Lee-Ann C. Hayek

Community attitudes toward three protected areas in Upper Myanmar (Burma)

SUMMARY An effective protected area system is essential for thelong-termconservationofMyanmar’sbiodiversity. This study examined the attitudes of 2915 residents in 97 communities around three protected areas (PAs) in upper Myanmar: Alaungdaw Kathapa National Park in the western mountains, Htamanthi Wildlife Sanctuary in the hills bordering the Chindwin and Uru rivers, and Chatthin Wildlife Sanctuary in the central dry zone. Logistic regression indicated a positive attitude toward the PAs was most highly correlated with a perception of conservation benefits and benefits resulting from management of the areas. Attitude was also significantly correlated with a perception of extraction benefits, conflicts with PA staff and crop damage by wildlife. Socioeconomic variables were less powerful than perceptions in predicting attitude and, unlike perceptions, their effectsvariedamongtheareas.Themuchgreatereffect of perceptions, especially positive ones, on people’s attitudes indicates that understanding perceptions is important to improving the relationship between local residents and these PAs. This finding underscores the fact that a focus on conflicts to understand people’s attitudes toward PAs may undervalue or miss critical positive perceptions that people hold. Understanding local residents’ perceptions of PAs makes possible the creation of strategic, place-based management strategies that build on people’s positive perceptions and mitigate their negative perceptions.

FORAMINIFERAL DENSITIES OVER FIVE YEARS IN THE INDIAN RIVER LAGOON, FLORIDA: A MODEL OF PULSATING PATCHES

Densities of 5 taxa along with 7 environmental variables were measured monthly with 4 replicates at each of 3 stations over a period of 5 years. The 720 observations of density for each taxon were analyzed by General Linear Models with density as the dependent variable. Differences among stations, years, seasons and their interactions are all significant. When treated as covariates environmental variables contributed little to explaining the observed variability in densities. However, the observed densities of the taxa are highly correlated and when a single taxon is treated as a covariate most of the variability in the density of a related taxon is explained. There are no significant differences among replicates (taken within a square meter) or their interactions. Consequently, the biotic or abiotic factor(s), although unknown, responsible for the simultaneous density variation of the taxa operate on a relatively small spatial scale. Based on these observations and previous studies, we propose a model wherein individual foraminifers are spatially distributed as a heterogeneous continuum forming patches with different densities that are only meters apart; reproduction is asynchronous causing pulsating patches that vary in space and time. Thus, we would expect significant differences among stations, years, seasons and their interaction. At the same time, no long-term increase or decrease in density for any of the taxa is observed. Evidently, long-term stability is achieved through considerable short-term variability in space and time. Although observations at a single station are not indicative of a larger area at any particular time, the concept of pulsating patches indicates that observations at a station will in the long-term give an assessment of a larger area.

Biodiversity resolution: an integrated approach

Fifty years of ecological research have failed to achieve an integrated, quantitative analysis suitable for both marine and terrestrial biodiversity. We present a new approach that reconciles the interrelationship of the number of individuals and species with population structure. Sample size dependency, always the primary obstacle, here is recognized as the primary missing requirement for biodiversity analysis. With this key, and a new decomposition formula, we solve the two historically intractable problems of (1) inability to separate species effects of richness and evenness within the same system, and (2) correlation of diversity measures and non- specificity of statistical distributions with sample size. In addition to providing resolution for ecological investigations, this approach reveals ordered structure in inventory and monitoring situations, undetectable by any other approach. As an example, Bolivian and Guyanan trees are shown to exhibit uniquely distinct and heretofore unseen diversity patterns.

Determination of sex with a discriminant analysis of new pelvic bone measurements: Part II.

The pelves of 100 white skeletons were measured on both sides for the following: (1) length from the superiormost aspect of the pubic symphysis to the nearest rim of the acetabulum (PS-A), (2) length from the highest point of the pubic tubercle to the nearest rim of the acetabulum (PT-A), (3) acetabular diameter (AD), (4) the vertical distance from the anterior aspect of the ischial tuberosity to the farthest rim of the acetabulum (IT-A), and (5) greatest femur head diameter. From these, three indices were derived: AD/PS-A (acetabulum/pubis index), AD/PT-A (acetabular diameter/pubic tubercle-acetabular rim index), and IT-A/PS-A (ischium-acetabulum height/pubic symphysis-acetabular rim index). The left AD/PS-A ratio and left IT-A height proved statistically to be of greatest discriminating value. Using these two variables, a discriminant function was derived which correctly separated 98% of our sample. The acetabulum/pubis ratio alone correctly assigned 95%. With either the discriminant function analysis of two variables or the acetabulum/pubis index as a single predictor, 97% of our sample of known sex was correctly identified if all specimens that fell within a doubtful or overlapping range of values were sorted by femur head diameter.

