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 mussel，s 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 inthe past strongly suggests that the species will soon colonize all of North America.
Moreover, once zebra mussels are carried to a new habitat, theycan 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 reading discusses a fascinating topic pertaining to the population of the zebra mussel are apreading out and by its invasion, treath the freshwater fish population in North America, so, in the reading provides several reasons of support. In contrast, in the lecture, the professor believes that in the past the population of zebra mussel were unstopable due to lack of the appropriate knowledge, hence, opposes each of the author's reasons.
First, the author of the reading points out that the plethora zebra mussel have been transported with ballast water with ship which were move across Europe's waterways to the North of America. However, the professor explains that the ballast water will be replaced with ocean water during this time and the solt water will kill the amount of aibra mussel; thus, during this transportation a majority of zebra mussel will die.
Furthermore, the author of the reading believes that in the new habitat, zebra mussel reproduce very quickly, also, they do not have predator in this area. But professor suggests that this is not acceptable because in the new habitat a one type of bird species change their diet when they can not find the food, hence, the zibra mussel have been eaten by them and their population will be reduced.
Finally, the author of the reading believes that the population of zibra mussels have negative effect on the fishes due to both of them have the same source of food and eat the plankton. But the profossor explains that maybe they jave negative effect on some type of fish but they will have positive effect on the bottom of the fish pop
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Grammar and spelling errors:
Line 3, column 138, Rule ID: BEEN_PART_AGREEMENT[1]
Message: Consider using a past participle here: 'moved'.
Suggestion: moved
...with ballast water with ship which were move across Europes waterways to the North o...
^^^^
Transition Words or Phrases used:
also, but, finally, first, furthermore, hence, however, may, so, thus, in contrast
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 8.0 10.4613686534 76% => OK
Auxiliary verbs: 6.0 5.04856512141 119% => OK
Conjunction : 7.0 7.30242825607 96% => OK
Relative clauses : 9.0 12.0772626932 75% => More relative clauses wanted.
Pronoun: 20.0 22.412803532 89% => OK
Preposition: 43.0 30.3222958057 142% => OK
Nominalization: 6.0 5.01324503311 120% => OK
Performance on vocabulary words:
No of characters: 1342.0 1373.03311258 98% => OK
No of words: 274.0 270.72406181 101% => OK
Chars per words: 4.89781021898 5.08290768461 96% => OK
Fourth root words length: 4.0685311056 4.04702891845 101% => OK
Word Length SD: 2.44960937147 2.5805825403 95% => OK
Unique words: 134.0 145.348785872 92% => More unique words wanted.
Unique words percentage: 0.489051094891 0.540411800872 90% => More unique words wanted or less content wanted.
syllable_count: 417.6 419.366225166 100% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 1.0 3.25607064018 31% => OK
Article: 7.0 8.23620309051 85% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 2.0 1.51434878587 132% => OK
Preposition: 4.0 2.5761589404 155% => OK
Performance on sentences:
How many sentences: 8.0 13.0662251656 61% => 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: 34.0 21.2450331126 160% => The Avg. Sentence Length is relatively long.
Sentence length SD: 34.0734500748 49.2860985944 69% => OK
Chars per sentence: 167.75 110.228320801 152% => OK
Words per sentence: 34.25 21.698381199 158% => OK
Discourse Markers: 10.25 7.06452816374 145% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 1.0 4.19205298013 24% => OK
Sentences with positive sentiment : 2.0 4.33554083885 46% => More positive sentences wanted.
Sentences with negative sentiment : 4.0 4.45695364238 90% => OK
Sentences with neutral sentiment: 2.0 4.27373068433 47% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.185421300756 0.272083759551 68% => OK
Sentence topic coherence: 0.0878243717297 0.0996497079465 88% => OK
Sentence topic coherence SD: 0.0484952129979 0.0662205650399 73% => OK
Paragraph topic coherence: 0.113963244275 0.162205337803 70% => OK
Paragraph topic coherence SD: 0.0527559196956 0.0443174109184 119% => OK
Essay readability:
automated_readability_index: 18.8 13.3589403974 141% => OK
flesch_reading_ease: 45.43 53.8541721854 84% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 15.4 11.0289183223 140% => OK
coleman_liau_index: 11.73 12.2367328918 96% => OK
dale_chall_readability_score: 8.67 8.42419426049 103% => OK
difficult_words: 58.0 63.6247240618 91% => OK
linsear_write_formula: 19.0 10.7273730684 177% => OK
gunning_fog: 15.6 10.498013245 149% => OK
text_standard: 19.0 11.2008830022 170% => OK
What are above readability scores?
---------------------
Rates: 76.6666666667 out of 100
Scores by essay e-grader: 23.0 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.