Phylogenetic Analysis of Covariance by Computer Simulation

Garland, Theodore; Dickerman, Allan W.; Janis, Christine M.; Jones, Jason A.

doi:10.2307/2992464

Cited by 619 publications

(1,004 citation statements)

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“…0. To compute independent contrasts, we used the PDAP :PDTREE module (Garland et al 1993 ;Midford et al 2005) implemented in Mesquite Modular System for Evolutionary Analysis . Procedures for the analyses followed Garland et al (1992Garland et al ( , 1993 and Pagel (1992).…”

Section: A T E R I a L S A N D M E T H O D Smentioning

confidence: 99%

Resource predictability and host specificity in fleas: the effect of host body mass

et al. 2006

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Ecological specialization is hypothesized to result from the exploitation of predictable resource bases. For parasitic organisms, one prediction is that parasites of large-bodied host species, which tend to be long-lived, should specialize on these hosts, whereas parasites of small host species, which represent more ephemeral and less predictable resources, should become generalists. We tested this prediction by quantifying the association between the level of host specificity of fleas and the mean body mass of their mammalian hosts, using published data from 2 large, distinct geographical regions (South Africa and northern North America). In general, we found supporting evidence that flea host specificity, measured either as the number of host species exploited or their taxonomic distinctness, became more pronounced with increasing host body mass. There were, however, some discrepancies among the results depending on the different measures of host specificity, the geographical region studied, or whether we used the raw values or phylogenetically independent contrasts. These are discussed with respect to other forces acting on the evolution of host specificity in parasites, as well as in the context of the regions' contrasting evolutionary histories. Overall, though, our findings indicate that the exploitation of large-bodied, and therefore long-lived, host species has promoted specialization in fleas, most likely because these hosts represent predictable resources.

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Section: A T E R I a L S A N D M E T H O D Smentioning

confidence: 99%

Resource predictability and host specificity in fleas: the effect of host body mass

et al. 2006

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“…The significance of these suborder differences was first tested using nonparametric Mann-Whitney U-tests, considered significant at P Յ 0.05. However, traditional statistical methods for the analysis of comparative data fail to take into account the nonindependence of species/ genus means due to phylogenetic relatedness (Felsenstein, 1985), resulting in inflated type I error rates and lowered statistical power (Garland et al, 1993). Methods are now available for the incorporation of patterns of phylogenetic relationship into statistical calculations of ANOVA, ANCOVA, correlation, and regression.…”

Section: Analysesmentioning

confidence: 99%

“…Methods are now available for the incorporation of patterns of phylogenetic relationship into statistical calculations of ANOVA, ANCOVA, correlation, and regression. These techniques are applied here using PDAP (Phenotypic Diversity Analysis Programs, version 6, 2002) (Garland et al, 1993) and the results are compared with those obtained using traditional parametric and nonparametric methods.…”

