The lecture and the reading debate the reasons why the marine mammal known as Stelle's sea cow became extinct in 1768. The author of the reading believes that there are three main causes for that. On the other hand, the lecturer thinks that the claims made in the article might be not true.
First of all, the author says that the extinction of the sea cows is the result of their overhunting by groups of native Siberian people. In the lecture is argued that these creatures were massive; therefore, one sea cow could have fed the Siberian population for a month, so there was no reason to hunt them all.
Second, the author exposes the theory of the ecosystem disturbance, which holds that the decline of sea cows may be due to some disturbance that negatively affected their main source of food, kelps. The lecturer rebuts this claim and she explains that an ecosystem disturbance would have affected the broader ecosystem and not only the kelps, in fact, it is not reported any decline of other mammals such as whales.
Finally, the lecturer also excludes the third and last explanations proposed by the author. She excludes that the extinction of sea cows is due to the arrival of European fur traders to the island after 1741. They possessed weapons that allow them to kill a large number animals in a short time. She points out that the population of sea cows was already reduced when the traders arrived, therefore something else must have happened long before the arrival of European. She concludes by saying that the reasons are still unclear.
- TPO-34 - Independent Writing Task Do you agree or disagree with the following statement?Educating children is a more difficult task today than it was in the past because they spend so much time on cell phone, online games, and social networking Web site.U 76
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- TPO-28 - Integrated Writing Task Robert E. Peary was a well-known adventurer and arctic explorer who in 1909 set out to reach the North Pole. When he returned from the expedition, he claimed to have reached the pole on April 7, 1909. This report made him 76
Transition Words or Phrases used:
also, but, finally, first, may, second, so, still, therefore, third, in fact, such as, first of all, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 11.0 10.4613686534 105% => OK
Auxiliary verbs: 5.0 5.04856512141 99% => OK
Conjunction : 4.0 7.30242825607 55% => More conjunction wanted.
Relative clauses : 14.0 12.0772626932 116% => OK
Pronoun: 24.0 22.412803532 107% => OK
Preposition: 30.0 30.3222958057 99% => OK
Nominalization: 7.0 5.01324503311 140% => OK
Performance on vocabulary words:
No of characters: 1296.0 1373.03311258 94% => OK
No of words: 270.0 270.72406181 100% => OK
Chars per words: 4.8 5.08290768461 94% => OK
Fourth root words length: 4.05360046442 4.04702891845 100% => OK
Word Length SD: 2.34903593452 2.5805825403 91% => OK
Unique words: 153.0 145.348785872 105% => OK
Unique words percentage: 0.566666666667 0.540411800872 105% => OK
syllable_count: 396.0 419.366225166 94% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 5.0 3.25607064018 154% => OK
Article: 7.0 8.23620309051 85% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 3.0 2.5761589404 116% => OK
Performance on sentences:
How many sentences: 12.0 13.0662251656 92% => OK
Sentence length: 22.0 21.2450331126 104% => OK
Sentence length SD: 49.1118338308 49.2860985944 100% => OK
Chars per sentence: 108.0 110.228320801 98% => OK
Words per sentence: 22.5 21.698381199 104% => OK
Discourse Markers: 9.83333333333 7.06452816374 139% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 0.0 4.19205298013 0% => OK
Sentences with positive sentiment : 1.0 4.33554083885 23% => More positive sentences wanted.
Sentences with negative sentiment : 5.0 4.45695364238 112% => OK
Sentences with neutral sentiment: 6.0 4.27373068433 140% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.458060572072 0.272083759551 168% => OK
Sentence topic coherence: 0.15508595975 0.0996497079465 156% => OK
Sentence topic coherence SD: 0.110507823994 0.0662205650399 167% => OK
Paragraph topic coherence: 0.260025875887 0.162205337803 160% => OK
Paragraph topic coherence SD: 0.0616644596406 0.0443174109184 139% => OK
Essay readability:
automated_readability_index: 12.4 13.3589403974 93% => Automated_readability_index is low.
flesch_reading_ease: 57.61 53.8541721854 107% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 10.7 11.0289183223 97% => OK
coleman_liau_index: 10.86 12.2367328918 89% => OK
dale_chall_readability_score: 7.94 8.42419426049 94% => OK
difficult_words: 55.0 63.6247240618 86% => OK
linsear_write_formula: 10.5 10.7273730684 98% => OK
gunning_fog: 10.8 10.498013245 103% => OK
text_standard: 11.0 11.2008830022 98% => OK
What are above readability scores?
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Rates: 76.6666666667 out of 100
Scores by essay e-grader: 23.0 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.