Populations of the yellow cedar, a species of tree that is common in northwestern North America, have been steadily declining for more than a century now, since about 1880. Scientists have advanced several hypotheses to explain this decline.
One hypothesis is that the yellow cedar decline may be caused by insect parasites, specifically the cedar bark beetle. This beetle is known to attack cedar trees; the beetle larvae eat the wood. There have been recorded instances of sustained beetle attacks overwhelming and killing yellow cedars, so this insect is a good candidate for the cause of the tree’s decline.
A second hypothesis attributes the decline to brown bears. Bears sometimes claw at the cedars in order to eat the tree bark, which has a high sugar content. In fact, the cedar bark can contain as much sugar as the wild berries that are a staple of the bears’ diet. Although the bears’ clawing is unlikely to destroy trees by itself, their aggressive feeding habits may critically weaken enough trees to be responsible for the decline.
The third hypothesis states that gradual changes of climate may be to blame. Over the last hundred years, the patterns of seasonal as well as day-to-day temperatures have changed in northwestern North America. These changes have affected the root systems of the yellow cedar trees: the fine surface roots now start growing in the late winter rather than in the early spring. The change in the timing of root growth may have significant consequences. Growing roots are sensitive and are therefore likely to suffer damage from partial freezing on clod winter nights. This frozen root damage may be capable of undermining the health of the whole tree, eventually killing it.
The reading mainly discusses three hypotheses that developed by scientists to explain a decline in the populations of a species of tree called yellow cedar that is mainly located in the northwestern north america. however, the professor in the lecture, tackles these three hypotheses and concludes that none of them is adequate for explaining the decrease in the populations of this species.
First, the first hypothesis mentioned in the passage was that the decline in the population is because of insect parasites, specifically, the cedar bark beetle. It is mentioned in the passage that there are recorded instances where the beetle attacking and killing yellow cedars. In the lecture, the professor refutes this by saying that this tree is more resistance to these kind of attacks than other species. Also, he states that these trees have powerful chemicals that they use to defend themselves against insect attacks. he suggests that these instances happened when the insects attacked already damaged or sick trees that would die anyways. so this can not be the reason of the decline in his opinion.
Second, the passage suggests that the reason for this decline may be caused by brown bears, as they claw at the cedars to eat tree bark and that their aggressive eating habits critically weaken the trees. On the other hand, the professor sees this evidence lacking important information, as the cedar trees are dying in the north america in both mainland and island. In islands there are no bears, however, the trees still suffer to survive, so we can conclude that this can not be a compelling reason for the decrease in the population.
Finally, the third hypothesis suggested in the passage is that the tree are suffering from freezing on cold winter nights and that the climate change is the main reason for that. In the passage, the professor states that more we observe more trees dying in the lower elevation where the weather is warmer than in higher elevations where the weather is colder. In this context, this hypothesis can not be reliable.
To recapitulate, the passage suggests three hypotheses that explain the decline in populations of the cedar trees. In the lecture, the professor refutes these three hypotheses one by one, stating the fallacious facts they rely upon.
| Post date | Users | Rates | Link to Content |
|---|---|---|---|
| 2020-01-24 | supergirl20 | 40 | view |
| 2020-01-11 | Raziya | 80 | view |
| 2020-01-05 | S M Naimul Mamun | 70 | view |
| 2019-11-27 | shingwa | 80 | view |
| 2019-11-21 | omarsamiiir | 73 | view |
- To understand the most important characteristics of a society, one must study its major cities. 16
- TPO 06_ Integrated Writing 3
- The following appeared in a magazine article about planning for retirement."Clearview should be a top choice for anyone seeking a place to retire, because it has spectacular natural beauty and a consistent climate. Another advantage is that housing costs 63
- Essay topics: TPO-05 - Integrated Writing Task 70
- Students should always question what they are taught instead of accepting it passively.Write a response in which you discuss the extent to which you agree or disagree with the statement and explain your reasoning for the position you take. In developing a 50
Grammar and spelling errors:
Line 1, column 215, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: However
...ated in the northwestern north america. however, the professor in the lecture, tackles ...
