The outermost layer of skin, the epidermis, produces a variety of growths in animal and bird species. Because dinosaurs were reptiles, and modern reptiles have scales and armor plates on their skin, it was long assumed that dinosaurs had the same type of skin coverings. However, dinosaurs had many traits that modern reptiles lack, and evidence gathered by paleontologists indicates that dinosaurs may have, in fact, possessed feathers like modern birds.
Descendants
One reason for believing that dinosaurs possessed feathers is that they are a defining trait of their descendants: modern birds. All modern birds have feathers that cover their bodies to some degree, and this is true of all birds in the fossil record as well. Therefore, it is reasonable to assume that they inherited this trait from their ancestors.
Fossil Feathers
There is physical evidence that some dinosaurs did certainly have feathers. Feathers are clearly visible on fossils ranging from the duck-sized Mei Long to the largest known feathered dinosaur, the Yutyrannus huali, a Tyrannosaurus cousin that weighed more than 3,000 pounds.The feathered fossils belong to species that are unrelated and include both predator and prey animals. This strongly suggests that feathers were common to all dinosaurs.
Need for Feathers
While feathers are most commonly associated with flight, they almost certainly evolved first as a way of regulating temperature. Many of the feathers that have left fossil imprints look more like the downy fluff of a modern chick or hatchling than the stiff plumes of adult birds. Such filament-like feathers would likely have been helpful in trapping body heat. Warm-blooded modern birds use feathers to insulate themselves in colder climates and it is reasonable to assume that dinosaurs would have put feathers to the same use.
Many scientists take issue with the arguments you read in the article. They don’t think those arguments prove that all dinosaurs had feathers.
Take the descendants argument. We know that birds evolved from theropod dinosaurs, which is a specific group of mostly predatory dinosaurs. Some theropods were feathered- so feathered that they might have looked more like turkeys than lizards. But not all dinosaurs have modern descendants we can look at. Many of the herbivorous, plant eating dinosaurs have no close living relatives. So, the presence of feathers in all extinct and modern birds indicates that they inherited them from theropods. It doesn’t prove that all dinosaurs had feathers, or even that all theropods had them, but some must have.
Well, what about the fossil specimens of some dinosaurs that had feathers? That also doesn’t necessarily mean that dinosaurs were gigantic chickens or pigeons. There are also fossil specimens of skin impressions from other dinosaur species that show no evidence of any kind of feathers. A number of prominent dinosaur lineages: Stegosaurs, Ankylosaurs,Triceratops, as well as the sauropods, show no record of feathers. The skin samples we can connect to those species show bumpy skin, scales, or armor plates.
Ok, so how about the need for feathers? Feathers do make great insulation, that's true, but larger dinosaur species could have relied on gigantothermy. Gigantothermy means that an animal can be so large that it takes a long time for its internal temperature to change significantly, which contributes to a consistent average temperature despite daily environmental temperature changes. There are animals, such as large sea turtles, which maintain their temperatures this way. Another relevant issue is that if dinosaurs had relied on heat from the sun to maintain their core temperatures, then feathers that block sunlight from reaching the skin would have been unhelpful.
The article and lecture discusses the topic about whether dinosaurs have feathers or not. The author of the reading passage agree with the idea and provide three reasons to support his position. However, the lecturer has an opposing perspective and provide evidences to support his conclusion.
According to author, modern birds have been descendant from dinosaures and as most birds have feathers, the author concludes that this feature have been inherited from dianosaures and hence all the dinosaures have feathers. However, the lecturer suggest there might be a specific group of dinosaurs having feathers, but not all of them. He said that there were many herbivores dinosaures which were not even close to Tyrannosaurus, which were covered with feathers. If the giant animal would be covered woth feathers, it may look like wild turkey or lizard.
Secondly, the author suggest that there were several fossi found to have a presence of feather around their body. It ranged from small to large dinosaures and hence gave the conclusion that it will be common to all the dinosaurs. The lecturer provide evidence that there were fossil found that show clear evidence of not having feather, instead there bodies were covered with scales and armor plates.
Lastly, the author suggest that the presence of the feather will help dinosaurs to maintain their body temperature. It will provide support to protect them during the cold season and hence it act as important trait and therefore present in all the dinosaurs. The lecturer believe in theory of gigantothermy, as the dinosaurs are large animal they will take a very long time to change their internal body temperature, inspite the enviornmental chanegs. If they are not able to capture heat from the sun, the feathers would be unhelpful. Hence, the lecture concludes that it is not necessary that all the dinosaurs skin are covered with feathers.
