Seals, seal lions and sea otter populations started rapidly declining a few years ago. Summarize the points made in the lecture, being sure to explain how they respond to the specific points made in the reading passage.

Essay topics:

Seals, seal lions and sea otter populations started rapidly declining a few years ago. Summarize the points made in the lecture, being sure to explain how they respond to the specific points made in the reading passage.

阅读材料

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.

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Average: 9 (1 vote)
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Grammar and spelling errors:
Line 7, column 286, Rule ID: POSSESIVE_APOSTROPHE[1]
Message: Possible typo: apostrophe is missing. Did you mean 'otters'' or 'otter's'?
Suggestion: otters'; otter's
...ls of chemicals that could decrease the otters resistance to life-threatening infectio...
^^^^^^

Transition Words or Phrases used:
also, but, first, if, may, second, so, third, thus, well, while, such as

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

Performance on Part of Speech:
To be verbs : 6.0 10.4613686534 57% => More to be verbs wanted.
Auxiliary verbs: 5.0 5.04856512141 99% => OK
Conjunction : 7.0 7.30242825607 96% => OK
Relative clauses : 8.0 12.0772626932 66% => More relative clauses wanted.
Pronoun: 14.0 22.412803532 62% => OK
Preposition: 26.0 30.3222958057 86% => OK
Nominalization: 7.0 5.01324503311 140% => OK

Performance on vocabulary words:
No of characters: 1572.0 1373.03311258 114% => OK
No of words: 282.0 270.72406181 104% => OK
Chars per words: 5.57446808511 5.08290768461 110% => OK
Fourth root words length: 4.09790868904 4.04702891845 101% => OK
Word Length SD: 2.77814418387 2.5805825403 108% => OK
Unique words: 173.0 145.348785872 119% => OK
Unique words percentage: 0.613475177305 0.540411800872 114% => OK
syllable_count: 483.3 419.366225166 115% => OK
avg_syllables_per_word: 1.7 1.55342163355 109% => OK

A sentence (or a clause, phrase) starts by:
Pronoun: 2.0 3.25607064018 61% => OK
Article: 3.0 8.23620309051 36% => 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: 11.0 13.0662251656 84% => Need more sentences. Double check the format of sentences, make sure there is a space between two sentences, or have enough periods. And also check the lengths of sentences, maybe they are too long.
Sentence length: 25.0 21.2450331126 118% => OK
Sentence length SD: 39.3002849442 49.2860985944 80% => OK
Chars per sentence: 142.909090909 110.228320801 130% => OK
Words per sentence: 25.6363636364 21.698381199 118% => OK
Discourse Markers: 6.54545454545 7.06452816374 93% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 1.0 4.19205298013 24% => OK
Sentences with positive sentiment : 5.0 4.33554083885 115% => OK
Sentences with negative sentiment : 1.0 4.45695364238 22% => More negative sentences wanted.
Sentences with neutral sentiment: 5.0 4.27373068433 117% => OK
What are sentences with positive/Negative/neutral sentiment?

Coherence and Cohesion:
Essay topic to essay body coherence: 0.157766265416 0.272083759551 58% => OK
Sentence topic coherence: 0.0571838218363 0.0996497079465 57% => OK
Sentence topic coherence SD: 0.0640979078545 0.0662205650399 97% => OK
Paragraph topic coherence: 0.0911842405553 0.162205337803 56% => OK
Paragraph topic coherence SD: 0.0570695473915 0.0443174109184 129% => OK

Essay readability:
automated_readability_index: 17.6 13.3589403974 132% => OK
flesch_reading_ease: 37.64 53.8541721854 70% => OK
smog_index: 11.2 5.55761589404 202% => Smog_index is high.
flesch_kincaid_grade: 14.2 11.0289183223 129% => OK
coleman_liau_index: 15.32 12.2367328918 125% => OK
dale_chall_readability_score: 9.97 8.42419426049 118% => OK
difficult_words: 91.0 63.6247240618 143% => OK
linsear_write_formula: 12.0 10.7273730684 112% => OK
gunning_fog: 12.0 10.498013245 114% => OK
text_standard: 12.0 11.2008830022 107% => OK
What are above readability scores?

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Rates: 90.0 out of 100
Scores by essay e-grader: 27.0 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.