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 ot

Essay topics:

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.

Both, the reading and the lecture, talk about the most probable cause of the decreasing presence of otters along the western coast of North America. While the reading states that the most logic anwer is the pollution, the professor points toward predators as the most reasonable origin of that phenomenon, and refutes each argument presented, casting doubts in the author’s beliefs.

Firstly, the reading points out that exist many pollutions sources along Alaska cost, such as oil rigs and other sources of industrial chemical pollution. However, the lecturer disproves this by stating that there are not proves of that theory, like dead bodies on the beack, which would be consistent with that cause. Furthermore, the ausence of bodies is, in fact, a prove that lean the balance toward predectors theory, owing ot they eat it completely.

Secondly, the text argues that not only otters are clearly decreasing, but also others mammals like sea lions or seals, which prove that the source is affectign the entire ecosystem. Nonetheless, the professor mention that the orcas could be hunting smaller mammals as a result of the reduction of their natural preys, due to the human’s uncontrolled fishing.

Finally, the writer says that the unregular pattern of the otter decleaning explain the pollution hypotesis. this is because the ocean currents and others factor affect those areas with different intensities. Notwithstanding, the lecturer remarks the weakness of this point noting that, those areas where the otter populations is stable, are rocky zones, which are less accessible to the orcas. On the other hand, areas where otter are almos desapear, have excellent conditions as orcas’ hunting area.

Votes
Average: 8 (1 vote)
Essay Categories

Comments

Grammar and spelling errors:
Line 5, column 368, Rule ID: A_INFINITVE[1]
Message: Probably a wrong construction: a/the + infinitive
...ore, the ausence of bodies is, in fact, a prove that lean the balance toward predectors...
^^^^^^^
Line 13, column 110, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: This
...eaning explain the pollution hypotesis. this is because the ocean currents and other...
^^^^

Transition Words or Phrases used:
also, but, finally, first, firstly, furthermore, however, if, nonetheless, second, secondly, so, while, in fact, such as, as a result, on the other hand

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

Performance on Part of Speech:
To be verbs : 12.0 10.4613686534 115% => OK
Auxiliary verbs: 2.0 5.04856512141 40% => OK
Conjunction : 6.0 7.30242825607 82% => OK
Relative clauses : 17.0 12.0772626932 141% => OK
Pronoun: 20.0 22.412803532 89% => OK
Preposition: 28.0 30.3222958057 92% => OK
Nominalization: 9.0 5.01324503311 180% => OK

Performance on vocabulary words:
No of characters: 1463.0 1373.03311258 107% => OK
No of words: 271.0 270.72406181 100% => OK
Chars per words: 5.39852398524 5.08290768461 106% => OK
Fourth root words length: 4.05734859645 4.04702891845 100% => OK
Word Length SD: 2.67564573101 2.5805825403 104% => OK
Unique words: 170.0 145.348785872 117% => OK
Unique words percentage: 0.627306273063 0.540411800872 116% => OK
syllable_count: 437.4 419.366225166 104% => 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: 10.0 8.23620309051 121% => OK
Subordination: 1.0 1.25165562914 80% => OK
Conjunction: 2.0 1.51434878587 132% => OK
Preposition: 3.0 2.5761589404 116% => OK

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: 24.0 21.2450331126 113% => OK
Sentence length SD: 39.2544149225 49.2860985944 80% => OK
Chars per sentence: 133.0 110.228320801 121% => OK
Words per sentence: 24.6363636364 21.698381199 114% => OK
Discourse Markers: 13.8181818182 7.06452816374 196% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 2.0 4.19205298013 48% => OK
Sentences with positive sentiment : 3.0 4.33554083885 69% => OK
Sentences with negative sentiment : 3.0 4.45695364238 67% => OK
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: 0.144496573341 0.272083759551 53% => OK
Sentence topic coherence: 0.0513258708611 0.0996497079465 52% => OK
Sentence topic coherence SD: 0.0587390181711 0.0662205650399 89% => OK
Paragraph topic coherence: 0.0771010735296 0.162205337803 48% => OK
Paragraph topic coherence SD: 0.0302953527316 0.0443174109184 68% => OK

Essay readability:
automated_readability_index: 16.3 13.3589403974 122% => OK
flesch_reading_ease: 47.12 53.8541721854 87% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 12.7 11.0289183223 115% => OK
coleman_liau_index: 14.34 12.2367328918 117% => OK
dale_chall_readability_score: 10.01 8.42419426049 119% => OK
difficult_words: 89.0 63.6247240618 140% => OK
linsear_write_formula: 13.5 10.7273730684 126% => OK
gunning_fog: 11.6 10.498013245 110% => OK
text_standard: 14.0 11.2008830022 125% => OK
What are above readability scores?

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Rates: 80.0 out of 100
Scores by essay e-grader: 24.0 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.