scholarly journals Can unified theories of biodiversity explain mammalian macroecological patterns?

2011 ◽  
Vol 366 (1577) ◽  
pp. 2554-2563 ◽  
Author(s):  
Kate E. Jones ◽  
Tim M. Blackburn ◽  
Nick J. B. Isaac
Keyword(s):  
Allometric Scaling ◽  
Species Traits ◽  
Theoretical Framework ◽  
Individual Species ◽  
Wild Mammal ◽  
Biodiversity Patterns ◽  
Scaling Relationships ◽  
Rigorous Testing ◽  
Unified Theories ◽  
Geographical Space

The idea of a unifying theory of biodiversity linking the diverse array of macroecological patterns into a common theoretical framework is very appealing. We explore this idea to examine currently proposed unified theories of biodiversity (UTBs) and their predictions. Synthesizing the literature on the macroecological patterns of mammals, we critically evaluate the evidence to support these theories. We find general qualitative support for the UTBs' predictions within mammals, but rigorous testing is hampered by the types of data typically collected in studies of mammals. In particular, abundance is rarely estimated for entire mammalian communities or of individual species in multiple locations, reflecting the logistical challenges of studying wild mammal populations. By contrast, there are numerous macroecological patterns (especially allometric scaling relationships) that are extremely well characterized for mammals, but which fall outside the scope of current UTBs. We consider how these theories might be extended to explain mammalian biodiversity patterns more generally. Specifically, we suggest that UTBs need to incorporate the dimensions of geographical space, species' traits and time to reconcile theory with pattern.

Comparison of mayfly (Ephemeroptera) taxocenes of permanent and intermittent Central European small streams via species traits

Biologia ◽  
2010 ◽  
Vol 65 (4) ◽  
Author(s):  
Pavla Řezníčková ◽  
Tomáš Soldán ◽  
Petr Pařil ◽  
Světlana Zahrádková
Keyword(s):  
Global Climate ◽  
Extreme Temperature ◽  
Oxygen Demand ◽  
Hydrological Regime ◽  
Species Traits ◽  
Individual Species ◽  
Biological Traits ◽  
Small Streams ◽  
High Oxygen Demand ◽  
The Impact

AbstractThe recurrent drying out of small streams in past decades has shown an urgent need to pay attention to the impact of global climate change. The objectives of this study were to describe the effect of drying out on the composition of the mayfly taxocene and evaluate the relevance of individual species traits for survival of mayflies to drying out. The mayfly taxocenes of two model localities, one at an intermittent and one at a permanent brook, were investigated in 2002, 2003 and 2005. Compared with the permanent stream, the taxocene of the intermittent stream was short of nine species, foremost rheobionts and high oxygen demand species. To explain further differences between both stream types in survival and recolonisation ability, 15 species traits were evaluated. These included so-called “ecological traits” (e.g., habitat and substrate range, density, distribution, current velocity adaptation) and “biological traits” connected with life cycle and larval/adult adaptations. Species showing the highest number of advantageous traits (with only exception of Electrogena sp. cf. ujhelyii — species of taxonomically unclear status) were able to successfully survive under the unfavourable conditions of the intermittent brook. Biological traits considered more important in many respects seem to be good predictors for assessing sensitivity to extreme temperature changes, hydrological regime fluctuations and the survival/recolonisation ability of species in exposed habitats.

scholarly journals Species traits and the form of individual species–energy relationships

2006 ◽  
Vol 273 (1595) ◽  
pp. 1779-1787 ◽  
Author(s):  
Karl L Evans ◽  
Sarah F Jackson ◽  
Jeremy J.D Greenwood ◽  
Kevin J Gaston
Keyword(s):  
Species Traits ◽  
Individual Species ◽  
Energy Relationships

scholarly journals LUGAR TURÍSTICO E TERRITÓRIO USADO: contribuições teóricas ao estudo do Turismo a partir da Geografia de Milton Santos

2019 ◽  
Vol 4 (15) ◽  
pp. 197
Author(s):  
José Alexandre Berto de Almada
Keyword(s):  
Theoretical Framework ◽  
Geographic Analysis ◽  
Geographic Space ◽  
Guiding Principle ◽  
Analytical Category ◽  
Geographical Space

