The sea otter is a small mammal that lives in waters along the western coast of North America from California to Alaska. When some sea otter populations off the Alaskan coast started rapidly declining a few years ago, it caused much concern because sea otters play an important ecological role in the coastal ecosystem. Experts started investigating the cause of the decline and quickly realized that there were two possible explanations: environmental pollution or attacks by predators. Initially, the pollution hypothesis seemed the more likely of the two.
The first reason why pollution seemed the more likely cause was that there were known sources of it along the Alaskan coast, such as oil rigs and other sources of industrial chemical pollution. Water samples from the area revealed increased levels of chemicals that could decrease the otters' resistance to life-threatening infections and thus could indirectly cause their deaths.
Second, other sea mammals such as seals and sea lions along the Alaskan coast were also declining, indicating that whatever had endangered the otters was affecting other sea mammals as well. This fact again pointed to environmental pollution, since it usually affects the entire ecosystem rather than a single species. Only widely occurring predators, such as the orca (a large predatory whale), could have the same effect, but orcas prefer to hunt much larger prey, such as other whales.
Third, scientists believed that the pollution hypothesis could also explain the uneven pattern of otter decline: at some Alaskan locations the otter populations declined greatly, while at others they remained stable. Some experts explained these observations by suggesting that ocean currents or other environmental factors may have created uneven concentrations of pollutants along the coast.
The passage states that the decline in sea otter population is due to environmental pollution and provides three reasons of support. However, the professor refutes this theory and claims that decline in number of sea otters is due to attacks by predators. She refutes the passage by giving three reasons.
First, the passage claims that environmental pollution was the cause for decline as there were known sources of oil rigs and industrial chemicals along the Alaskan coast. However the professor states that there were no bodies of dead sea otters found along the sea coast, which should have been found if pollution was the likely cause of their death. But this logic is consistent if the reason for the decline in their population was due to attacks by predators.
Second, the passage states that other sea mammals' numbers have also been declining and this kind of wide spread phenomenon can only be explained by pollution. The passage also states that predators like orca, found in the region only hunt larger prey, such as whales. However, the professor refutes this argument by stating that number of whales' population have gone down a lot due to hunting by humans. She states that this would have caused orca to hunt smaller prey including sea otter, seals and sea lions.
Third , the passage claims that uneven pattern of otter decline can be attributed to pollution hypothesis. However, the professor refutes this and states that predator theory would provide a better explanation for uneven pattern in decline. She further explains that decline in otters in consistent with locations where orca are found abundantly. She explains that orca have hunted sea otters from the regions which are easily accessible where the decline is high. In consistent with this, there is no decline in shallow or rocky regions where the orca cannot enter due to its size.
Thus professor refutes all the claims in passage and proves that the cause of the decline is
Grammar and spelling errors:
Line 5, column 172, Rule ID: SENT_START_CONJUNCTIVE_LINKING_ADVERB_COMMA[1]
Message: Did you forget a comma after a conjunctive/linking adverb?
Suggestion: However,
...rial chemicals along the Alaskan coast. However the professor states that there were no...
^^^^^^^
Line 9, column 43, Rule ID: POSSESIVE_APOSTROPHE[1]
Message: Possible typo: apostrophe is missing. Did you mean 'mammals'' or 'mammal's'?
Suggestion: mammals'; mammal's
...cond, the passage states that other sea mammals numbers have also been declining and th...
^^^^^^^
Line 13, column 6, Rule ID: COMMA_PARENTHESIS_WHITESPACE
Message: Put a space after the comma, but not before the comma
Suggestion: ,
...a otter, seals and sea lions. Third , the passage claims that uneven pattern ...
^^
Line 17, column 1, Rule ID: SENT_START_CONJUNCTIVE_LINKING_ADVERB_COMMA[1]
Message: Did you forget a comma after a conjunctive/linking adverb?
Suggestion: Thus,
...orca cannot enter due to its size. Thus professor refutes all the claims in pas...
^^^^
Transition Words or Phrases used:
also, but, first, however, if, second, so, third, thus, kind of, such as
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 17.0 10.4613686534 163% => OK
Auxiliary verbs: 6.0 5.04856512141 119% => OK
Conjunction : 9.0 7.30242825607 123% => OK
Relative clauses : 18.0 12.0772626932 149% => OK
Pronoun: 27.0 22.412803532 120% => Less pronouns wanted
Preposition: 39.0 30.3222958057 129% => OK
Nominalization: 10.0 5.01324503311 199% => OK
Performance on vocabulary words:
No of characters: 1654.0 1373.03311258 120% => OK
No of words: 327.0 270.72406181 121% => OK
Chars per words: 5.05810397554 5.08290768461 100% => OK
Fourth root words length: 4.25242769721 4.04702891845 105% => OK
Word Length SD: 2.39568002725 2.5805825403 93% => OK
Unique words: 145.0 145.348785872 100% => OK
Unique words percentage: 0.443425076453 0.540411800872 82% => More unique words wanted or less content wanted.
syllable_count: 506.7 419.366225166 121% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 8.0 8.23620309051 97% => OK
Subordination: 0.0 1.25165562914 0% => More 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: 16.0 13.0662251656 122% => OK
Sentence length: 20.0 21.2450331126 94% => OK
Sentence length SD: 30.3854791595 49.2860985944 62% => OK
Chars per sentence: 103.375 110.228320801 94% => OK
Words per sentence: 20.4375 21.698381199 94% => OK
Discourse Markers: 4.5 7.06452816374 64% => OK
Paragraphs: 5.0 4.09492273731 122% => OK
Language errors: 4.0 4.19205298013 95% => OK
Sentences with positive sentiment : 5.0 4.33554083885 115% => OK
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: 0.216119886637 0.272083759551 79% => OK
Sentence topic coherence: 0.0863879573925 0.0996497079465 87% => OK
Sentence topic coherence SD: 0.0705646848694 0.0662205650399 107% => OK
Paragraph topic coherence: 0.135365224347 0.162205337803 83% => OK
Paragraph topic coherence SD: 0.0532230313064 0.0443174109184 120% => OK
Essay readability:
automated_readability_index: 12.6 13.3589403974 94% => Automated_readability_index is low.
flesch_reading_ease: 59.64 53.8541721854 111% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 9.9 11.0289183223 90% => OK
coleman_liau_index: 12.07 12.2367328918 99% => OK
dale_chall_readability_score: 7.72 8.42419426049 92% => OK
difficult_words: 64.0 63.6247240618 101% => OK
linsear_write_formula: 10.5 10.7273730684 98% => OK
gunning_fog: 10.0 10.498013245 95% => OK
text_standard: 10.0 11.2008830022 89% => OK
What are above readability scores?
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Write the essay in 20 minutes.
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.