when did flatworms and roundworms first appear on the planet?
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Flatworms (Platyhelminthes) and roundworms (Nematodes) are soft-bodied animals, and therefore they're practically absent from the fossil record, because it takes extraordinary circumstances to produce fossils of these type of organisms. \nA fossilized turbellarian found included in Baltic amber, is 40 million years old (see first reference). \nFossil nematodes are also occasionally found in amber from the Cenozoic, but there are possible possible fossils from the Middle Paleozoic (see second link).\nBut anyway, all the major animal phyla are estimated to have been present after the Cambrian explosion (570 million to 495 million years ago) (see third link).
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Cricket by a long way. In it's modern form it can be dated back at least until the 1660's, but probably until the 13th century. There is now evidence to suggest a similar game was even played in ancient Rome!\nAs for baseball, the earliest known mention of the sport is in a 1744 British publication, A Little Pretty Pocket-Book, by John Newbery. It contains a wood-cut illustration of boys playing "base-ball". Rounders was actually only codified in the 1840's, so it is hard to say if baseball came from Rounders or not.
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Look up 'nematodes'.\nLook here too:
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The Aschelminthes (sometimes Aeschelminthes), are closely related to the platyhelminthes and are an obsolete phylum of pseudocoelomate and other similar animals, including as classes the Nematoda, Rotifera, Gastrotricha, Kinorhyncha, and Nematomorpha, and sometimes the Priapulida and Entoprocta. Many of these groups are no longer considered closely related and have been promoted to phyla in their own right. The name is now generally only used as an informal term.\n\nThe phylum Platyhelminthes represents all flatworms in the kingdom Animalia. Flatworms are relatively primitive animals that represent an early lineage in the kingdom. Unlike the even more primitive phylum cnidaria, all flatworms of the phylum Platyhelminthes are bilaterally symmetrical, having an anterior, posterior, dorsal, and ventral end and two seemingly identical lateral surfaces. However, flatworms are the only type of bilaterally symmetrical animal that lacks any type of body cavity, a fluid filled space between the digestive tract and the body wall. In the flatworms, this area is filled with tissue. Flatworms have primitive brains, comprised of clusters of nervous tissue. Two long nerve cords run the length of the body, and they branch to form small nerves running throughout the body. Another hallmark of flatworms is a lack of a complete digestive tract. Flatworms take in food and excrete waste from one single hole. The opening in the gastrula never fully evolves in flatworms to make a tract that travels from one hole in the anterior end to another hole in the posterior end, which would make the tract complete. There are four classes that make up the phylum Platyhelminthes, each with unique structures and living styles.
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Flatworms and roundworms are as different as frogs and snakes. Or perhaps less different when we forget the science part of it.Flat worms hape a flat body, like tape.And they do not have a coelom. What is a coelom? If you cut open a higher animal (eg. a mouse)you will find that their body is like a hollow bag filled with liquids and organs. The empty space of the body in which these organs lie and which is filled up of body fluids is called coelom. In flat worms, this entire space is filled with compact tissue.Sexes are not separate and specialised cells called flame cells are responsible for excretion. In round worms, the coelom exists but is actually pseudocoelom or "false coelom". This means patches of tissue are present scattered in the coelom. Sexes are separate ie. males and females are separate. Moreover an excretory tube is responsible for excretion instead of flame cells.
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In china in the early ages where they used to stuff the skin of deers and some other animals with tiny rocks and form a sphere then kick it around into small holes. It was then transfered to the british who then made it world wide and spread it all around the world..\n\nSure of it and i can bet on my life..
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The earliest living organisms were single-celled. They were prokaryotes, probably bacteria or archaea. They lived 3.8 billion years ago in the Eoarchean Era, a subdivision of the Archean Era.
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Earthworms are hermaphrodites.  Other types of worms look different; females tending to be larger than males, for one thing.
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I can't find anything on that - looks like you are going to have to do an experiment.  You can find earthworms at any bait store, colored light bulbs at the nearest Wal Mart.  have fun!
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Carl Wilhelm Scheele discovered it in 1772, and Joseph Priestly found it in 1774 (independently).  Scheele was a Swede, Priestly was an Englishman.
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Brachiopod Lingula. Having existed nearly unchanged for over 500 million years, and the horseshoe crab (limulus) has been on the planet for several hundred million years, too. Since the average "lifespan" of a species is only a few million years.\n\nQuote (answers.com):\n"The inarticulate brachiopod genus Lingula has the distinction of being the oldest, relatively evolutionarily unchanged animal known. The oldest Lingula occur in the very early Cambrian, roughly 550 million years ago. The origin of brachiopods is unknown. A possible ancestor is a sort of ancient "armored slug" known as Halkeria that was recently been found to have had small brachiopod-like shields on its head and tail."