TOURIST PLACE AND USED TERRITORY: theoretical contributions of the Tourism study from the Geography of Milton SantosLUGAR TURÍSTICO Y TERRITORIO USADO: contribuciones teóricas al estudio del Turismo a partir de la Geografía de Milton SantosRESUMOA Geografia do turismo não constitui em si mesma uma nova ciência geográfica, mas sim, uma forma de abordar o turismo pelo viés geográfico. O objetivo deste ensaio é apresentar uma proposta de abordagem do fenômeno do turismo a partir da Geografia Nova, de Milton Santos, utilizando seu arcabouço teórico para apreender o processo de produção do espaço geográfico pelo turismo, acrescentando ao diálogo outros autores e perspectivas e incluindo ao debate o conceito de Lugar Turístico como ferramenta para identificar o turismo no espaço geográfico e a categoria analítica do território usado como meio para operacionalizar a geografia miltoniana na apreensão do turismo no lugar. Na primeira parte deste ensaio discutimos o conceito de espaço geográfico e suas características ontológicas dentro da perspectiva da geografia de Milton Santos, sublinhando a categoria analítica do território usado. Na segunda parte incluímos o conceito de lugar turístico como fio condutor na identificação do turismo pela geografia. Na última parte apontamos elementos metodológicos para a realização de estudos sobre o turismo no espaço geográfico dentro da perspectiva apresentada neste ensaio. O lugar turístico é o conceito geográfico que permite identificar a materialização do turismo no espaço geográfico e o território usado a categoria analítica que permite apreender turismo no espaço. A análise geográfica do turismo deve levar em consideração as relações contraditórias entre os agentes que atuam na produção do lugar turístico que desvelam uma realidade complexa nos territórios onde há sua presença.Palavras-chave: Turismo; Território Usado; Lugar Turístico.ABSTRACTThe geography of tourism is not in itself a new geographical science, but rather a way of approaching tourism by geography. The objective of this paper is to present a proposal to approach the phenomenon of tourism from the Geografia Nova, by Milton Santos, using its theoretical framework to apprehend the process of production of geographical space by tourism, adding to the dialogue other authors and perspectives and including to the debate the concept of Tourist Place as a tool to identify tourism in the geographical space and the analytical category of the territory used as a means to operationalize the Miltonian geography in the apprehension of tourism in the place. In the first part of this paper we discuss the concept of geographic space and its ontological characteristics within the perspective of Milton Santos's geography, underlining the analytical category of the territory used. In the second part we include the concept of tourist place as a guiding principle in the identification of tourism by geography. In the last part we point out methodological elements for the study about tourism in the geographic space within the perspective presented in this paper. The tourist place is the geographical concept that allows to identify the materialization of the tourism in the geographical space and the territory used the analytical category that allows to seize tourism in the space. The geographic analysis of tourism must take into account the contradictory relations between the agents that act in the production of the tourist place that reveal a complex reality in the territories where it is present.Keywords: Tourism; Territory Used; Touristic Place.RESUMENLa geografía del turismo no constituye en sí misma una nueva ciencia geográfica, sino una forma de abordar el turismo por la geografía. El objetivo de este ensayo es presentar una propuesta de abordaje del fenómeno del turismo a partir de la Geografía Nova, de Milton Santos, utilizando su marco teórico para aprehender el proceso de producción del espacio geográfico por el turismo, añadiendo al diálogo otros autores y perspectivas e incluyendo al debate el concepto de Lugar Turístico como herramienta para identificar el turismo en el espacio geográfico y la categoría analítica del territorio usado como medio para operacionalizar la geografía miltoniana en la aprehensión del turismo en el lugar. En la primera parte de este ensayo discutimos el concepto de espacio geográfico y sus características ontológicas dentro de la perspectiva de la geografía de Milton Santos, subrayando la categoría analítica del territorio usado. En la segunda parte incluimos el concepto de lugar turístico como hilo conductor en la identificación del turismo por la geografía. En la última parte apuntamos elementos metodológicos para la realización de estudios sobre el turismo en el espacio geográfico dentro de la perspectiva presentada en este ensayo. El lugar turístico es el concepto geográfico que permite identificar la materialización del turismo en el espacio geográfico y el territorio usado a la categoría analítica que permite aprehender el turismo en el espacio. El análisis geográfico del turismo debe tener en cuenta las relaciones contradictorias entre los agentes que actúan en la producción del lugar turístico que desvelan una realidad compleja en los territorios donde hay su presencia.Palabras clave: Turismo; Territorio Usado; Lugar Turístico.

scholarly journals Allometric scaling relationships of jumping performance in the striped marsh frog Limnodynastes peronii

2000 ◽  
Vol 203 (12) ◽  
pp. 1937-1946 ◽  
Author(s):  
R.S. Wilson ◽  
C.E. Franklin ◽  
R.S. James
Keyword(s):  
Body Mass ◽  
Contact Time ◽  
Allometric Scaling ◽  
Size Range ◽  
Force Platform ◽  
Marsh Frog ◽  
Jumping Performance ◽  
Scaling Relationships ◽  
Jump Distance ◽  
Mass Exponents

