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

According to the reading passage, it is stated that there are some reliable theories about the reasons why Steller's sea cows extincted. However, the professor in the listening part explains why the assumptions mentioned in the reading passage were incorrect and refutes them by developing three reasons as follows.
Fisrt of all, the reading passage claims that sea cows may be overhunted by native people due to the fact that they were a good source of nutrition. On the other hand, the professor casts doubt on this point by mentioning that sea cows were massive and heavy animals, which usually were in a length of nine meters. Therefore, one sea cow could provide enough nutrition for the small vilage dwellers for weeks, and there was no need to overhunt them.
Secondly, the reading posits that the sea cows may extincted because of the ecosystem disturbances. Moreover, kelp, which was one of their vital nutrition source, could easily disturbed by ecological changes. In contrast, the lecturer states that if there was some severe changes in ecological situations, it would influence other creatures, too. There is no evidence of decline in other animals such as some marine animals, like whale. Besides, since there was no noticable change in ecological conditions,there was no decreas in the amount of kelp, and they could not affect sea cows' extinction.
Finally, the reading says that the emmerge of European fur traders with weapons to the sea cows' lands, may brought sea caws about extinction. The professor opposes this idea by mentioning that sea cows had experienced decline in their population before the fur traders advent. As a result, fur traders should not be accepted as the main reason for their extinction.

Votes
Average: 8.5 (1 vote)
Essay Categories
Essays by the user:

Grammar and spelling errors:
Line 3, column 177, Rule ID: DID_BASEFORM[1]
Message: The verb 'could' requires the base form of the verb: 'disturb'
Suggestion: disturb
...ir vital nutrition source, could easily disturbed by ecological changes. In contrast, the...
^^^^^^^^^
Line 3, column 507, Rule ID: COMMA_PARENTHESIS_WHITESPACE
Message: Put a space after the comma
Suggestion: , there
...oticable change in ecological conditions,there was no decreas in the amount of kelp, a...
^^^^^^
Line 4, column 262, Rule ID: POSSESIVE_APOSTROPHE[2]
Message: Possible typo: apostrophe is missing. Did you mean 'traders'' or 'trader's'?
Suggestion: traders'; trader's
...line in their population before the fur traders advent. As a result, fur traders should...
^^^^^^^
Line 4, column 367, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...s the main reason for their extinction.
^^^

Transition Words or Phrases used:
besides, finally, however, if, may, moreover, second, secondly, so, therefore, well, in contrast, such as, as a result, on the other hand

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

Performance on Part of Speech:
To be verbs : 14.0 10.4613686534 134% => OK
Auxiliary verbs: 9.0 5.04856512141 178% => OK
Conjunction : 4.0 7.30242825607 55% => More conjunction wanted.
Relative clauses : 10.0 12.0772626932 83% => OK
Pronoun: 19.0 22.412803532 85% => OK
Preposition: 34.0 30.3222958057 112% => OK
Nominalization: 9.0 5.01324503311 180% => OK

Performance on vocabulary words:
No of characters: 1452.0 1373.03311258 106% => OK
No of words: 285.0 270.72406181 105% => OK
Chars per words: 5.09473684211 5.08290768461 100% => OK
Fourth root words length: 4.10876417139 4.04702891845 102% => OK
Word Length SD: 2.64092842084 2.5805825403 102% => OK
Unique words: 155.0 145.348785872 107% => OK
Unique words percentage: 0.543859649123 0.540411800872 101% => OK
syllable_count: 445.5 419.366225166 106% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK

A sentence (or a clause, phrase) starts by:
Pronoun: 2.0 3.25607064018 61% => OK
Article: 7.0 8.23620309051 85% => OK
Subordination: 2.0 1.25165562914 160% => OK
Conjunction: 2.0 1.51434878587 132% => OK
Preposition: 5.0 2.5761589404 194% => OK

Performance on sentences:
How many sentences: 13.0 13.0662251656 99% => OK
Sentence length: 21.0 21.2450331126 99% => OK
Sentence length SD: 27.4814622833 49.2860985944 56% => The essay contains lots of sentences with the similar length. More sentence varieties wanted.
Chars per sentence: 111.692307692 110.228320801 101% => OK
Words per sentence: 21.9230769231 21.698381199 101% => OK
Discourse Markers: 10.5384615385 7.06452816374 149% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 4.0 4.19205298013 95% => OK
Sentences with positive sentiment : 4.0 4.33554083885 92% => OK
Sentences with negative sentiment : 6.0 4.45695364238 135% => OK
Sentences with neutral sentiment: 3.0 4.27373068433 70% => OK
What are sentences with positive/Negative/neutral sentiment?

Coherence and Cohesion:
Essay topic to essay body coherence: 0.153461811236 0.272083759551 56% => OK
Sentence topic coherence: 0.0570729278483 0.0996497079465 57% => OK
Sentence topic coherence SD: 0.0340944669645 0.0662205650399 51% => OK
Paragraph topic coherence: 0.0883926610873 0.162205337803 54% => OK
Paragraph topic coherence SD: 0.031479920011 0.0443174109184 71% => OK

Essay readability:
automated_readability_index: 13.5 13.3589403974 101% => OK
flesch_reading_ease: 50.16 53.8541721854 93% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 11.5 11.0289183223 104% => OK
coleman_liau_index: 12.24 12.2367328918 100% => OK
dale_chall_readability_score: 8.78 8.42419426049 104% => OK
difficult_words: 74.0 63.6247240618 116% => OK
linsear_write_formula: 13.0 10.7273730684 121% => OK
gunning_fog: 10.4 10.498013245 99% => OK
text_standard: 13.0 11.2008830022 116% => OK
What are above readability scores?

---------------------

Rates: 85.0 out of 100
Scores by essay e-grader: 25.5 Out of 30
---------------------
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.