Section: Analysesmentioning

confidence: 99%

Primate auditory diversity and its influence on hearing performance

2004

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The auditory region contains numerous structures that have proven useful for phylogenetic classification at various taxonomic levels. However, little work has been done in primates relating differences in morphology to variations in hearing performance. This study documents anatomical and physiological distinctions within primates and begins to address the functional and evolutionary consequences of these and other auditory features. The dimensions of the outer ear (pinna) were measured in cadaveric specimens representing nearly every primate family and used to calculate a shape ratio (height/width). It was found that nonanthropoids have a significantly higher ratio than anthropoids, although the actual height was not found to differ. This indicates that most nonanthropoids have ears that are tall and narrow, whereas monkeys and apes are characterized by ears with more equal height and width dimensions. Eardrum area, stapedial footplate area, and ossicular lever arm lengths were measured in dried specimens to calculate an impedance transformer ratio. A distinction was found between anthropoids and strepsirrhines, with the latter group having a transformer ratio indicative of a higher percentage of acoustic energy transmission through the middle ear. Audiogram data were gathered from the literature to analyze hearing sensitivity and it was found that platyrrhines illustrate more low-frequency sensitivity than like-sized lorisoids. The effects of intraspecific variation on the audiogram results were also examined and were found to produce similar results as the analysis using species mean threshold values. Lastly, correlations between morphological and audiogram variables were examined. Several measures of hearing sensitivity were found to be correlated with pinna shape but correlations with middle ear transmission properties were weaker. In addition to using traditional statistical techniques, phylogenetic corrective methods were applied to address the problem of statistical nonindependence of the data and the results of both analyses are compared. These findings are discussed with respect to how sensory adaptations and phylogenetic history may be related to the current radiation of primates. Key words: primate hearing; outer ears; middle ears; audiogram; phylogenyPrimates express numerous modifications on the fundamental mammalian middle ear morphology and these differences have proven useful for phylogenetic classification at various taxonomic levels (MacPhee and Cartmill, 1986). Among extant strepsirrhines, most Malagasy primates are characterized by a free-floating tympanic ring surrounded by a single relatively large tympanic cavity while lorisoids have a tympanic ring that is fused to the lateral wall of a smaller tympanic cavity. Lorises appear to maintain a substantial effective cavity volume by having additional pneumatic spaces off of the epitympanic recess. Extant haplorhines are similar to lorises in possessing epitympanic sinuses (except tarsiers) (MacPhee and Cartmill, 1986) and a fused tym...

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“…Four main sources were consulted for values of MLSP; Staav (1998) A phylogenetic supertree of all the bird species was created in PDTREE (Garland et al 1993) based mainly on the avian phylogeny of Sibley and Ahlquist (1990). A phylogenetic tree consists of branches, nodes and tips (or end nodes).…”

Section: Methodsmentioning

confidence: 99%

“…The number of un-standardised contrasts is one less than the total number of tips in the tree; standard contrasts (SC) are calculated by dividing each unstandardised contrast by its standard deviation. Hence SC can be regarded as independent values and used in standard statistical procedures (Garland et al 1993). Phylogenetic independent contrast (PIC) analysis was conducted using the Phenotypic Diversity Analysis Program (PDAP) (Garland et al 1993).…”

Section: Methodsmentioning

confidence: 99%

Energetics and longevity in birds

Furness

Speakman

2008

AGE

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The links between energy expenditure and ageing are different at different levels of enquiry. When studies have examined the relationships between different species within a given class the association is generally negative-animals with greater metabolism per gram of tissue live shorter lives. Within species, or between classes (e.g. between birds and mammals) the association is the opposite-animals with higher metabolic rates live longer. We have previously shown in mammals that the negative association between lifespan and metabolic rate is in fact an artefact of using resting rather than daily energy expenditure, and of failing to adequately take into account the confounding effects of body size and the lack of phylogenetic independence of species data. When these factors are accounted for, across species of mammals, the ones with higher metabolism also have the largest lifetime expenditures of energy-consistent with the inter-class and intra-specific data. A previous analysis in birds did not yield the same pattern, but this may have been due to a lack of sufficient power in the analysis. Here we present an analysis of a much enlarged data set (>300 species) for metabolic and longevity traits in birds. These data show very similar patterns to those in mammals. Larger individuals have longer lives and lower per-gram resting and daily energy expenditures, hence there is a strong negative relationship between longevity and mass-specific metabolism. This relationship disappears when the confounding effects of body mass and phylogeny are accounted for. Across species of birds, lifetime expenditure of energy per gram of tissue based on both daily and resting energy expenditure is positively related to metabolic intensity, mirroring these statistical relationships in mammals and synergising with the positive associations of metabolism with lifespan within species and between vertebrate classes.

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Phylogenetic Analysis of Covariance by Computer Simulation

Cited by 619 publications

References 0 publications

Resource predictability and host specificity in fleas: the effect of host body mass

Resource predictability and host specificity in fleas: the effect of host body mass

Primate auditory diversity and its influence on hearing performance

Energetics and longevity in birds

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