We constructed a force platform to investigate the scaling relationships of the detailed dynamics of jumping performance in striped marsh frogs (Limnodynastes peronii). Data were used to test between two alternative models that describe the scaling of anuran jumping performance; Hill's model, which predicts mass- independence of jump distance, and Marsh's model, which predicts that jump distance increases as M(0.2), where M is body mass. From the force platform, scaling relationships were calculated for maximum jumping force (F(max)), acceleration, take-off velocity (U(max)), mass-specific jumping power (P(max)), total jumping distance (D(J)) and total contact time for 75 L. peronii weighing between 2.9 and 38. 4 g. F(max) was positively correlated with body mass and was described by the equation F(max)=0.16M(0.61), while P(max) decreased significantly with body mass and was described by the equation P(max)=347M(−)(0.46). Both D(J) and U(max) were mass-independent over the post-metamorph size range, and thus more closely resembled Hill's model for the scaling of locomotion. We also examined the scaling relationships of jumping performance in metamorph L. peronii by recording the maximum jump distance of 39 animals weighing between 0.19 and 0.58 g. In contrast to the post-metamorphic L. peronii, D(J) and U(max) were highly dependent on body mass in metamorphs and were described by the equations D(J)=38M(0.53) and U(max)=1.82M(0.23), respectively. Neither model for the scaling of anuran jumping performance resembled data from metamorph L. peronii. Although the hindlimbs of post-metamorphic L. peronii scaled geometrically (body mass exponent approximately 0.33), the hindlimbs of metamorphs showed greater proportional increases with body mass (mass exponents of 0.41-0.42).

scholarly journals The dynamics of starvation and recovery

2017 ◽  
Author(s):  
Justin D. Yeakel ◽  
Christopher P. Kempes ◽  
Sidney Redner
Keyword(s):  
Population Dynamics ◽  
Allometric Scaling ◽  
Evolutionary Dynamics ◽  
Percent Body Fat ◽  
Structured Model ◽  
Homogeneous Population ◽  
Population Extinction ◽  
Scaling Relationships ◽  
Energetic Constraints ◽  
Cope’S Rule

The eco-evolutionary dynamics of species are fundamentally linked to the energetic constraints of its constituent individuals. Of particular importance is the interplay between reproduction and the dynamics of starvation and recovery. To elucidate this interplay, we introduce a nutritional state-structured model that incorporates two classes of consumer: nutritionally replete, reproducing consumers, and undernourished, non-reproducing consumers. We obtain strong constraints on starvation and recovery rates by deriving allometric scaling relationships and find that population dynamics are typically driven to a steady state. Moreover, these rates fall within a ‘refuge’ in parameter space, where the probability of population extinction is minimized. We also show that our model provides a natural framework to predict maximum mammalian body size by determining the relative stability of an otherwise homogeneous population to a competing population with altered percent body fat. This framework provides a principled mechanism for a selective driver of Cope’s rule.

Superlinear scaling of riverine biogeochemical function with watershed size

2021 ◽  
Author(s):  
Wilfred Wollheim ◽  
Tamara Harms ◽  
Andrew Robison ◽  
Lauren Koenig ◽  
Ashley Helton ◽  
...  
Keyword(s):  
Allometric Scaling ◽  
Spatial Scales ◽  
River Networks ◽  
Power Exponent ◽  
Earth System ◽  
Network Function ◽  
Scaling Relationships ◽  
The Earth ◽  
Watershed Size

Abstract River networks are a crucial component of the earth system because they regulate carbon and nutrient exchange between continents, the atmosphere, and oceans. Quantifying the role of river networks at broad spatial scales must accommodate spatial heterogeneity, discharge variability, and upstream-downstream connectivity. Allometric scaling relationships of cumulative biogeochemical function with watershed size integrate these factors, providing an approach for understanding the role of fluvial networks in the earth system. Here we demonstrate that allometric scaling relationships of cumulative river network function are linear (power exponent ~ 1) when biogeochemical reactivity is high and river discharges are low, but become increasingly superlinear (power exponent > 1) as reactivity declines or discharge increases. Superlinear scaling indicates that biogeochemical function of entire river networks within a watershed is an emergent property that increases disproportionately with increasing watershed size. Expanding observation networks will increase precision in riverine fluxes of carbon and nutrients estimated by allometric scaling functions.

scholarly journals Supraceliac and Infrarenal Aortic Flow in Patients with Abdominal Aortic Aneurysms: Mean Flows, Waveforms, and Allometric Scaling Relationships

2010 ◽  
Vol 1 (1) ◽  
pp. 39-51 ◽  
Author(s):  
Andrea S. Les ◽  
Janice J. Yeung ◽  
Geoffrey M. Schultz ◽  
Robert J. Herfkens ◽  
Ronald L. Dalman ◽  
...  
Keyword(s):  
Allometric Scaling ◽  
Abdominal Aortic Aneurysms ◽  
Aortic Aneurysms ◽  
Aortic Flow ◽  
Scaling Relationships ◽  
Abdominal Aortic
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