Body Length mm

FIGURE 3.10 Mean egg size per individual increases significantly with body size among species of gonodactylid (open circles) and protosquillid (closed square) reef stomatopods (r2 = 0.12, F = 9.45, P = 0.003, y = 0.002x + 0.71).

restricted distributions in reef stomatopods. The latter indicates that most reef stomatopods risk extinction if faced with rapid global environmental changes.

Life history patterns of stomatopods are consistent with those found in other living and fossil groups for reproductive and life history traits, patterns of abundance, and frequency distributions of body size and geographic range. Body size is positively correlated with fecundity and colonizing ability in most marine invertebrates (Reaka, 1979, 1980; Strathmann and Strathmann, 1982; Jablonski and Lutz, 1983; Strathmann, 1985, 1990; Jablonski, 1986b, 1996; Reaka-Kudla, 1991; Roy et al., 2001, 2002; Jablonski

FIGURE 3.11 The percentage saturation of available reef habitat within each species' geographic range increases significantly with median body size among species of gonodactylid and protosquillid stomatopods (r2 = 0.54, F = 47.68, P < 0.001, y = 0.19x - 3.83). The percentage saturation of each species' range is the proportion of all 5 x 5° latitudinal and longitudinal quadrants containing habitable reef that is occupied by that species.

20 40 60 80 100 Body Length (mm)

FIGURE 3.11 The percentage saturation of available reef habitat within each species' geographic range increases significantly with median body size among species of gonodactylid and protosquillid stomatopods (r2 = 0.54, F = 47.68, P < 0.001, y = 0.19x - 3.83). The percentage saturation of each species' range is the proportion of all 5 x 5° latitudinal and longitudinal quadrants containing habitable reef that is occupied by that species.

Maximum Body Size Classes (mm)

FIGURE 3.12 Size frequency distributions of maximum body sizes for total species, regional endemics, and nonendemic species of reef stomatopods. Endemics are significantly smaller than nonendemics (t = 6.40, df = 146, P < 0.001; two-sample t test assuming unequal variance). Analysis of median body size for each species gives a similar graphical and statistical result.

et al., 2003a). Stomatopods share the following characteristics with taxa in both marine and terrestrial environments. (i) Body size frequency distributions are usually shifted toward small size classes (May, 1978, 1986, 1988; Rosenzweig, 1995; Gaston and Blackburn, 2000; Roy et al, 2000, 2002). (ii) Species abundances are biased toward few common and many rare species (Hubbell, 2001). (iii) Local abundance increases with range size (Gaston, 1994). (iv) Geographic range size increases with body size

58 / Marjorie L. Reaka, Paula J. Rodgers, and Alexei U. Kudla

•g 0 —i—i—i—i—i—i—i—i—i— 3 5 1015 20 25 30 35 40 45 50 55 60 65 70

Size of Geographic Range (No. of 5x5° Lat. x Long. Quadrats)

FIGURE 3.13 Size frequency distribution of geographic ranges in reef stomato-pods (Lat, latitude; Long, longitude). Other measures of geographic range size [latitudinal distance, longitudinal distance, square root of (latitude x longitude)2] yield a similar plot.

(Gaston and Blackburn, 1996). (v) Frequency distributions for geographic ranges are shifted toward small ranges [Gaston (1994, 1998), Gaston and Chown (1999), and Roberts and Hawkins (1999), but see Hughes et al. (2002)]. Commonalities in patterns of body size, life history, and distribution between reef stomatopods and other taxa suggest that the relationship between life history mechanisms and patterns of diversity and endemism we find in benthic reef organisms also may operate in other systems.

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