"A recent study of eighteen rhesus monkeys provides clues as to the effects of birth order on an individual's levels of stimulation. The study showed that in stimulating situations (such as an encounter with an unfamiliar monkey), firstborn infant monkeys produce up to twice as much of the hormone cortisol, which primes the body for increased activity levels, as do their younger siblings. Firstborn humans also produce relatively high levels of cortisol in stimulating situations (such as the return of a parent after an absence). The study also found that during pregnancy, first-time mother monkeys had higher levels of cortisol than did those who had had several offspring."
In the letter, the author exhibits a recent study of eighteen rhesus monkeys, indicating that there is a close link between the birth order of rhesus monkeys and the cortisol levels, and in view of this cue, so does with the human beings. Perhaps, this connection is true for rhesus monkey, but there are more factors may lead to the heightened levels of cortisol for this kind of primate animals, not to mention the humans. Based on the premise of the valid study, other explanations like interior emotion and diverse response of babies of different ages to exterior stimulus may illustrate the high levels of cortisol the firstborn shows in the stimulating situations, not just connecting with the birth order.
The close connection between the birth order on an individual's levels of stimulation may be explained by the genetic gene, coming from their mother, whose levels of cortisol is highly related to their offspring. For one thing, as the first baby, he may inherit more similar physiological characteristics from his mothers than his younger siblings. For example, the more active his mother's adrenal gland, the higher her first-born baby's cortisol level inherited, the less her second and next ones have this character. Another possibility is age, which decides the quantity of cortisol in a mother's body——the older a mother, the less her adrenal gland secretes cortisol, resulting in the younger babies with the less levels of cortisol, a quality inherited from his mother. So does with his inheritance from his father. Moreover, when a mother monkey is first pregnant, her level of cortisol is her first baby's, far higher than her next ones. For this reason, the level of cortisol of the firstborn baby may be in the genes.
Apart from the above-mentioned internal factors, the levels of cortisol lie in different responses that primate animals at different ages are confronted with outside environment. Generally speaking, due to better cognition and more experience, the older distinguishes between threat and safety more acutely than the younger, the latter easier credulous of strangers. Consider in the face of threatening situations, the firstborn monkey will quickly realize and respond to the dangerous situations, resulting in secreting more cortisol, compared with his younger siblings, to prepare for taking an aggressive or protective actions, aiming to ensure the safety of his own and his younger siblings, while the latter are even unconscious of the impending danger. Furthermore, when, with the increasing age, the elder autonomously burdens more responsibilities on his shoulders like taking care about his younger siblings, the increasing pressures will spur the secretion of cortisol, correspondingly the elder higher levels of cortisol than their younger sisters and brothers. The age differences therefore may also be one reason for the explanation of the high levels of cortisol in the firstborn babies.
Importantly, not only are the cues from the study applied to all the firstborn monkeys, but to the firstborn human beings, who also produce relatively high levels of cortisol in stimulating situations. Admittedly, this may be real, whereas the level of cortisol may depend on various causes, such as psychological and physiological changes. Conscious of the risk of parturition, the psychology of first-time mothers' is usually filled with terror and timidity, which in turn stimulate the secretion of cortisol, passing to her offspring, while at the next parturition, the nervous psychology will disappear, and accordingly the level of cortisol declines. For another, the physiological changes like bones, tissues, are often extremely apparent from the start of the first pregnancy, and then remain stable in next pregnancies and parturitions, inducing to the corresponding change of cortisol secretion and so does with their offspring from the first to the next, far from the effect of the birth order.
In a nutshell, although the cues that the level of cortisol is related to the birth order in stimulating situations may be true, there are many other explanations for the high levels of cortisol in the firstborn babies of primate animals: genes, maturity, psychological and physiological changes, and so on.
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...firstborn baby may be in the genes. Apart from the above-mentioned internal ...
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...from the effect of the birth order. In a nutshell, although the cues that th...
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Transition Words or Phrases used:
accordingly, also, but, first, furthermore, if, may, moreover, second, so, then, therefore, whereas, while, apart from, for example, kind of, such as, for one thing
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 19.0 19.6327345309 97% => OK
Auxiliary verbs: 12.0 12.9520958084 93% => OK
Conjunction : 20.0 11.1786427146 179% => OK
Relative clauses : 8.0 13.6137724551 59% => More relative clauses wanted.
Pronoun: 32.0 28.8173652695 111% => OK
Preposition: 103.0 55.5748502994 185% => OK
Nominalization: 15.0 16.3942115768 91% => OK
Performance on vocabulary words:
No of characters: 3601.0 2260.96107784 159% => OK
No of words: 673.0 441.139720559 153% => Less content wanted.
Chars per words: 5.35066864785 5.12650576532 104% => OK
Fourth root words length: 5.09335287823 4.56307096286 112% => OK
Word Length SD: 2.93684757641 2.78398813304 105% => OK
Unique words: 294.0 204.123752495 144% => OK
Unique words percentage: 0.436849925706 0.468620217663 93% => More unique words wanted or less content wanted.
syllable_count: 1106.1 705.55239521 157% => OK
avg_syllables_per_word: 1.6 1.59920159681 100% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 4.96107784431 81% => OK
Interrogative: 2.0 0.471057884232 425% => OK
Article: 18.0 8.76447105788 205% => Less articles wanted as sentence beginning.
Subordination: 5.0 2.70958083832 185% => OK
Conjunction: 6.0 1.67365269461 358% => Less conjunction wanted as sentence beginning.
Preposition: 5.0 4.22255489022 118% => OK
Performance on sentences:
How many sentences: 20.0 19.7664670659 101% => OK
Sentence length: 33.0 22.8473053892 144% => The Avg. Sentence Length is relatively long.
Sentence length SD: 90.7078276666 57.8364921388 157% => OK
Chars per sentence: 180.05 119.503703932 151% => OK
Words per sentence: 33.65 23.324526521 144% => OK
Discourse Markers: 8.2 5.70786347227 144% => OK
Paragraphs: 5.0 5.15768463074 97% => OK
Language errors: 5.0 5.25449101796 95% => OK
Sentences with positive sentiment : 8.0 8.20758483034 97% => OK
Sentences with negative sentiment : 3.0 6.88822355289 44% => More negative sentences wanted.
Sentences with neutral sentiment: 9.0 4.67664670659 192% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.165352568322 0.218282227539 76% => OK
Sentence topic coherence: 0.0615364467379 0.0743258471296 83% => OK
Sentence topic coherence SD: 0.0515905806741 0.0701772020484 74% => OK
Paragraph topic coherence: 0.113309265319 0.128457276422 88% => OK
Paragraph topic coherence SD: 0.0505168490681 0.0628817314937 80% => OK
Essay readability:
automated_readability_index: 20.6 14.3799401198 143% => OK
flesch_reading_ease: 37.98 48.3550499002 79% => OK
smog_index: 11.2 7.1628742515 156% => OK
flesch_kincaid_grade: 16.2 12.197005988 133% => OK
coleman_liau_index: 14.34 12.5979740519 114% => OK
dale_chall_readability_score: 9.47 8.32208582834 114% => OK
difficult_words: 179.0 98.500998004 182% => OK
linsear_write_formula: 17.5 12.3882235529 141% => OK
gunning_fog: 15.2 11.1389221557 136% => OK
text_standard: 21.0 11.9071856287 176% => OK
What are above readability scores?
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Write the essay in 30 minutes.
Rates: 66.67 out of 100
Scores by essay e-grader: 4.0 Out of 6 -- The score is based on the average performance of 20,000 argument essays. This e-grader is not smart enough to check on arguments.
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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.