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| | CarlZimmer.com |
 | | One of the parts of the vertebrate brain that's missing from the lancelet nerve cord is the most forward portion of the forebrain, known as the telencephalon, which among other tasks handles signals from the nose. | | | He suggests that the common ancestor of vertebrates and lancelets used its protolimbic system to switch between its handful of behaviors, such as swimming and feeding. | | | Lancelets, for example, apparently have no sense of smell. |
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http://www.carlzimmer.com/articles/2000/articles_2000_6.html
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| | American Zoologist: Lancelets: A New Look at Some Old Beasts, The |
| | One could question, however, whether there is sufficient evidence to adopt terms such as "tectum" and "balance organ" for the lancelet brain. | | | The contribution of Poss and Boschung represents a much needed clarification of the complicated taxonomy, systematics and biogeography of lancelets. | | | The lancelet renal system is intermediate between a proto- and a metanephridial system, and it can be understood in terms of vertebrate nephron structure (Ruppert). |
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http://www.findarticles.com/p/articles/mi_qa3746/is_199709/ai_n8779961
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| | Lancelet - Wikipedia, the free encyclopedia |
| | The lancelet notochord, unlike the vertebrate spine, extends into the head. | | | The lancelets (subphylum Cephalochordata, and traditionally known as the amphioxus) are a group of primitive chordates. | | | They are an important object of study in zoology as they provide indications about the origins of the vertebrates. |
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http://en.wikipedia.org/wiki/Cephalochordata
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| | [No title] |
| | The vertebrate brain apparently is an elaboration of an ancestral structure similar to the lancelet’s simple nerve cord tip. | | | Unlike the pharyngeal slits of lancelets, which are used primarily for suspension feeding, gill slits are associated with muscles and nerves that allow water to be pumped through the slits. | | | In lancelets, the pharynx and gill slits are feeding structures and play only a minor role in respiration, which primarily occurs across the external body surface. |
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http://www.nicerweb.com/class/bio1151/Locked/media/doc/34_LectureOutline_LO.doc
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| | part34 |
| | By contracting units on opposite sides of the body alternately against the flexible but incompressible notochord, lancelets flex their bodies during swimming much the way fishes do. | | | Lancelets have many characteristics that link them to tunicate "tadpoles", but they have also evolved a few more advanced traits that link them to higher vertebrates. | | | Like most higher chordates, lancelets have segmental muscles organized into chevron-shaped units on either side of the notochord, a distinct advance over the muscular organization of tunicates. |
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http://goldenplains.sk.ca/courses/science/Bio20/Unit4/part34.htm
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| | Fossil Fortune Cookie |
| | This is generally seen as a chordate, similar in some ways to the lancelets. | | | The researchers think that Cathaymyrus, like Pikaia, is a fossil relative of modern lancelets. | | | Vertebrates have generally lost the full filter-feeding system, though intriguing traces remain, For example, in sea-squirts and lancelets, an organ called the endostyle secretes mucus that is used to trap food particles. |
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http://www-geology.ucdavis.edu/~cowen/HistoryofLife/Cathaymyrus.html
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| | American Scientist Online - The Lancelet |
| | As unflattering as this may sound to a vertebrate wearing an Armani jacket, our authors provide further support for this theory on the basis of recent studies on the lancelet's molecular biology and embryonic development. | | | Resembling a little, colorless anchovy fillet, the lancelet is believed to bear an uncanny likeness to the invertebrate ancestor of the vertebrates. | | | Generations of zoology students have studied the lancelet—also known as amphioxus—because of the clues it may hold about the evolutionary history of the vertebrates. |
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http://www.americanscientist.org/template/AssetDetail/assetid/15499
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| | The Biological Bulletin: Ciliary hovering in larval lancelets (=Amphioxus).@ HighBeam Research |
| | By using improved methods (6, 7) to culture and observe healthy pre-metamorphic larvae in relatively deep containers, we demonstrated a prominent hovering behavior. | | | Search for more information on HighBeam Research for. | | | Larvae of lancelets (=amphioxus) are of special interest because they figure prominently in debates about vertebrate origins (1), can sometimes grow into a giant "amphioxides" form (2, 3), have a puzzling right-left asymmetry (4), and constitute a major zooplankton resource in parts of the Atlantic (5). |
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http://highbeam.com/doc/1G1:17355708/Ciliary+hovering+in+larval+lancelets+...
