are the eyes so important? Because when light enters they eyes it… crosses over. It inverts. You can follow the link below to get a better idea of this, with diagrams. But for now simply remember that the eye has a lense, and a lense inverts an image left to right as well as up and down. So with a brain devoted to processing inverted images collected through a lense it makes sense for the left brain to control the right body.  After all the information that comes from the left eye will in large part be telling the brain about conditions on the right side of the body.\n\n And so that is exactly what happened. These earliest chordates had (and still have) a brain with massive visual centres and limited  control of the body itself but, and this is vital, the left visual centres are largely located in the right brain. To move towards food on the left side of the body for example the signal form the left eye is processed by the right brain, and the right brain then sends the appropriate signals to the left body. To move towards visually acquired stimuli the signal has to cross over from the side of the brain that processed the data to the OPPOSITE side of the body.\n\nAs chordates became larger and more complex one of the things they did was to grow paired fins. They ceased being wormlike and became fishlike. But paired limbs require far more fine and centralised control than can be provided by a reflex arc to the spinal cord. So the brain assumed control. \n\nThe same brain that had evolved a complex crossover so that visual data corresponded to the correct side of the body was now being asked to assume direct control of paired limbs. Of course evolution works with what it has, not with what is best. The brain had a complex crossover for controlling the muscles of the body, and it couldn’t re-wire that, so it simply built on it. Limb control also crossed over form the left to the right brain even though it was no longer under visual control.\n\nAnd as we became more and more complex we simply kept the same convoluted design. The reason the left brain control the right arm today is simply because hundreds of years ago information form the left eye was processed by the right brain, which was a very sensible solution at the time.
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Use the Linnaeus System:\n\nKingdom Phylum Class Order Family Genus Species\n\nA way to remember it: Katie Put Clams On Fred's Giant Stomach. I learned it in HS Biology 30+ years ago and never have forgotten it.
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What a cool project!  So to answer one of your questions, the crucial distinction among your phyla will be whether or not they're chordates -- which of course includes the vertebrates (but also some invertebrates such as sea squirts and certain worms).  \n\nSo your bipedal wolf (I'm assuming the missing d was a typo, but if "bipeal" is a word from your universe, please let me know) would be phylum chordata, class vertebrata, order mammalia, family canidae, genus canus, species lupus bipedalis (and I'm envisioning something like a cross between Lawrence Talbot and Speaker-to-Animals, without retractible claws).  But that's just off the top of my head.\n\nOne thing I've discussed with my ten-year-old son is the absence of hexapod vertebrates -- e.g. flying horses, winged dragons, etc.  If you were closer, I'd invite you over for coffee and an all-day discussion of where to classify them, and how they evolved.  Since all terrestrial vertebrates have essentially the same structure, it's clear they all shared a common ancestor which makes hexapodal vertebrates, sadly, impossible in our known universe -- so was there a hexapodal (imaginary) marine vertebrate who also scuttled across the floors of silent seas before crawling out of the surf and saying "Hey, the carcharodons can't get me here!  Kewl!"?  ...Which of course suggests all sorts of hexapodal marine vertebrates that shared the same skeletal architecture.  Ooooh, fun.\n\nAnd the final question... so zoology is the study of animals.  There's also cryptozoology, which I've described flippantly as "the study of imaginary animals."  But of course, it's more technically the study of animals that may or may not exist.  So what would we call your zoology, which is the study of animals you've intentionally invented?  Oh, of course, poeiazoology (-poeia, meaing to construct -- as in mythopoeia, the term Tolkien invented to describe the invention of mythologies.)\n\nAnd on that note, elen sila lumen omentielvo!
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Your question has a number of difficult aspects to it, but I have asked a friend of mine to help me do some research into the answer for you and I think he has included a great number of pieces of information that you may find interesting.\nHere is what I eventually decided was the most productive answer to give you. I hope it helps you out! (after all, it is 99% his answer I have included below. He generally gives me such good feedback that I try to quote him directly as much as possible.)\nHere we go: An animal is:\nAn organized living being endowed with sensation and the power of voluntary motion, and also characterized by taking its food into an internal cavity or stomach for digestion; by giving carbonic acid to the air and taking oxygen in the process of respiration; and by increasing in motive power or active aggressive force with progress to maturity.\nOR:\nAny of a kingdom (Animalia) of living things including many-celled organisms and often many of the single-celled ones (as protozoans) that typically differ from plants in having cells without cellulose walls, in lacking chlorophyll and the capacity for photosynthesis, in requiring more complex food materials (as proteins), in being organized to a greater degree of complexity, and in having the capacity for spontaneous movement and rapid motor responses to stimulation" These are the animal subkingdoms, and the principal classes under them:\n* Vertebrata, including Mammalia or Mammals, Aves or Birds, Reptilia, Amphibia, Pisces or Fishes, Marsipobranchiata (Craniota); and Leptocardia (Acrania).\n* Tunicata, including the Thaliacea, and Ascidioidea or Ascidians.\n* Articulata or Annulosa, including Insecta, Myriapoda, Malacapoda, Arachnida, Pycnogonida, Merostomata, Crustacea (Arthropoda); and Annelida, Gehyrea (Anarthropoda).\n* Helminthes or Vermes, including Rotifera, Ch�tognatha, Nematoidea, Acanthocephala, Nemertina, Turbellaria, Trematoda, Cestoidea, Mesozea.\n* Molluscoidea, including Brachiopoda and Bryozoa.\n* Mollusca, including Cephalopoda, Gastropoda, Pteropoda, Scaphopoda, Lamellibranchiata or Acephala.\n* Echinodermata, including Holothurioidea, Echinoidea, Asterioidea, Ophiuroidea, and Crinoidea.\n* Coelenterata, including Anthozoa or Polyps, Ctenophora, and Hydrozoa or Acalephs.\n* Spongiozoa or Porifera, including the sponges.\n* Protozoa, including Infusoria and Rhizopoda.
