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.
Question
Summarize the points made in the lecture, being sure to explain how they challenge the specific theories presented in the reading passage.
Both author and lecturer discuss whether Agnostids were swimming predators, seafloor dwellers, or parasites. The former argues in support of these whereas, the latter contradicts all of these points.
First of all, the passage states Agnostids must be free-swimming predators, as other types of primitive arthropods were good swimmers and better predators so, it is reasonable to say Agnostids also followed the same pattern similar to that of their ancestors. However, the listening rebuts if that was the case since other primitive arthropods had well-developed and more proficient eyes that allowed them to track prey whereas Agnostids had poorly-developed eyes and sometimes their eyes didn't even work. Furthermore, they didn't have other sensory organs to compensate for their lacking vision.
Second of all, the reading claims that Agnostids could have been seafloor dwellers on the basis of other primitive arthropods which lived this way so, the passage assumes the same for the Agnostids. On the other hand, the professor counters this statement as those arthropods didn't have the ability to move fast and always stayed in a localized area so, the claim of Agnostids being seafloor dwellers was inappropriate as they had the ability to move really fast and they often were found moving in the very large geographical area. In addition, they were also found living in multiple locations.
Finally, the text asserts Agnostids are parasites because most of today's arthropods exist as parasites, and they live and feed off the larger organisms. In contrast, the lecturer argues against this belief as parasites only existed in smaller numbers so, that the host can still be alive containing them, however, the vast amount of fossils of Agnostids implies that they existed in really large numbers which is not possible for the organisms surviving as a parasite.
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Grammar and spelling errors:
Line 3, column 490, Rule ID: EN_CONTRACTION_SPELLING
Message: Possible spelling mistake found
Suggestion: didn't
...developed eyes and sometimes their eyes didnt even work. Furthermore, they didnt have...
^^^^^
Line 3, column 525, Rule ID: EN_CONTRACTION_SPELLING
Message: Possible spelling mistake found
Suggestion: didn't
...eyes didnt even work. Furthermore, they didnt have other sensory organs to compensate...
^^^^^
Line 5, column 277, Rule ID: EN_CONTRACTION_SPELLING
Message: Possible spelling mistake found
Suggestion: didn't
...ters this statement as those arthropods didnt have the ability to move fast and alway...
^^^^^
Line 5, column 473, Rule ID: ADVERB_WORD_ORDER[5]
Message: The adverb 'often' is usually put after the verb 'were'.
Suggestion: were often
...he ability to move really fast and they often were found moving in the very large geograph...
^^^^^^^^^^
Line 7, column 59, Rule ID: MOST_SOME_OF_NNS[1]
Message: After 'most of', you should use 'the' ('most of the todays') or simply say ''most todays''.
Suggestion: most of the todays; most todays
...asserts Agnostids are parasites because most of todays arthropods exist as parasites, and they...
^^^^^^^^^^^^^^
Transition Words or Phrases used:
also, but, finally, first, furthermore, however, if, really, second, so, still, well, whereas, in addition, in contrast, first of all, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 13.0 10.4613686534 124% => OK
Auxiliary verbs: 3.0 5.04856512141 59% => OK
Conjunction : 9.0 7.30242825607 123% => OK
Relative clauses : 8.0 12.0772626932 66% => More relative clauses wanted.
Pronoun: 24.0 22.412803532 107% => OK
Preposition: 30.0 30.3222958057 99% => OK
Nominalization: 2.0 5.01324503311 40% => More nominalizations (nouns with a suffix like: tion ment ence ance) wanted.
Performance on vocabulary words:
No of characters: 1578.0 1373.03311258 115% => OK
No of words: 296.0 270.72406181 109% => OK
Chars per words: 5.33108108108 5.08290768461 105% => OK
Fourth root words length: 4.14784890444 4.04702891845 102% => OK
Word Length SD: 2.72067504138 2.5805825403 105% => OK
Unique words: 166.0 145.348785872 114% => OK
Unique words percentage: 0.560810810811 0.540411800872 104% => OK
syllable_count: 481.5 419.366225166 115% => 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: 11.0 8.23620309051 134% => OK
Subordination: 1.0 1.25165562914 80% => OK
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: 29.0 21.2450331126 137% => The Avg. Sentence Length is relatively long.
Sentence length SD: 93.9103828126 49.2860985944 191% => OK
Chars per sentence: 157.8 110.228320801 143% => OK
Words per sentence: 29.6 21.698381199 136% => OK
Discourse Markers: 15.2 7.06452816374 215% => Less transition words/phrases wanted.
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 5.0 4.19205298013 119% => OK
Sentences with positive sentiment : 3.0 4.33554083885 69% => 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: 0.211606960435 0.272083759551 78% => OK
Sentence topic coherence: 0.0835623563098 0.0996497079465 84% => OK
Sentence topic coherence SD: 0.0508765816327 0.0662205650399 77% => OK
Paragraph topic coherence: 0.122666271223 0.162205337803 76% => OK
Paragraph topic coherence SD: 0.0244505592155 0.0443174109184 55% => OK
Essay readability:
automated_readability_index: 18.5 13.3589403974 138% => OK
flesch_reading_ease: 42.04 53.8541721854 78% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 14.6 11.0289183223 132% => OK
coleman_liau_index: 14.23 12.2367328918 116% => OK
dale_chall_readability_score: 9.29 8.42419426049 110% => OK
difficult_words: 79.0 63.6247240618 124% => OK
linsear_write_formula: 14.0 10.7273730684 131% => OK
gunning_fog: 13.6 10.498013245 130% => OK
text_standard: 14.0 11.2008830022 125% => OK
What are above readability scores?
---------------------
Rates: 80.0 out of 100
Scores by essay e-grader: 24.0 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.