A review of techniques for quantifying sexual size dimorphism

Journal Article · · Growth Development and Aging; (United States)

OSTI ID:6433023

Lovich, J E; Gibbons, J W ^[1]

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1. Savannah River Ecology Lab., Aiken, SC (United States)

Previous studies of sexual size dimorphism (SSD) use a variety of size dimorphism indices (SDI's) to quantify SSD. We propose that a useful SDI should meet four criteria as follows; (1) it should be properly scaled, (2) it should have high intuitive value, (3) it should produce values with one sign, (positive) when sex A is larger than sex B, and the opposite sign when sex B is larger, and (4) it should produce values that are symmetric around a central value, preferably zero. Many previously published SDI's do not meet any of these criteria, and none meet more than three. We present an alternative SDI based on the mean size of the larger sex divided by the mean size of the smaller sex with the result arbitrarily defined as positive (minus one) when females are larger and negative (plus one) in the converse case. Careful selection of a primary size variable is crucial to meaningful interpretation of sexual size differences.

• OSTI ID: 6433023
• Journal Information: Growth Development and Aging; (United States), Journal Name: Growth Development and Aging; (United States) Vol. 56:4; ISSN 1041-1232; ISSN GDAGE9
• Country of Publication: United States
• Language: English

Related Subjects

550800* -- Morphology
59 BASIC BIOLOGICAL SCIENCES
BIOLOGICAL VARIABILITY
EQUATIONS
FEMALES
MALES
MATHEMATICS
PREDICTION EQUATIONS
SEX DEPENDENCE
SIZE
STATISTICS