On richness and evenness within and between communities

Abstract Although there is extraordinary interest in the quantitative measurement of species diversity, published statements on the behavior of the components of species diversity are contradictory and lead to opposite conclusions. In this paper, we demonstrate that the confusion is due to two key oversights: (1) whether or not biological sampling is carried out within or between communities; and (2) determination of the statistical distribution underlying a biological community, which is crucial for the evaluation of all of the components of diversity measurement. The problem of sampling “within” a population or community is basically distinct from the equivalent integration of structure and diversity measurement “between” differing multispecies populations. “Within-community sampling” is defined as a set of biological samples from a statistical population that has a particular statistical distribution or a constant value for the associated parameter(s). As the number of individuals increases along with the number of species, for a log series distribution, the diversity measures of Shannons H, log series or Fishers α, and Simpsons Index 1/λ remain constant while the evenness measures of Buzas-Gibsons E and Pielous J decrease. For a log-normal distribution, J will remain constant while E decreases and α, 1/λ, and H increase. No single measure of evenness remains constant over all statistical distributions, so if constancy as a type of independence is required, the appropriate distribution must first be determined. Each species ensemble is mathematically fixed by the applicable statistical distribution. In contrast, “between-community sampling” is defined as a set of biological samples from different statistical distributions and/or the same distribution with differing parametric values. If sampling is between communities and S increases while the number of individuals remains constant, then all the other measures considered here increase. The exception is the broken stick, for which E remains constant while H, J, α, and 1/λ increase. Herein we propose and justify the use of the log-series distribution (with regression on the information decomposition equation) as a null model for determination of community structure and demonstrate that the community structure of a Miocene bed at Calvert Cliffs, Maryland, is a log series by use of this new unified methodology.

Quantitative genetics of bryozoan phenotypic evolution. I: Rate tests for random change versus selection in differentiation of living species

The possible roles of random genetic change and natural selection in bryozoan speciation were analyzed using quantitative genetic methods on breeding data for traits of skeletal morphology in two closely related species of the cheilostome Stylopoma. The hypothesis that morphologic differences between the species are caused entirely by mutation and genetic drift could not be rejected for reasonable rates of mutation maintained for as few as 103 to 104 generations. Divergence times this short or shorter are consistent with the abrupt appearances of many invertebrate species in the fossil record, commonly followed by millions of years of morphologic stasis. To produce these differences over 103 generations or fewer, directional selection acting alone would require unrealistically high levels of minimum selective mortality throughout divergence. Thus, selection is unnecessary to explain the divergence of these species, except as a means of accelerating the effects of random genetic change on shorter time scales (directional selection), or decelerating them over longer ones (stabilizing selection). These results are consistent with a variety of models of phenotypic evolution involving random shifts between multiple adaptive peaks. Similar results were obtained by substituting trait heritabilities and genetic covariances reconstructed by partitioning within‐ and among‐colony phenotypic variance in place of the values based on breeding data. Quantitative genetic analysis of speciation in fossil bryozoan lineages is thus justified.

QUANTITATIVE GENETICS OF BRYOZOAN PHENOTYPIC EVOLUTION. II. ANALYSIS OF SELECTION AND RANDOM CHANGE IN FOSSIL SPECIES USING RECONSTRUCTED GENETIC PARAMETERS

The roles of natural selection and random genetic change in the punctuated phenotypic evolution of eight Miocene‐Pliocene tropical American species of the cheilostome bryozoan Metrarabdotos are analyzed by quantitative genetic methods. Trait heritabilities and genetic covariances reconstructed by partitioning within‐ and among‐colony phenotypic variance are similar to those previously obtained for living species of the cheilostome Stylopoma using breeding data. The hypothesis that differences in skeletal morphology between species of Metrarabdotos are entirely due to mutation and genetic drift cannot be rejected for reasonable rates of mutation maintained for periods brief enough to account for the geologically abrupt appearances of these species in the fossil record. Except for one pair of species, separated by the largest morphologic distance, directional selection acting alone would require unrealistically high rates of selective mortality to be maintained for these periods. Thus, directional selection is not strongly implicated in the divergence of Metrarabdotos species. Within species, rates of net phenotypic change are slow enough to require stabilizing selection, but mask large, relatively rapid fluctuations, all of which, however, can be attributed to chance departures from the mean phenotype by mutation and genetic drift, rather than to tracking environmental fluctuation by directional selection. The results are consistent with genetic models involving shifts between multiple adaptive peaks on which phenotypes remain more or less static through long‐term stabilizing selection. Regardless of the degree to which directional selection may be involved in peak shifts, phenotypic differentiation is thus related to processes different than the pervasive stabilizing selection acting within species.