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Much of the support for the idea that snakes evolved at sea is their close phylogenetic relationship with the extinct group of marine reptiles, the mosasaurs.\n\nBoth snakes and mosasaurs share a number of unique characters, such as a hinge in the middle of the lower jaw, loss of the symphysis joining the two halves of the lower jaw, and the stabilization of the spinal column (the zygosphene-zygantra articulation).  These adaptations seem to have been a major evolutionary success, and led to adaptive radiations of the mosasaurs, snakes and the aigialosaurs (another extinct related group).\n\nIf the group (often called the Pythonomorpha) evolved at sea, it would explain a lot of the other adaptations (such as reduced or modified limbs) that these groups show.  However, more and more the fossil evidence seems to indicate that the Pythonomorpha probably evolved on land, and then each group developed adaptations ideal for marine environments totally separately.\n\nThis solution is not as elegant as it would be if all of the adaptations in the Pythonomorpha occurred at the same time, but it appears that sometimes evolution does not occur as elegantly as we might like.\n\nA terrestrial origin for snakes does explain some of the other unusual features of snakes, such as their eyes which show signs of having been reduced or completely lost at one point, and then an entirely new visual anatomy developed as they re-emerged from a subterrainean existence.
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Pre-Cambrian life was mostly soft-bodied -- there were very few if any creatures with bones, skeletons, or hard shells, so there were very few fossils left.\n\nBesides, it was a long, long time ago -- and geological activity on the earth (volcanic action, subduction of continental plates, erosion, etc.) have wiped out a lof of what was the surface of the earth then. :)
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Evolution of reproduction. Nature finds its way.
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I wouldn't say that I'm anymore intelligent than someone else, but I did want to answer your question, so....\n\nYou are confusing the theory of evolution (diversification of species) with the theory of abiogenesis (life from natural compounds).  That's okay, many people confuse the two.\n\n1.  How did life get from soup to single-celled organisms?  From wikipedia, "J.B.S Haldane suggested that the earth's pre-biotic oceans - very different from their modern counterparts - would have formed a "hot dilute soup" in which organic compounds, the building blocks of life, could have formed.\nIn 1953, taking their cue from Oparin and Haldane, the chemists Stanley L. Miller and Harold C. Urey carried out an experiment on the "primeval soup". Within two weeks organic amino acids, the basic building blocks of life, had formed. While Miller and Urey did not actually create life; they demonstrated that a more complex molecule — the amino-acids — could emerge spontaneously from simpler chemicals, in the presence of an external energy source in an atmosphere largely devoid of oxygen (the experiment involved shooting a spark, representing lightning, into their flask of supposedly primitive earth-gases)."\n\n2.  How did the original cell eat and develop asexual reproduction?   You are putting the cart before the horse.  In order to get to the cell stage, self-replicating molecules had to exist first... i.e. reproduction & "nourishment"  was occurring well before the cell stage.  Also, what are you referring to with "nourishment"?  For a self-replicating molecule, nourishment would consist of other molecules that it could combine with to form more of itself.\n\n3.  In the "soup", how did primordial cells develop resistences?  Resistence to what?  I don't understand this question.  To the environment?  To viruses or bacteria?  You need to elaborate here, I'm sorry.  I think it ties into your next answer, but not sure.  Please read my answer to #4.\n\n4.  How did it evolve everything it needed if it wasn't in it's DNA?  Can you give an example?  Hmm.  I'm trying to understand how you are approaching this question.  Let's say you have 100 little cells, each a little different.  5 cells can withstand a higher water temperature than the others because of a mutation they have.  One day the temperature goes up and kills off the other 95 cells.  That only leaves the 5 with the mutation.  They scamper off and reproduce like crazy... the cell strain has just evolved a little.  Now repeat this a gazillion times with a dynamic interacting environment and there you go.
