A huge marine mammal known as Steller’s sea cow once lived in the waters around Bering Island off the coast of Siberia. It was described in 1741 by Georg W. Steller, a naturalist who was among the first Europeans to see one. In 1768 the animal became ex

The article and lecture both discuss about the cause of the extinction of Steller’s Sea Cows. The article provides three possible theories about the main cause of extinction of sea cows. The lecturer cast doubts on to these claims and states that there is some other known reason which is not mentioned in the article.

To begin with, the article contends that overhunting of the sea cows by the native Siberian people might be the main reason for their extinction. However, the lecturer argues that It is unlikely that people in the Siberian coasts have overhunted as sea cows are huge animals weighing around tonnes. He further mentions that the population in the Siberian coasts is generally less and one sea cow itself can feed the people in the coasts for several months.

Secondly, The article claims the ecological changes leading to decrease in Kelp which is the food for sea cows might be a possible reason. The lecturer challenges these claims by saying that if ecological changes effected sea fish there should be a drop other fishes also. Further, he mentions that there is evidence from the local fishing that there is decrease in other marine life. So sea cows becoming extinct because of food might not be a correct reason.

Lastly, the author states that the European fur traders might have killed the sea cows, the challenges this by saying that the numbers of sea cows was already low as the eurpoen fur traders reached Siberian coasts and they might not be the reason for sea cows extinctions.

All in all the lecturer points over various weakness in the authors claims and convincingly states that sea cows have not become extinct for any of the reasons mentioned in the article.

Votes
Average: 7.3 (1 vote)
Essay Categories

Grammar and spelling errors:
Line 1, column 193, Rule ID: ENGLISH_WORD_REPEAT_BEGINNING_RULE
Message: Three successive sentences begin with the same word. Reword the sentence or use a thesaurus to find a synonym.
...e main cause of extinction of sea cows. The lecturer cast doubts on to these claims...
^^^
Line 3, column 181, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...tion. However, the lecturer argues that It is unlikely that people in the Siberi...
^^
Line 3, column 293, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...ea cows are huge animals weighing around tonnes. He further mentions that the pop...
^^
Line 5, column 269, Rule ID: ALSO_SENT_END[1]
Message: 'Also' is not used at the end of the sentence. Use 'as well' instead.
Suggestion: as well
...ish there should be a drop other fishes also. Further, he mentions that there is evi...
^^^^

Transition Words or Phrases used:
also, however, if, lastly, second, secondly, so, to begin with

Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments

Performance on Part of Speech:
To be verbs : 14.0 10.4613686534 134% => OK
Auxiliary verbs: 7.0 5.04856512141 139% => OK
Conjunction : 5.0 7.30242825607 68% => OK
Relative clauses : 13.0 12.0772626932 108% => OK
Pronoun: 20.0 22.412803532 89% => OK
Preposition: 30.0 30.3222958057 99% => OK
Nominalization: 5.0 5.01324503311 100% => OK

Performance on vocabulary words:
No of characters: 1427.0 1373.03311258 104% => OK
No of words: 292.0 270.72406181 108% => OK
Chars per words: 4.88698630137 5.08290768461 96% => OK
Fourth root words length: 4.13376432452 4.04702891845 102% => OK
Word Length SD: 2.38868083167 2.5805825403 93% => OK
Unique words: 135.0 145.348785872 93% => More unique words wanted.
Unique words percentage: 0.462328767123 0.540411800872 86% => More unique words wanted or less content wanted.
syllable_count: 425.7 419.366225166 102% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK

A sentence (or a clause, phrase) starts by:
Pronoun: 2.0 3.25607064018 61% => OK
Article: 9.0 8.23620309051 109% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 1.0 2.5761589404 39% => More preposition wanted as sentence beginning.

Performance on sentences:
How many sentences: 12.0 13.0662251656 92% => OK
Sentence length: 24.0 21.2450331126 113% => OK
Sentence length SD: 49.3431155842 49.2860985944 100% => OK
Chars per sentence: 118.916666667 110.228320801 108% => OK
Words per sentence: 24.3333333333 21.698381199 112% => OK
Discourse Markers: 5.16666666667 7.06452816374 73% => OK
Paragraphs: 5.0 4.09492273731 122% => OK
Language errors: 4.0 4.19205298013 95% => OK
Sentences with positive sentiment : 0.0 4.33554083885 0% => More positive sentences wanted.
Sentences with negative sentiment : 5.0 4.45695364238 112% => OK
Sentences with neutral sentiment: 7.0 4.27373068433 164% => OK
What are sentences with positive/Negative/neutral sentiment?

Coherence and Cohesion:
Essay topic to essay body coherence: 0.148054250014 0.272083759551 54% => OK
Sentence topic coherence: 0.0618642718982 0.0996497079465 62% => OK
Sentence topic coherence SD: 0.0424545393328 0.0662205650399 64% => OK
Paragraph topic coherence: 0.0846688359444 0.162205337803 52% => OK
Paragraph topic coherence SD: 0.0380072202271 0.0443174109184 86% => OK

Essay readability:
automated_readability_index: 13.8 13.3589403974 103% => OK
flesch_reading_ease: 55.58 53.8541721854 103% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 11.5 11.0289183223 104% => OK
coleman_liau_index: 11.38 12.2367328918 93% => OK
dale_chall_readability_score: 7.69 8.42419426049 91% => OK
difficult_words: 53.0 63.6247240618 83% => More difficult words wanted.
linsear_write_formula: 11.0 10.7273730684 103% => OK
gunning_fog: 11.6 10.498013245 110% => OK
text_standard: 12.0 11.2008830022 107% => OK
What are above readability scores?

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Rates: 73.3333333333 out of 100
Scores by essay e-grader: 22.0 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.