阅读材料
Agnostids were a group of marine animals that became extinct about 450 million years ago. Agnostid fossils can be found in rocks in many areas around the world. From the fossil remains, we know that agnostids were primitive arthropods—relatives of modern-day insects. However, the fossil information does not allow paleontologists to determine with certainty what agnostids ate or how they behaved. There are several different theories about how agnostids may have lived.
Free-Swimming Predators
First, the agnostids may have been free-swimming predators that hunted smaller animals. It is known that other types of primitive arthropods were strong swimmers and active predators, so it is reasonable that the agnostids may have lived that way as well. And while the agnostids were small, sometimes just six millimeters long, there were plenty of smaller organisms in the ancient ocean for them to prey on.
Seafloor Dwellers
Second, they may have dwelled on the seafloor. Again, there are examples of other types of primitive arthropods living this way, so it is possible that agnostids did too. On the seafloor they would have survived by scavenging dead organisms or by grazing on bacteria.
Parasites
Third, there is the possibility that the agnostids were parasites, living on and feeding off larger organisms. One reason that this seems possible is that there are many species of modern-day arthropods that exist as parasites, such as fleas, ticks, and mites. The agnostids might have lived on primitive fish or even on other, larger arthropods.
Both the reading material and the lecture are related to how the primitive arthropods, the agnostids, live. The author of the reading suggests three theory that might explain the living style of agnostids back in 450 million years ago, on the other hand, the lecturer rebuts each of the theory for some weakness they present.
To start with, the author proposes that the agnostids may be free-swimming predators that feed on smaller organisms in the ancient ocean. However, this theory is refused in the lecture since normally all the predator would have excellent eye sight that enables hunting. The agnostids, on the other hand, is poor-sighted, almost blind. Thus, it would be impossible to suggest they are free-swimming predators without other sensors found.
Next, another theory claims that the agnostids may have dwelled on the seafloor feeding on dead bodies and bacteria. This is also rejected by the lecturer, saying that typically this kind of dweller is often found localized in few areas due to their slow mobility, whereas the agnostids shows the opposite, occupying places distant from each other. The fast moving ability that this organism has then rules out the possibility that they are seafloor dwellers.
Finally, the lecturer points out that the group of parasites are usually small, yet the number of agnostids found is rather enormous, thus they would not have been parasites in the ancient time. If the agnostids were really parasites, they would have killed off many organisms due to the size of their group. In conclusion, the lecturer believes that this theory is not convincing.
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| 2023-09-05 | YasamanEsml | 86 | view |
| 2023-06-19 | Vivian Chang | 76 | view |
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| 2023-01-30 | reza_fattahi | 86 | view |
| 2023-01-30 | reza_fattahi | 75 | view |
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Grammar and spelling errors:
Line 3, column 239, Rule ID: EYE_BROW[1]
Message: This word is usually spelt together: 'eyesight'.
Suggestion: eyesight
...y all the predator would have excellent eye sight that enables hunting. The agnostids, on...
^^^^^^^^^
Transition Words or Phrases used:
also, but, finally, however, if, may, really, so, then, thus, well, whereas, in conclusion, kind of, to start with, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 14.0 10.4613686534 134% => OK
Auxiliary verbs: 7.0 5.04856512141 139% => OK
Conjunction : 3.0 7.30242825607 41% => More conjunction wanted.
Relative clauses : 10.0 12.0772626932 83% => OK
Pronoun: 23.0 22.412803532 103% => OK
Preposition: 32.0 30.3222958057 106% => OK
Nominalization: 0.0 5.01324503311 0% => More nominalizations (nouns with a suffix like: tion ment ence ance) wanted.
Performance on vocabulary words:
No of characters: 1355.0 1373.03311258 99% => OK
No of words: 262.0 270.72406181 97% => OK
Chars per words: 5.17175572519 5.08290768461 102% => OK
Fourth root words length: 4.02323427807 4.04702891845 99% => OK
Word Length SD: 2.50559946313 2.5805825403 97% => OK
Unique words: 149.0 145.348785872 103% => OK
Unique words percentage: 0.568702290076 0.540411800872 105% => OK
syllable_count: 399.6 419.366225166 95% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 8.0 8.23620309051 97% => OK
Subordination: 1.0 1.25165562914 80% => OK
Conjunction: 1.0 1.51434878587 66% => OK
Preposition: 4.0 2.5761589404 155% => OK
Performance on sentences:
How many sentences: 12.0 13.0662251656 92% => OK
Sentence length: 21.0 21.2450331126 99% => OK
Sentence length SD: 51.4783530558 49.2860985944 104% => OK
Chars per sentence: 112.916666667 110.228320801 102% => OK
Words per sentence: 21.8333333333 21.698381199 101% => OK
Discourse Markers: 11.0833333333 7.06452816374 157% => 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 : 4.0 4.45695364238 90% => 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: 0.171701352368 0.272083759551 63% => OK
Sentence topic coherence: 0.058866634285 0.0996497079465 59% => OK
Sentence topic coherence SD: 0.0505451308969 0.0662205650399 76% => OK
Paragraph topic coherence: 0.103973355349 0.162205337803 64% => OK
Paragraph topic coherence SD: 0.0294364459298 0.0443174109184 66% => OK
Essay readability:
automated_readability_index: 13.8 13.3589403974 103% => OK
flesch_reading_ease: 58.62 53.8541721854 109% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 10.3 11.0289183223 93% => OK
coleman_liau_index: 12.71 12.2367328918 104% => OK
dale_chall_readability_score: 8.35 8.42419426049 99% => OK
difficult_words: 61.0 63.6247240618 96% => OK
linsear_write_formula: 12.5 10.7273730684 117% => OK
gunning_fog: 10.4 10.498013245 99% => OK
text_standard: 13.0 11.2008830022 116% => OK
What are above readability scores?
---------------------
Rates: 85.0 out of 100
Scores by essay e-grader: 25.5 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.