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. Advances in the study of mammalian behavior. Mammals. Structure, Development, and Function 9 450g I200g lOkg \^%(,jf Muscle Brain. 6 7 8 Log body weight Heart Fig. 2. Growth rates of tissues (muscle, brain, heart) in relation to body weight in g. to the next. The head constitutes about 25% of birth weight, but drops to 6 or 7% of weight in the adult (Figs. 5 and 6). Three changes in the composition of the head are of great interest. First, the brain achieves full growth by 1,000 g body weight. Sec- ond, the eyes reach mature size at about 3 kg body weight. Third, at birth the mandible and ma
. Advances in the study of mammalian behavior. Mammals. Structure, Development, and Function 9 450g I200g lOkg \^%(,jf Muscle Brain. 6 7 8 Log body weight Heart Fig. 2. Growth rates of tissues (muscle, brain, heart) in relation to body weight in g. to the next. The head constitutes about 25% of birth weight, but drops to 6 or 7% of weight in the adult (Figs. 5 and 6). Three changes in the composition of the head are of great interest. First, the brain achieves full growth by 1,000 g body weight. Sec- ond, the eyes reach mature size at about 3 kg body weight. Third, at birth the mandible and masticatory muscles are absolutely smaller than the other tissue complexes. However, as the animal becomes nutritionally independent, as the teeth grow, and as the mandible is subjected to the compressive strains of chewing, the masticatory muscles grow at an accelerated rate (see Fig. 7). Ultimately, of course, muscle grows more in mass than bone. A dimorphism in the musculature is also evident—the percentage of the head that is muscle is twice as great in the adult male as in the adult female. Sexual dimorphism in the mass of the head results from these. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Eisenberg, John Frederick; Kleiman, Devra G; American Society of Mammalogists. [Shippensburg, Pa?] : American Society of Mammalogists
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Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjectmammals