quora
Nobody downloaded yet

A Silurian placoderm with osteichthyan - Research Paper Example

Comments (0) Cite this document
Summary
A Silurian placoderm with osteichthyan Summary of Article The ancient fossil register of jawed vertebrates (gnathostomes) is typified by four defined groups, which include the Osteichthyes, Placoderm, Acanthodii and Chondrichthyes…
Download full paperFile format: .doc, available for editing
GRAB THE BEST PAPER92.9% of users find it useful
A Silurian placoderm with osteichthyan
Read TextPreview

Extract of sample
"A Silurian placoderm with osteichthyan"

Download file to see previous pages In this regard, the Chondrichthyes are deficient of the huge cutaneous bones that typify the Osteichthyes. The Chondrichthyes are regarded as the cartilaginous fish while the Osteichthyes are regarded as the bony fish. The mutual opposition of these distinctions and the body structure of the last common ancestor of gnathostomes have continued to be a topic of consensus among scientists (Zhu et al, 2013). In this paper, Zhu and colleagues (2013) identify and delineate a three-multidimensional well-maintained placoderm fish from Silurian of China with combined features of a placoderm-like cutaneous skull roof, shoulder girdle and braincase with osteichthyan-like cutaneous bones of the mandibular and hyoid arches, and a palatoquadrate sharing obtained attributes with crown gnathostomes. This is a thing that had not been seen before. The phylogenetic analysis revealed that the skull roof is level and sturdily curved horizontally. Most of the braincase of the fish was covered with rounded, central and nape plates, winged by corresponding postorbital, peripheral and frontal and subsequent paranuchal plates along the route of the arterial intraorbital and primary lateral line grooves. Additionally, the petite and thin proboscis constitutes a snout, a premedian and premaxillary those seem to be attached mesially. The Dermal cheek comprised the jugal, maxilla and a quadrajugal with a sensory channel pattern. The trunk armour comprised of attributes similar to those of the early arthrodires such as phlyctaeniid. On the other hand, the analysis revealed that the braincase was wide and flattened, replicating that of the ancient arthrodires (Zhu et al, 2013). This review was executed to identify the phylogenetic position of Entelognathus and the effect of its typescripts on gnathostome organic evolution. The evaluation was carried out using a modified version of the data. Entelognathus was placed with arthrodires, crown gnathostomes and ptyctodonts by the severe accord of 117 most frugal trees. The results of the analysis put several acanthodians under the gnathostome and osteichthyan stem clusters. The phonetic resemblances between the chondrichthyans and acanthodians were translated as symplesiomorphies. Zhu et al’s (2003) results portrayed that the resemblances represent synapomorphies of the chondrichthyan entire cluster. The classification of all acanthodians in the chondrichthyan stem cluster indicates that macronery in the preceding mutual ancestor of crown gnathostomes. The results of the analysis also indicated that Chondrichthyes and Osteichthyes had macromeric cutaneous bones and offered a new theoretical account for reviewing crown gnathostome variance. Personal Response This paper clearly brings out a comparison of the four groups of the jawed vertebrate. It makes it clear to me, as a reader, by indicating that two of the groups are still in existent while two are extinct. Additionally, from my observation, similarities and differences between the groups are well articulated through diagrams through the article. The article explains each of the body structures and skeletons before comparing them. For instance, the article shows that Osteichthyans and Placoderms have macromeric cutaneous skeletons dominated by a huge body plates while Chondrichthyans and Acanthodians have micromeric cutaneous skeletons that primarily consist of scales. The article has brought me at ...Download file to see next pagesRead More
Cite this document
  • APA
  • MLA
  • CHICAGO
(“A Silurian placoderm with osteichthyan Research Paper”, n.d.)
A Silurian placoderm with osteichthyan Research Paper. Retrieved from https://studentshare.org/biology/1487116-a-silurian-placoderm-with-osteichthyan
(A Silurian Placoderm With Osteichthyan Research Paper)
A Silurian Placoderm With Osteichthyan Research Paper. https://studentshare.org/biology/1487116-a-silurian-placoderm-with-osteichthyan.
“A Silurian Placoderm With Osteichthyan Research Paper”, n.d. https://studentshare.org/biology/1487116-a-silurian-placoderm-with-osteichthyan.
  • Cited: 0 times
Comments (0)
Click to create a comment or rate a document
CHECK THESE SAMPLES - THEY ALSO FIT YOUR TOPIC
Dunkleosteus
The genus Dunkleosteus is in the order Arthrodita and family of Dinichthyidae. The Gnathostomata became the dominant organisms during the Devonian Period. Their primary difference to other vertebrates is their vertical biting device or the jaws which "consist of an endoskeletal mandibular arch and a wide variety of exoskeletal grasping, crushing, or shearing organs" including the teeth and the jaw bones (Janvier 2).
2 Pages(500 words)Essay
Geology of Brazil Essay
With rapid urban growth in the country, by 2005 over 80 percent of the total population was living in urban areas. “This growth aids economic development but also creates serious social security, environmental, and political problems for major cities” (BWHA 2011).
5 Pages(1250 words)Essay
Diversity Of Phylum Chordata
All known vertebrates are broadly grouped in the phylum Chordata. This grouping takes into consideration a number of factors known as diagnostic factors. Therefore for an animal to be considered a chordate it must have or it had the following diagnostic features: Notochord: a long flexible rod of cartilage that runs along the body Pharyngeal gill slits: Are the holes or perforations along the neck or throat.
10 Pages(2500 words)Essay
Ordovician Life in Ohio
One of the most notable elements in the state of Ohio is sea life fossils that existed during the Ordovician period. As is well recognized during this geologic period Ohio was at the bottom of the ocean and its present-day geological elements represent fossilized remains of this seafloor period.
9 Pages(2250 words)Research Paper
Indiana Geology and Landscapes