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Well, on this Earth, primates are the ancestors of the only known sentient species.  I don't know that these means that humans are the 'best' species, even if we are (arguably) the most intelligent.\n\nIf the human evolutionary path is any indication, there may be some prerequisites for the development of sentience.  A large brain is the most obvious one, but things such as free and mobile appendages suitable for tool use may also be required.  As far as bats go, they are limited in the size that their brains can grow to and still be able to maintain flight.  Their forelimbs are also not readily available for manipulatory organs.  \n\nSo a sentient bat species would probably be unlikely.  The ecological niche of intelligent species would probably go to a different species that already displays some of these adaptations to some extent.\n\nMice are a remote possibility for potential sophonts.  They can achieve a semi-bipedal stance and use their forepaws for some remarkable manipulations.  Their current small size is their chief impediment.  Increasing body and brain size to an extent to make them candidates for sentience would also slow them down, remove their stealthiness and ability to fit into tight spaces, and many of the other adaptations that allow them to survive in a world full of predators.\n\nOther than the great apes, I think one of the major candidates for potential for sentience is the racoons.  They are already pretty smart, near the top of the food chain, versatile, adaptable, omnivorous, and curious, and have very well developed forepaws with perhaps the highest level of manual dexterity of any mammal outside the primates.  \n\nI seem to recall a novel by Stephen R. Boyett called 'The Architect of Sleep' in which a man goes to a parallel universe where racoons evolved sentience instead of the primates.  It seemed to be an aquel (a book that fails to spawn the expected series of sequels), but if I remember correctly it was quite intriguing.\n\nAnother intriguing species with curiosity, adaptability, intelligence and manipulative abilities that I think would make an interesting candidate for the development of sentience are some of the large cephalopods (like the giant Pacific octopus, Humboldt's squid or even the giant squid!!)  - imagine the society they might create.
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Snakes lost their legs on land, not in the sea as previous scientists thought, according to new research by professor of biology S. Blair Hedges and postdoctoral fellow Nicolas Vidal.\n\n"Everyone agrees that snakes evolved from lizards and are close relatives to lizards," Hedges said. "What is controversial is the specific group, whether on the land or in the sea."\n\nScientists estimate that snakes evolved 150 million years ago, Vidal said. For many years, they believed in the terrestrial or land theory, which says that snakes evolved from lizards that burrowed underground.\n\nThen, seven years ago, the discovery of a fossilized marine snake with tiny hind legs fueled the marine hypothesis that snakes lost their legs in the sea. The marine snakes called mosasaurs are now extinct, but their closest cousins, the monitor lizards such as the Komodo Dragon, are still alive today.\n\nHedges and Vidal chose two genes and compared them in lizards and snakes to see how closely they are related. From statistical analysis of these gene sequences, they created a family tree.\n\n"These two genes have accumulated different mutations in the different species," Vidal said. "These differences between the species are used to build the evolutionary trees. Snakes are not closely related to the monitor lizards, which means that they cannot have marine origins."\n\nHedges and Vidal's research is significant because of the comprehensive scope of the snakes and lizards studied. They collected DNA from 64 species representing all 19 families of living lizards and 17 of the 25 families of living snakes, Vidal said.\n\n"We mostly acquired DNA from the soft tissues, blood, shed skin, scales and tips of the tails of the animals," he said. "A very small amount is needed, so we can get the sample without killing the animal."\n\nHedges and Vidal acquired samples from other colleagues, their own collections, fieldwork in South America and pet stores that trade exotic animals, Hedges said.\n\nSome of the samples were difficult to acquire because some snakes and lizards are limited to certain parts of the world, such as remote islands, but it was crucial to their study.\n\n"We felt it was important to analyze genes from all the lizard groups, because almost every lizard family has been suggested as being the one most closely related to snakes," Hedges said. "If we had failed to include genes from even one of the lizard families, we could have missed getting the right answer."\n\nA possible theory to explain why snakes dropped their legs on land is that limbs are not conducive to their burrowing habits, Vidal said.\n\n"The idea is that if you have limbs sticking out, it's difficult to get into small openings," Hedges said. "It's more advantageous, because it enables snakes to get more food and offers safety from predators."\n\nHedges and Vidal did not find the closest lizard relative to snakes, but they did succeed in eliminating the monitor and marine lizards as possibilities.\n\n"This study doesn't answer all the questions," Hedges said. "In most fields, questions aren't answered all at once. They're answered in increments, and in this study, we've ruled out the marine theory, but that still leaves a lot of possibilities."\n\nHedges and Vidal said they hope to find the closest relative to snakes in the next year.\n\n"The work by Dr. Hedges and Dr. Vidal is a tremendous contribution to the body of knowledge," said Bryan Fry, deputy director of the Australian Venom Research Unit at the University of Melbourne in Australia. "Their data provides strong evidence for the terrestrial loss of limbs."