^^^^^^^
Line 3, column 371, Rule ID: THIS_NNS[2]
Message: Did you mean 'this kind' or 'these kinds'?
Suggestion: this kind; these kinds
...ng that this tree is more resistance to these kind of attacks than other species. Also, he...
^^^^^^^^^^
Line 3, column 480, Rule ID: USE_TO_VERB[1]
Message: Did you mean 'used'?
Suggestion: used
...trees have powerful chemicals that they use to defend themselves against insect att...
^^^
Line 3, column 529, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: He
...fend themselves against insect attacks. he suggests that these instances happened ...
^^
Line 3, column 651, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: So
...d or sick trees that would die anyways. so this can not be the reason of the decli...
^^
Transition Words or Phrases used:
also, anyway, finally, first, however, if, may, second, so, still, third, kind of, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 18.0 10.4613686534 172% => OK
Auxiliary verbs: 6.0 5.04856512141 119% => OK
Conjunction : 6.0 7.30242825607 82% => OK
Relative clauses : 22.0 12.0772626932 182% => OK
Pronoun: 44.0 22.412803532 196% => Less pronouns wanted
Preposition: 44.0 30.3222958057 145% => OK
Nominalization: 6.0 5.01324503311 120% => OK
Performance on vocabulary words:
No of characters: 1920.0 1373.03311258 140% => OK
No of words: 380.0 270.72406181 140% => Less content wanted.
Chars per words: 5.05263157895 5.08290768461 99% => OK
Fourth root words length: 4.41515443553 4.04702891845 109% => OK
Word Length SD: 2.58936670725 2.5805825403 100% => OK
Unique words: 175.0 145.348785872 120% => OK
Unique words percentage: 0.460526315789 0.540411800872 85% => More unique words wanted or less content wanted.
syllable_count: 594.9 419.366225166 142% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 12.0 8.23620309051 146% => OK
Subordination: 2.0 1.25165562914 160% => OK
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 7.0 2.5761589404 272% => Less preposition wanted as sentence beginnings.
Performance on sentences:
How many sentences: 16.0 13.0662251656 122% => OK
Sentence length: 23.0 21.2450331126 108% => OK
Sentence length SD: 44.8887513749 49.2860985944 91% => OK
Chars per sentence: 120.0 110.228320801 109% => OK
Words per sentence: 23.75 21.698381199 109% => OK
Discourse Markers: 6.25 7.06452816374 88% => OK
Paragraphs: 5.0 4.09492273731 122% => OK
Language errors: 5.0 4.19205298013 119% => OK
Sentences with positive sentiment : 2.0 4.33554083885 46% => More positive sentences wanted.
Sentences with negative sentiment : 7.0 4.45695364238 157% => OK
Sentences with neutral sentiment: 7.0 4.27373068433 164% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.280969035749 0.272083759551 103% => OK
Sentence topic coherence: 0.0953412490198 0.0996497079465 96% => OK
Sentence topic coherence SD: 0.0634578099314 0.0662205650399 96% => OK
Paragraph topic coherence: 0.162302488183 0.162205337803 100% => OK
Paragraph topic coherence SD: 0.0617142347352 0.0443174109184 139% => OK
Essay readability:
automated_readability_index: 14.2 13.3589403974 106% => OK
flesch_reading_ease: 48.13 53.8541721854 89% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 12.3 11.0289183223 112% => OK
coleman_liau_index: 12.31 12.2367328918 101% => OK
dale_chall_readability_score: 8.43 8.42419426049 100% => OK
difficult_words: 88.0 63.6247240618 138% => OK
linsear_write_formula: 15.0 10.7273730684 140% => OK
gunning_fog: 11.2 10.498013245 107% => OK
text_standard: 15.0 11.2008830022 134% => OK
What are above readability scores?
---------------------
Write the essay in 20 minutes.
Rates: 73.3333333333 out of 100
Scores by essay e-grader: 22.0 Out of 30
---------------------
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.