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| | Chordates Overview |
| | This is an important distinction because it would change our reconstruction of the common ancestor of all deuterostomes from an echinoderm-like suspension feeder (like a crinoid) to more of a worm-like ancestor (perhaps like a chordate lancelet or hemichordate enteropneust worm). | | | New molecular and morphological evidence would suggest instead that chordates are sister taxon to (hemichordates + echinoderms). | | | The classification above shows the relationship as an unresolved trichotomy (all three are regarded as sister taxa, at the same level of indentation in this unranked classification, without specifying which two of the three are closer relatives). |
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http://biology.fullerton.edu/biol261/rev/chordates.html
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| | Ecology and habitats (from cephalochordate) -- Britannica Student Encyclopedia |
| | More results on "Ecology and habitats (from cephalochordate)" when you join. | | | Lancelets lie buried beneath this substrate, often with their mouths protruding above the surface, allowing them to take in water laden with food. | | | Lancelets are distributed throughout the world along tropical and temperate coasts. |
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http://www.britannica.com/ebi/article-49503
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| | Grzimeks Animal Life Encyclopedia |
| | This characteristic (as well as many others) distinguishes them from some fishlike chordates, such as the lancelets (Amphioxiformes), but, of course, amphibians, reptiles, birds, and mammals also have a cranium. | | | Several unrelated groups of nonfishes (e.g., lancelets, sea snakes, and some amphibians) possess finlike modifications associated with their tails that facilitate locomotion in water. | | | Furthermore, althoughsome fishes, such as hagfishes and lampreys (Petromyzontidae), lack paired fins, the paired appendages of amphibians, reptiles, birds, and mammals are considered homologous to the paired fins of fishes. |
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http://www.wordtrade.com/science/lifescience/grzimeksanimallifeencyclopedi.htm
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| | Section 32-2 Assignment |
| | Tunicates and lancelets are examples of ____________________ chordates. | | | Both tunicates and lancelets are ____________________ feeders in their adult forms. | | | Tunicates keep the nerve cord, notochord, and postanal tail throughout their lives. |
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http://www.southbarber.com/Erikson/2b32-2.htm
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| | Chordata on Encyclopedia.com |
| | The meagerness of the skeleton is considered a degenerate, not a primitive condition. | | | A lancelet has a long body, pointed at both ends, with a large notochord that extends almost from tip to tip and is present throughout life. | | | A third invertebrate group, comprising the acorn worms and their relatives, shows affinities with chordates and has sometimes been considered a chordate subphylum, but is now often classified in a phylum of its own, the Hemichordata. |
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http://www.encyclopedia.com/html/C/Chordata.asp
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| | Biology of chordates video guide shows vertebrate evolution. |
| | The affinities between Cephalochordates and the hagfish/lamprey group are most striking when viewing the larva of the lamprey (ammocoetes larva). | | | The lancelet has a strong supportive notochord, and angled muscles along the body used for brief periods of swimming, such as when the animal is dislodged from the sand. | | | To many students, the phylum Chordata doesn’t seem to make much sense. |
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http://ebiomedia.com/prod/BOchordates.html
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| | M18.htm |
| | Amphioxus (actually Branchiostoma sp.), is an organism that is familiar to most biology students, as it is often used in the laboratory to illustrate some of the basic chordate features. | | | They don't have a true brain, however they possess two pairs of cerebral lobes and nerves. | | | Present day lancelets, such as Branchiostoma sp., bury in sand where they draw in water through their mouth and filter out small organisms for food. |
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http://www.meer.org/M18.htm
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| | Subphylum Cephalachordata |
| | Lancelets also show bilateral symmetry, and are much longer than they are wide. | | | The lancelets, as animals in this subphylum are known, have a mouth in the head end of the body, gill slits in the pharynx region, a dorsal nerve cord contained inside a notochord, and a tail that extends past the anus. | | | They have bladelike structures on the outside of their body and have segmented muscles that can bend, allowing the animal to slowly swim. |