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- The outermost layer of skin the epidermis produces a variety of growths in animal and bird species Because dinosaurs were reptiles and modern reptiles have scales and armor plates on their skin it was long assumed that dinosaurs had the same type of skin 81
- In 20 years there will be less pollution in the air than there is today 75
- Claim Nations should suspend government funding for the arts when significant numbers of their citizens are hungry or unemployed Reason It is inappropriate and perhaps even cruel to use public resources to fund the arts when people s basic needs are not b 50
- The populations of many fish species are rapidly disappearing due to overfishing and pollution There are many ways to address this issue and one of the most popular is aquaculture also known as fish farming Raising fish in a controlled environment has man 73
Grammar and spelling errors:
Line 7, column 193, Rule ID: IT_VBZ[1]
Message: Did you mean 'acts'?
Suggestion: acts
...hem during the cold season and hence it act as important trait and therefore presen...
^^^
Transition Words or Phrases used:
but, hence, however, if, lastly, look, may, second, secondly, so, therefore
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 16.0 10.4613686534 153% => OK
Auxiliary verbs: 8.0 5.04856512141 158% => OK
Conjunction : 12.0 7.30242825607 164% => OK
Relative clauses : 11.0 12.0772626932 91% => OK
Pronoun: 26.0 22.412803532 116% => OK
Preposition: 32.0 30.3222958057 106% => OK
Nominalization: 5.0 5.01324503311 100% => OK
Performance on vocabulary words:
No of characters: 1600.0 1373.03311258 117% => OK
No of words: 310.0 270.72406181 115% => OK
Chars per words: 5.16129032258 5.08290768461 102% => OK
Fourth root words length: 4.19604776685 4.04702891845 104% => OK
Word Length SD: 2.56486303192 2.5805825403 99% => OK
Unique words: 155.0 145.348785872 107% => OK
Unique words percentage: 0.5 0.540411800872 93% => More unique words wanted or less content wanted.
syllable_count: 499.5 419.366225166 119% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 11.0 8.23620309051 134% => OK
Subordination: 3.0 1.25165562914 240% => Less adverbial clause wanted.
Conjunction: 1.0 1.51434878587 66% => OK
Preposition: 1.0 2.5761589404 39% => More preposition wanted as sentence beginning.
Performance on sentences:
How many sentences: 15.0 13.0662251656 115% => OK
Sentence length: 20.0 21.2450331126 94% => OK
Sentence length SD: 38.8155753389 49.2860985944 79% => OK
Chars per sentence: 106.666666667 110.228320801 97% => OK
Words per sentence: 20.6666666667 21.698381199 95% => OK
Discourse Markers: 5.0 7.06452816374 71% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 1.0 4.19205298013 24% => OK
Sentences with positive sentiment : 6.0 4.33554083885 138% => OK
Sentences with negative sentiment : 0.0 4.45695364238 0% => More negative sentences wanted.
Sentences with neutral sentiment: 9.0 4.27373068433 211% => Less facts, knowledge or examples wanted.
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.187434647524 0.272083759551 69% => OK
Sentence topic coherence: 0.0633623443152 0.0996497079465 64% => OK
Sentence topic coherence SD: 0.0486799392047 0.0662205650399 74% => OK
Paragraph topic coherence: 0.110571187277 0.162205337803 68% => OK
Paragraph topic coherence SD: 0.0436429827861 0.0443174109184 98% => OK
Essay readability:
automated_readability_index: 13.2 13.3589403974 99% => OK
flesch_reading_ease: 51.18 53.8541721854 95% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 11.1 11.0289183223 101% => OK
coleman_liau_index: 12.65 12.2367328918 103% => OK
dale_chall_readability_score: 7.79 8.42419426049 92% => OK
difficult_words: 62.0 63.6247240618 97% => OK
linsear_write_formula: 11.0 10.7273730684 103% => OK
gunning_fog: 10.0 10.498013245 95% => OK
text_standard: 13.0 11.2008830022 116% => OK
What are above readability scores?
---------------------
Rates: 81.6666666667 out of 100
Scores by essay e-grader: 24.5 Out of 30
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Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.