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.
The lifestyle of Agnostids is a topic of much debate among paleontologists, as there is limited information to determine their food regimes or behavior with certainty. In the reading passage, the writer presents several theories about Agnostids' habitats, but the lecturer in the listening passage refutes them as flawed.
The reading suggests that Agnostids may have been free-swimming predators, as primitive arthropods were active hunters. However, the lecturer highlights the lack of necessary attributes, such as large eyes and hunting organs, in Agnostids, and argues that they were blind and not equipped for hunting.
Another theory, presented by the writer, is that Agnostids lived on the sea floor and survived by eating dead organisms or grazing on bacteria. The lecturer disagrees, pointing out the fast movement of Agnostids, which is not typical of sea floor animals that remain in a limited area.
Finally, the author proposes that Agnostids might have been parasites. The lecturer refutes this as well, as the large number of Agnostids fossils indicate a large population, unlike the limited population of parasites that feed on hosts.
In conclusion, there is a discrepancy between the views of the writer and the lecturer on the lifestyle of Agnostids. Further research is needed to clarify the matter.
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Transition Words or Phrases used:
but, finally, however, if, may, well, in conclusion, such as
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 10.0 10.4613686534 96% => OK
Auxiliary verbs: 2.0 5.04856512141 40% => OK
Conjunction : 8.0 7.30242825607 110% => OK
Relative clauses : 7.0 12.0772626932 58% => More relative clauses wanted.
Pronoun: 10.0 22.412803532 45% => OK
Preposition: 27.0 30.3222958057 89% => OK
Nominalization: 4.0 5.01324503311 80% => OK
Performance on vocabulary words:
No of characters: 1125.0 1373.03311258 82% => OK
No of words: 207.0 270.72406181 76% => More content wanted.
Chars per words: 5.4347826087 5.08290768461 107% => OK
Fourth root words length: 3.79308509922 4.04702891845 94% => OK
Word Length SD: 2.87042717092 2.5805825403 111% => OK
Unique words: 122.0 145.348785872 84% => More unique words wanted.
Unique words percentage: 0.589371980676 0.540411800872 109% => OK
syllable_count: 349.2 419.366225166 83% => OK
avg_syllables_per_word: 1.7 1.55342163355 109% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 0.0 3.25607064018 0% => OK
Article: 7.0 8.23620309051 85% => OK
Subordination: 3.0 1.25165562914 240% => Less adverbial clause wanted.
Conjunction: 2.0 1.51434878587 132% => OK
Preposition: 3.0 2.5761589404 116% => OK
Performance on sentences:
How many sentences: 10.0 13.0662251656 77% => 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: 20.0 21.2450331126 94% => OK
Sentence length SD: 40.694471369 49.2860985944 83% => OK
Chars per sentence: 112.5 110.228320801 102% => OK
Words per sentence: 20.7 21.698381199 95% => OK
Discourse Markers: 6.0 7.06452816374 85% => OK
Paragraphs: 5.0 4.09492273731 122% => OK
Language errors: 0.0 4.19205298013 0% => OK
Sentences with positive sentiment : 4.0 4.33554083885 92% => OK
Sentences with negative sentiment : 3.0 4.45695364238 67% => 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: 0.188057811538 0.272083759551 69% => OK
Sentence topic coherence: 0.0667592265889 0.0996497079465 67% => OK
Sentence topic coherence SD: 0.0470143464777 0.0662205650399 71% => OK
Paragraph topic coherence: 0.090670617738 0.162205337803 56% => OK
Paragraph topic coherence SD: 0.0483081952313 0.0443174109184 109% => OK
Essay readability:
automated_readability_index: 14.5 13.3589403974 109% => OK
flesch_reading_ease: 42.72 53.8541721854 79% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 12.3 11.0289183223 112% => OK
coleman_liau_index: 14.21 12.2367328918 116% => OK
dale_chall_readability_score: 10.04 8.42419426049 119% => OK
difficult_words: 71.0 63.6247240618 112% => OK
linsear_write_formula: 11.0 10.7273730684 103% => OK
gunning_fog: 10.0 10.498013245 95% => OK
text_standard: 11.0 11.2008830022 98% => OK
What are above readability scores?
---------------------
Rates: 86.6666666667 out of 100
Scores by essay e-grader: 26.0 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.