Extending the climatic precession curve back into the Late Miocene by signature template comparison

The rhythm of sedimentary cycles reflecting the climatic precession signal (19 and 23 kyr components) from the upper Miocene of the Bou Regreg section at Ain el Beida near Rabat, Morocco, had been analyzed to determine the age of the geomagnetic polarity reversals of Subchron 5N1 (C3An.1n). A new method of analysis of cycle “signatures” uses adjusted data series as represented by a signal obtained from grey-level traces through image-enhanced photographs of the sediment cycles. The measured, “timeless” signal is reduced and geometrically transformed to a signature template in order to compare its pattern with similar time constrained segments of the target precession signal (retrodicted for 35° N). Conventional statistical and spectral analysis tests are used to regress to the best possible fit. A date estimate of 5.94 Ma for the Chron 5/Gilbert boundary (C3An.1n/C3r), which occurs near the times of the closure of the Rifian Corridor and the beginning of the “drawdown” phase of the Messinian Salinity Crisis, is found to be in close agreement with independent approximations derived from extrapolation of sea floor spreading, radiometric dating, and younger Earth-orbital tuning ages.

Geometric consequences of branching growth in adeoniform bryozoa

-Many cheilostome bryozoans of diverse phylogenetic origin grow as erect, arborescent colonies with branches of modified planar form composed of two layers of zooids back to back. Regular branching enables a growing colony to expand in surface area, and hence in the number of zooids that feed, reproduce, and perform other vital functions, at an accelerating rate. During growth, branches first all diverge, then increasingly converge, and in late stages of growth begin to interfere with each others growth and function. Interference can set limits to the width and thickness of branches and hence to the number and size of zooids. Simulation of growth using a 3-dimensional mathematical model shows that a narrow range of possible values of branching angles minimizes branch interference in late growth stages. These values are prevalent in fossil and modern species. Branch spacing at later growth stages is correlated with the distance between branches at first crossing, providing room for feeding organs of the two facing layers of zooids to protrude and function. Interbranch distances dwindle as branches increasingly converge, so emphasis on minimizing interference at a late stage sets a practical limit to growth beyond that stage. To gain this long-term benefit requires adhering to a regular pattern throughout growth. The considerable variation in branching properties in fossil and modern species, and a variability in spacing inherent in the growth pattern itself, limit the amount of usable interbranch space. Despite a higher intraspecific variability, branching properties are as distinctive interspecifically as zooidal properties, and variability is randomly distributed through the colony. A small reduction in variability between fossil and modern species suggests that increasing regularity may provide a selective advantage in the utilization of interbranch space. Alan H. Cheetham. Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560 Lee-Ann C. Hayek. Scientific Applications Division, Office of Information Resources Management, Smithsonian Institution, Washington, D.C. 20560 Accepted: August 24, 1983

QUANTITATIVE GENETICS OF BRYOZOAN PHENOTYPIC EVOLUTION. III: PHENOTYPIC PLASTICITY AND THE MAINTENANCE OF GENETIC VARIATION

Cheilostome bryozoan species show long‐term morphologic stasis, implying stabilizing selection sustained for millions of years, but nevertheless retain significant heritable variation in traits of skeletal morphology. The possible role of within‐genotype (within‐colony) phenotypic variability in preserving genetic diversity was analyzed using breeding data for two species of Stylopoma from sites along 110 km of the Caribbean coast of Panama. Variation among zooids within colonies accounts for nearly two‐thirds of the phenotypic variance on average, increases with environmental heterogeneity, and includes significant genotype‐environment interaction. Thus, within‐colony variability apparently represents phenotypic plasticity, at least some of which is heritable, rather than random “developmental noise.” Almost all of the among‐colonies component of phenotypic variance is accounted for by additive genetic differences in trait means, suggesting that within‐colony plasticity includes virtually all of the environmental component of phenotypic variance in these populations of Stylopoma. Thus, heritable within‐colony plasticity could play a significant part in maintaining genetic diversity in cheilostomes, but it is also possible that rates of polygenic mutation alone are sufficient to balance the effects of selection.