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http://www.sidwell.edu/us/science/vlb5/Labs/Classification_Lab/Eukarya/Animalia/Chordata/Cephalachordata
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| | [No title] |
| | Although the outwardly resemble vertebrates, the feeding mechanism of lancelets is similar to that of Urochordates. | | | Among the invertebrates, the body form of lancelets most resembles vertebrate animals like fishes. | | | What are some key differences between lancelets and vertebrates? |
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http://www.geneseo.edu/~bosch/Ch21-22.doc
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| | Section A - Lancelets (Amphioxus) |
| | Eggs that develop according to a deuterostome pattern and embryos with a posterior blastopore. | | | In addition, lancelet development is more like that of the vertebrates (except for the echinoderms) than the invertebrates | | | Pikaia had segmented muscle blocks (myomeres) like a fish and a notochord but its shape was more that of a lancelet than a fish. |
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http://www.reef.edu.au/asp_pages/seca.asp?formno=20
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| | lancelets - OneLook Dictionary Search |
| | Words similar to lancelets: lancelet, amphioxidae, branchiostomidae, cephalochordata, family amphioxidae, family branchiostomidae, subphylum cephalochordata, more... | | | We found 2 dictionaries with English definitions that include the word lancelets: | | | Tip: Click on the first link on a line below to go directly to a page where "lancelets" is defined. |
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http://www.onelook.com/?w=lancelets
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| | ITIS Standard Report Page: Cephalochordata |
| | Cephalochordata -- amphioxus, amphioxus, amphioxus (common), anfioxo, cefalocordado, lancelets, lancelets | | | The time it takes to return results is dependant on the speed of the individual sites and may take several minutes. | | | Lancelets (Cephalochordata: Branchiostomatidae): How many species are valid? |
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http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=159679
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| | Cephalochordata - Lancelets |
| | muscles in segments; weak (lancelets can swim but do rarely) |
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http://www.jochemnet.de/fiu/BSC1011/BSC1011_16/sld004.htm
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| | AMPHIOXUS - LoveToKnow Article on AMPHIOXUS |
| | Lancelets are found in brackish or salt water, generally near the coast, and have been referred to several genera and many species. | | | They were first discovered by P. Pallas in 1778, who took them to be slugs and described them under the name Limax lanceolatus. | | | To properly cite this AMPHIOXUS article in your work, copy the complete reference below: |
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http://www.1911ency.org/A/AM/AMPHIOXUS.htm
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| | The Lancelets (Subphylum Cephalochotdata) |
| | The body is designed with three openings; a mouth, guarded by tentacles called buccal cirri and through which water enters, an atriopore towards the posterior (tail) end of the animal through which water exits and behind this an anus through which waste products exit. | | | They have long fascinated biologists because they exhibit all four basic characteristics of the phylum Chordata (a dorsal nerve cord, a notochord, a post annul tail and pharyngeal gill slits) in the adult stage of their lives. | | | Among the 28 known species one occurs off European shores (Branchiostoma lanceolatum) which was the original lancelet, and four occur of the coasts of North America, one of which is Branchiostoma virginiae. |
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http://www.earthlife.net/inverts/cephalochordata.html
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| | Introduction to the Cephalochordata |
| | Known as lancelets or as amphioxus (from the Greek for "both [ends] pointed," in reference to their shape), cephalochordates are small, eel-like, unprepossessing animals that spend much of their time buried in sand. | | | With about twenty-five species inhabiting shallow tropical and temperate oceans, the Cephalochordata are a very small branch of the animal kingdom. |
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http://www.ucmp.berkeley.edu/chordata/cephalo.html
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| | Lancelets |
| | Although they can swim fairly well, most animals are found with their tails buried in the sand with only the anterior end protruding. | | | The Subphylum Cephalochordata contains about 30 species of animals called lancelets. | | | Note: This page is best viewed at a screen size of 800 X 600 pixels |
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http://bioweb.uwlax.edu/zoolab/Table_of_Contents/Lab-9a/Lancelets/lancelets.htm
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