Optimality Models and the Test of Adaptationism

1994 ◽  
Vol 143 (3) ◽  
pp. 361-380 ◽  
Author(s):  
Steven Hecht Orzack ◽  
Elliott Sober
Keyword(s):  
Optimality Models

scholarly journals The comparative biology of second sex ratio evolution within a natural population of a parasitic wasp, Nasonia vitripennis.

Genetics ◽  
1990 ◽  
Vol 124 (2) ◽  
pp. 385-396 ◽  
Author(s):  
S H Orzack
Keyword(s):  
Sex Ratio ◽  
Parasitic Wasp ◽  
Comparative Biology ◽  
Significant Heterogeneity ◽  
Regression Analyses ◽  
Nasonia Vitripennis ◽  
Second Sex ◽  
Sex Ratio Adjustment ◽  
Optimality Models ◽  
Isofemale Strains

Abstract Correlation and regression analyses indicate that isofemale strains extracted from a population of the parasitic wasp, Nasonia vitripennis, differ in the fit of their second sex ratios (those produced in previously parasitized hosts) to the predictions of the theory of optimal facultative sex ratio adjustment. Under the theory's simple assumptions about population structure, there is significant heterogeneity of fitnesses among the isofemale strains. The reasons underlying these types of heterogeneity must be understood before we can make statements about the nature of sex ratio evolution in this species. These results suggest that comparative analyses are essential for testing the qualitative predictions of optimality models.

Is the ‘Environment’ Good to Eat or Good to Paint? Faunal Consumption and Avoidance among Hunter-Gatherer-Fishers in the Beagle Channel Region (Tierra del Fuego, South America)

2013 ◽  
Author(s):  
Dánae Fiore ◽  
Angélica Tivoli
Keyword(s):  
South America ◽  
Tierra Del Fuego ◽  
Human Environment ◽  
Beagle Channel ◽  
Archaeological Data ◽  
Hypothetical Scenario ◽  
Human Practices ◽  
Industrial Societies ◽  
Optimality Models ◽  
Channel Region

This chapter discusses some aspects of the multi-dimensional nature of human–environment relationships. It focuses on the interaction established between people and animals in the Beagle Channel region (Tierra del Fuego, South America; Figure 5.1) through an analysis of taxon selection or avoidance in two inter-related spheres: subsistence and ceremonial art. The selection or avoidance of a particular species can be related to environmental, economic, political, and ideological factors, and our aim is to point out which of these factors influenced the high exploitation of certain taxa and the low representation of others. We achieve this by comparing archaeological data with spatially and temporally contemporaneous ethnographic information about the representation of animal species in ceremonial body paintings. Thus, we seek to explain whether the selection of some species and the avoidance of others in the subsistence sphere was being reinforced by or forbidden according to symbolic values that stemmed from the ceremonial sphere. Such questions derive from a theoretical premise that dismisses the notion of absolute optimality in human practices. It proposes instead that people’s actions and decisions are not guided only by rational principles and cost-minimizing aims: they can also be non-rational and non-optimal, and yet can make a socio-economic system function and reproduce efficiently through time and space without collapse. We argue that archaeological techniques and data have much to contribute to an understanding of the complexity of human–environment relations—particularly the ability to critique the overly simplistic economic models that often feed into popular and bureaucratic approaches to human environments. During the last fifteen years, one of the most popular approaches to subsistence in prehistoric and non-industrial societies has been the application of optimality models (e.g. Broughton 1994; Grayson and Delpech 1998; Nagaoka 2002, among others). In principle, these models were conceived as methodological tools through which the researcher lays out a hypothetical scenario of how resources should be consumed if people were trying to minimize costs and maximize benefits towards reaching an optimal result.

scholarly journals Optimality Models and the Propensity Interpretation of Fitness

2019 ◽  
Vol 68 (3) ◽  
pp. 367-385
Author(s):  
Ariel Jonathan Roffé ◽  
Santiago Ginnobili
Keyword(s):  
Optimality Models ◽  
Propensity Interpretation

scholarly journals Is Amphistomy an Adaptation to High Light? Optimality Models of Stomatal Traits along Light Gradients

2019 ◽  
Vol 59 (3) ◽  
pp. 571-584 ◽  
Author(s):  
Christopher D Muir
Keyword(s):  
Energy Budget ◽  
Water Loss ◽  
R Package ◽  
High Light ◽  
Carbon Gain ◽  
Marginal Effect ◽  
Costs And Benefits ◽  
Leaf Surfaces ◽  
Stomatal Traits ◽  
Optimality Models

AbstractStomata regulate the supply of CO2 for photosynthesis and the rate of water loss out of the leaf. The presence of stomata on both leaf surfaces, termed amphistomy, increases photosynthetic rate, is common in plants from high light habitats, and rare otherwise. In this study I use optimality models based on leaf energy budget and photosynthetic models to ask why amphistomy is common in high light habitats. I developed an R package leafoptimizer to solve for stomatal traits that optimally balance carbon gain with water loss in a given environment. The model predicts that amphistomy is common in high light because its marginal effect on carbon gain is greater than in the shade, but only if the costs of amphistomy are also lower under high light than in the shade. More generally, covariation between costs and benefits may explain why stomatal and other traits form discrete phenotypic clusters.

Reproduction of salal (Gaultheriashallon) under forest canopy

1990 ◽  
Vol 20 (1) ◽  
pp. 91-100 ◽  
Author(s):  
F. L. Bunnell
Keyword(s):  
Sexual Reproduction ◽  
Forest Canopy ◽  
Vegetative Reproduction ◽  
Resource Limitation ◽  
Shoot Density ◽  
Physiological Integration ◽  
Forest Canopies ◽  
Plant Persistence ◽  
Crown Closure ◽  
Optimality Models

Sexual and vegetative reproduction of salal (Gaultheriashallon Pursh) was measured under forest canopies of different closure. Sexual reproduction occurred only at ≤33% closure; vegetative reproduction occurred under sparse and dense closure. Crown closure influenced sexual reproduction primarily through interception of radiation and associated reductions in salal vigour. Irradiance had a greater influence on the mode of reproduction than did shoot density, and allocation of total reproductive effort (sexual plus vegetative) was contrary to optimality models, but consistent with resource limitation. No shoot <5 years old flowered; shared costs of flowering indicated physiological integration among salal shoots. Vegetative reproduction was negatively associated with age (r2 = 0.95), and 85% of the space occupied after 9 years of growth was occupied during the first 3 years. Under canopy the spatial pattern of salal shoots was better adapted to maintain plant persistence than to colonize new areas. Implications of salal's rates and modes of reproduction to forest and wildlife management are noted.

Should I stay or should I go? Testing optimality models of stopover decisions in migrating birds

1999 ◽  
Vol 46 (4) ◽  
pp. 280-286 ◽  
Author(s):  
Thomas P. Weber ◽  
Thord Fransson ◽  
Alasdair I. Houston
Keyword(s):  
Migrating Birds ◽  
Optimality Models
Sign in / Sign up

Export Citation Format

Share Document