TY - JOUR
T1 - Patterns of secondary sexual size dimorphism in new world myotis and a test of rensch's rule
AU - Stevens, Richard D.
AU - Platt, Roy N.
N1 - Publisher Copyright:
© 2015 American Society of Mammalogists.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - For bats, when secondary sexual dimorphism is significant, females typically are larger than males. Moreover, in mammals, variation in the degree of sexual dimorphism often follows an allometric relationship whereby differences vary with body size (Rensch's rule). We examined sexual dimorphism across the New World clade of Myotis regarding species-specific and clade-wide patterns of body, cranium, and wing size, Rensch's rule and degree to which such morphological variation is related to phylogeny. Size differences were common with significant cases of both male-biased and female-biased sexual dimorphism. In more than half the cases, females were larger than males. Variation in degree of dimorphism exhibited an allometric pattern. Nonetheless, slope of the relationship between size and degree of dimorphism was no different from unity (i.e., isometry), failing to support Rensch's rule. There was a strong and significant relationship between phylogeny and morphological variation but not between phylogeny and degree of dimorphism. Patterns suggest that differences between males and females enhance aerodynamic capabilities of females whereby larger mothers can overcome constraints on flight due to the mass of large fetuses and newborns.
AB - For bats, when secondary sexual dimorphism is significant, females typically are larger than males. Moreover, in mammals, variation in the degree of sexual dimorphism often follows an allometric relationship whereby differences vary with body size (Rensch's rule). We examined sexual dimorphism across the New World clade of Myotis regarding species-specific and clade-wide patterns of body, cranium, and wing size, Rensch's rule and degree to which such morphological variation is related to phylogeny. Size differences were common with significant cases of both male-biased and female-biased sexual dimorphism. In more than half the cases, females were larger than males. Variation in degree of dimorphism exhibited an allometric pattern. Nonetheless, slope of the relationship between size and degree of dimorphism was no different from unity (i.e., isometry), failing to support Rensch's rule. There was a strong and significant relationship between phylogeny and morphological variation but not between phylogeny and degree of dimorphism. Patterns suggest that differences between males and females enhance aerodynamic capabilities of females whereby larger mothers can overcome constraints on flight due to the mass of large fetuses and newborns.
KW - Myotis
KW - Rensch's rule
KW - bats
KW - morphometrics
KW - secondary sexual dimorphism
UR - http://www.scopus.com/inward/record.url?scp=84949995841&partnerID=8YFLogxK
U2 - 10.1093/jmammal/gyv120
DO - 10.1093/jmammal/gyv120
M3 - Article
AN - SCOPUS:84949995841
VL - 96
SP - 1128
EP - 1134
JO - Journal of Mammalogy
JF - Journal of Mammalogy
SN - 0022-2372
IS - 6
ER -