The author explains that there are hills and areas of higher land, but this is simply because these parts of the sedimentary rocks,  which include limestone, dolomite, shale, sandstone, and siltstone, although they tip to the south-west, were always higher in elevation than the intrusive ice sheets. 

3 Pages(750 words)Assignment
The Historical Formation of West Virginia
During the Devonian Period, which according to Wiktionary (2008) is "the geologic period (which can be divided into a lower, a middle and an upper period) from about 415 to 360 million years ago", important geologic features of eastern West Virginia were being formed.
3 Pages(750 words)Essay
Arizona's Petrified Forest/ Painted Desert: Rock types, Fossils, Stream Systems, Weathering, Geologic Structures, Geological Time
Its fascinating Plant and Animal life proves to be a fascinating science that is continuously explored by all science lovers. It is known to be the world’s largest
6 Pages(1500 words)Essay
Paleozoic Fossils
Plants were the first sign of life in this era. 5. Permian Period was the last time period in the Paleozoic Age. The time is about 290 million years ago from now. The formation of Pangea became complete by this age. The reptiles got a new life because of the climatic change.
3 Pages(750 words)Essay
Ordovician Mass Destinction
It was around the end of this time period that the event is supposed to have taken place which is about 440-450 million years ago. In order to see what organisms and species had been affected by this mass
8 Pages(2000 words)Essay
Does Dr Who tell us about science and technology or the Britain of its time Discuss
The development in this era brought significant changes in the British society. In addition, numbers of political and social events took place during the period. The development introduced several inventions; among them was the ‘digital computer game’ (Space war), audiocassette and touch-tone telephones.
12 Pages(3000 words)Essay
sponsored ads
We use cookies to create the best experience for you. Keep on browsing if you are OK with that, or find out how to manage cookies.
Let us find you another Research Paper on topic A Silurian placoderm with osteichthyan for FREE!
logo footer
Contact us:
+16312120006
Contact Us Now
FREE Mobile Apps:
  • StudentShare App Store
  • StudentShare Google play
  • About StudentShare
  • Testimonials
  • FAQ
  • Blog
  • Free Essays
  • New Essays
  • Essays
  • Miscellaneous
  • The Newest Essay Topics
  • Index samples by all dates
Join us:
Contact Us