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A worm is an elongated soft-bodied invertebrate animal. The best-known is the earthworm, a member of phylum Annelida, but there are hundreds of thousands of different species that live in a wide variety of habitats other than soil.\n\nOriginally, the word referred to any creeping or a crawling animal of any kind or size, such as a serpent, caterpillar, snail, or the like (this old usage is preserved in the name "slowworm", actually a lizard). Later this definition was narrowed to the modern definition which still includes several different animal groups. Major phyla include:\n\nAcanthocephala (spiny-headed worms) \nAnnelida (segmented worms) \nChaetognatha (arrow worms) \nGnathostomulida (jaw worms) \nNematoda (roundworms) \nNematomorpha (horsehair worms) \nNemertea (ribbonworms) \nOnychophora (velvet worms) \nPlatyhelminthes (flatworms) \nSipuncula (peanut worms) \nOther invertebrate groups may be called worms, especially colloquially. Many insect larvae are called worms, such as the railroad worm, woodworm, glowworm, or bloodworms.\n\nWorms may also be called helminths, especially in medical or terminology when referring to parasitic worms, especially the Nematoda (roundworms) and Cestoda (tapeworms). Hence helminthology is the study of parasitic worms.\n\nWhen an animal, such as a dog, is said to have worms, it means that the dog is infested with parasitic worms, typically roundworm or tapeworm.\n\nWorm species differ in their abilities to move about on their own. Many species have bodies with no major muscles, and cannot move on their own. They must be moved by forces or other animals in their environment. Many species have bodies with major muscles, that let them move on their own. They are a type of muscular hydrostat.
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Reproduction is usually sexual. Males are usually smaller than females (often very much smaller) and often have a characteristically bent tail for holding the female for copulation. During copulation, one or more chitinized spicules move out of the cloaca and are inserted into genital pore of the female. Amoeboid sperm crawl along the spicule into the female worm.\n\nEggs may be embryonated or unembryonated when passed by the female, meaning that their fertilized eggs may not yet be developed. In free-living roundworms, the eggs hatch into larva, which eventually grow into adults; in parasitic roundworms, the life cycle is often much more complicated.
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Belief in a flat Earth is found in humankind's oldest writings. In early Mesopotamian thought the world was portrayed as a flat disk floating in the ocean, and this forms the premise for early Greek maps like those of Anaximander and Hecataeus. This theory was clearly rejected after colombus's expedition.
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Tube worms can live 200+ years
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A long time ago in human history, people thought that Earth was flat, and at the universe's center. They believed that seven members of the solar system forever circled around us—see graphic to the right, or view one from Censorinus - Sur le jour natal. \n\n     Some Mediterranian peoples also believed that each hour of the day was ruled by either the Sun, Moon or one of five then-known planets, all of which were thought of as gods. The sequence in which they thought hours were governed was the inverse order of distance they believed those solar system objects to be from Earth. \n\nDuring this time, Egyptians thought that the most distant was Saturn, shown at the bottom of the graphic above. They thought that the order of closer members (shown counterclockwise following Saturn) was Jupiter, Mars, Sun, Venus, Mercury and closest, the Moon. So they believed that the first hour was ruled by Saturn, the second by Jupiter and so on. \n     Egyptians also believed that after each seven hours the order in which these objects ruled was repeated, so it started again with Saturn. \n     According to those ancient Egyptians, the planet that ruled the first hour also governed the entire twenty-four hour period, and gave its name to that day.    The first (and also the 8th, 15th and 22nd) hours of the first day were sacred to Saturn, the 23rd to Jupiter, the 24th to Mars and the first hour of the next day to the Sun. Therefore, they believed that the first day was ruled by and named after Saturn (Saturday) and the second was ruled by (and named after) the Sun (Sunday). \n\nEgyptians once divided all twelve 30-day months (of their 360-day calendar year) into three 10-day weeks in the same manner as Greeks of the same period.    The epoch at which planet worship caused them to change its length to seven days is not known, but it must have been over twenty-five hundred years ago because Herodotus, writing in his History during the 5th century B.C. said: "Here are some other discoveries of the Egyptians. They find...each day belongs to a god..." \n     Adherents of the cult of Sin at Harran, who were known as Harranians or Sabeans by Arabic and Syrian authors, named their days after the same solar system members  as Egyptians and Persians. Like Hebrews and many other peoples, they considered the one named after Saturn to be the seventh day, so they began their week with a day named after the Sun. All seven days were named after solar system members in the same order as they were in Egypt. \n\nIt is interesting to note that these exact same solar system objects, and in the same sequence, were also used to name days in ancient India, Tibet and Burma.   This is also true of names for Japanese days of the week, but the custom there has been traced back only a thousand years.  \n     Roman soldiers stationed in Egypt became accustomed to the pagan seven-day week and began to introduce it into their own homeland to replace their eight-day marketing week. Octavian (Caesar Augustus) and succeeding Roman rulers permitted this practice but it wasn't made official until the emperor Constantine took that step in A.D. 321. \n     English names for days of the week are derived from Anglo-Saxon names for those same seven heavenly bodies that were revered by ancient peoples. Compare those English and Anglo-Saxon day names in the table below. Other similarities between day and "planet" names in various countries can be observed there.
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Well it really depends on your definition of animal,\n\nAnts would be a pretty good answer,\nbut if you are looking at all animals, then certain people believe that there are more species of nematodes (round worms) than any other group.