It is believed that the average size of a mammal species is a major factor in the period of gestation (the period of development in the uterus from conception until birth). In general, it is observed that the bigger the mammal is, the longer the gestation period. Table 1 gives adult mass in kilograms and gestation period in weeks of some species (source: https://www.saburchill.com/chapters/chap0037.html).
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Table 1
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Species
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Adult mass (kg)
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Gestation period (weeks)
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African elephant
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6000
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88
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Horse
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400
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48
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Grizzly bear
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400
|
30
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Lion
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200
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17
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Wolf
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34
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9
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Badger
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12
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8
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Rabbit
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2
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4.5
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Squirrel
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0.5
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3.5
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Table 2
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Species
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Gestation period (weeks)
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Indian elephant
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89.0
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Camel
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57.0
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Sea lion
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51.4
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Dog
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8.7
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Rat
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3.0
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Hamster
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2.3
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(a) Calculate the least-squares regression line for these data with adult mass as the independent variable.
(b) Plot the points and the least-squares regression line on the same graph.
(c) Calculate the least-squares regression line for these data with gestation period as the independent variable.
(d) Assuming that the regression model of part (c) holds for all mammals, estimate the adult mass in kilograms for the mammals given in Table 2.