The zebra mussel, a freshwater shellfish native to Eastern Europe, has long been spreading out from its original habitats and has now reached parts of North America. There are reasons to believe that this invasion cannot be stopped and that it poses a serious threat to freshwater fish populations in all of North America.
First, the history of the zebra mussel's spread suggests that the invasion might be unstoppable. It is a prime example of an invasion made possible by human transportation. From the zebra mussels original habitats in Eastern Europe, ships helped spread it out along new canals built to connect Europe’s waterways. The mussel can attach itself to a ship’ s bottom or can survive in the water - called "ballast water” - that the ship needs to take on to properly balance its cargo. By the early nineteenth century, the mussel had spread to the whole of Europe. It was later carried to the east coast of North America in the ballast water of ships traveling from Europe. The way ships have spread the zebra mussel in the past strongly suggests that the species will soon colonize all of North America.
Moreover, once zebra mussels are carried to a new habitat, they can dominate it. They are a hardy species that does well under a variety of conditions, and they have a high rate of reproduction. Most important, however, zebra mussels often have no predators in their new habitats, and species without natural predators are likely to dominate their habitats.
Finally, zebra mussels are likely to cause a decline in the overall fish population in habitats where they become dominant. The mussels are plankton eaters, which means that they compete for food with many freshwater fish species.
The article states that Zebra mussels are the main reasons for the declination of North American's freshwater fish population and it would not possible to their invasion then provides three reasons of support.
The lecturer challenges the claims made by the author. He explains that now it is possible to control the zebra mussels population in freshwater. so they are not responsible for freshwater fish declination and refutes each of the author's claims.
First of all, the article argues that ballast water of ships travel from Europe have the spread
Zebra mussel in North America freshwater. This specific argument is challenged by the lecturer.
He says that although it is true that invasion could not possible to control in past but today have enough knowledge like ships take water in empty space for balance the ships. so they put this water in the ocean of North America instead of freshwater That's why it is possible to control the mussel invasion because saltwater destroy Zebra mussel.
Secondly, the article states that Zebra mussel has enough adaptability under a variety of conditions. so, they can dominate the new condition. Moreover, the article said that Zebra mussel is likely to dominate their new environment because no natural predators are present there. The lecturer, however, rebuts this claim that this domination happening only at the beginning of the time when local aquatic birds have not enough notice Zebra mussels but after that, they can notice then change their habitation and like to eat more mussels. As a result, Zebra mussels would have controlled.
Finally, the article posits that Zebra mussels are the main responsible for the declination of fish in North America freshwater habitats. additionally, the article says that mussels also compete for food like plankton-eating with many fish species and decline their populations. In contrast, the lecturer says that though mussels like to eat some kinds of fish in freshwater habitats, they have provided benefits to some other kinds of fish. He elaborates on this point by bringing up the point that by the eating fish mussels also produces some nutrients like they produce food for the bottom layer of fish population.
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Grammar and spelling errors:
Line 3, column 147, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: So
...zebra mussels population in freshwater. so they are not responsible for freshwater...
^^
Line 11, column 96, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...ships travel from Europe have the spread Zebra mussel in North America freshwater...
^^^^
Line 15, column 178, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: So
...r in empty space for balance the ships. so they put this water in the ocean of Nor...
^^
Line 15, column 253, Rule ID: EN_CONTRACTION_SPELLING
Message: Possible spelling mistake found
Suggestion: That's
... of North America instead of freshwater Thats why it is possible to control the musse...
^^^^^
Line 19, column 103, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: So
...tability under a variety of conditions. so, they can dominate the new condition. M...
^^
Line 23, column 139, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: Additionally
...h in North America freshwater habitats. additionally, the article says that mussels also com...
^^^^^^^^^^^^
Transition Words or Phrases used:
also, but, finally, first, however, if, moreover, second, secondly, so, then, in contrast, as a result, first of all, it is true
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 9.0 10.4613686534 86% => OK
Auxiliary verbs: 5.0 5.04856512141 99% => OK
Conjunction : 6.0 7.30242825607 82% => OK
Relative clauses : 14.0 12.0772626932 116% => OK
Pronoun: 35.0 22.412803532 156% => Less pronouns wanted
Preposition: 46.0 30.3222958057 152% => OK
Nominalization: 12.0 5.01324503311 239% => Less nominalizations (nouns with a suffix like: tion ment ence ance) wanted.
Performance on vocabulary words:
No of characters: 1878.0 1373.03311258 137% => OK
No of words: 359.0 270.72406181 133% => OK
Chars per words: 5.23119777159 5.08290768461 103% => OK
Fourth root words length: 4.35284910392 4.04702891845 108% => OK
Word Length SD: 2.59259509685 2.5805825403 100% => OK
Unique words: 171.0 145.348785872 118% => OK
Unique words percentage: 0.476323119777 0.540411800872 88% => More unique words wanted or less content wanted.
syllable_count: 576.0 419.366225166 137% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 7.0 3.25607064018 215% => Less pronouns wanted as sentence beginning.
Article: 9.0 8.23620309051 109% => OK
Subordination: 1.0 1.25165562914 80% => OK
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 1.0 2.5761589404 39% => More preposition wanted as sentence beginning.
Performance on sentences:
How many sentences: 17.0 13.0662251656 130% => OK
Sentence length: 21.0 21.2450331126 99% => OK
Sentence length SD: 59.1341797193 49.2860985944 120% => OK
Chars per sentence: 110.470588235 110.228320801 100% => OK
Words per sentence: 21.1176470588 21.698381199 97% => OK
Discourse Markers: 7.52941176471 7.06452816374 107% => OK
Paragraphs: 7.0 4.09492273731 171% => Less paragraphs wanted.
Language errors: 6.0 4.19205298013 143% => OK
Sentences with positive sentiment : 8.0 4.33554083885 185% => 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: 0.181816643583 0.272083759551 67% => OK
Sentence topic coherence: 0.0711730758465 0.0996497079465 71% => OK
Sentence topic coherence SD: 0.0574116340852 0.0662205650399 87% => OK
Paragraph topic coherence: 0.111276213653 0.162205337803 69% => OK
Paragraph topic coherence SD: 0.041971584006 0.0443174109184 95% => OK
Essay readability:
automated_readability_index: 13.8 13.3589403974 103% => OK
flesch_reading_ease: 50.16 53.8541721854 93% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 11.5 11.0289183223 104% => OK
coleman_liau_index: 13.05 12.2367328918 107% => OK
dale_chall_readability_score: 8.06 8.42419426049 96% => OK
difficult_words: 77.0 63.6247240618 121% => OK
linsear_write_formula: 8.5 10.7273730684 79% => OK
gunning_fog: 10.4 10.498013245 99% => OK
text_standard: 9.0 11.2008830022 80% => OK
What are above readability scores?
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Write the essay in 20 minutes.
Maximum four paragraphs wanted.
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.