First Exam Thursday 18 February Covers Chapters 1-4, 6-7 plus Chapter 16 and first 8 lectures, 5 discussions, plus 8 Readings: Scientific Methods Natural Selection Human Nature Our Hunter-Gatherer Heritage Evolution of Uncaring Humanoids Unburnable Oil Population Growth Evolution’s Problem Gamblers

Principle of Allocation Tolerance Curves Ray Huey Principle of Allocation

Principle of Allocation Tolerance Curves Ray Huey Principle of Allocation

Principle of Allocation Tolerance Curves Ray Huey Principle of Allocation

Performance plotted against temperature Acclimation Performance plotted against temperature

Hypothetical response curves showing interactions

Resource Budgets Principle of Allocation Time, Matter, and Energy Budgets Rock Pipits Anthus spinoletta Mild Winter versus Harsh Winter Feeding: 6.5 hours vs. 8.25 hours Resting: 1.75 hours vs. 0.6 hours Fighting: 0.75 hours vs. 0.1 hour

Leaf Tactics Light Water availability Prevailing winds Herbivores Costs and Profits of Leaf Size, Shape, and Placement

Leaf Tactics Similar types of leaves have evolved independently in different plant lineages subjected to comparable climatic conditions Compound leaves conserve woody tissue Small leaflets in hot dry regions, but larger under warm moist conditions Shade tolerant understory species usually have larger and less lobed leaves than canopy species Lobed leaves do not cast as dense and solid a shadow as do leaves with continuous margins

In lowland wet tropical rainforest, trees tend to have large evergreen leaves In chaparral, plants tend to have small sclerophyllous evergreen leaves Arid regions tend to support leafless stem succulents such as cacti or plants with entire leaf margins Cold wet climates tend to support plants with notched or lobed leaf margins

Adaptive Geometry Evergreen vs Adaptive Geometry Evergreen vs. Deciduous Monolayered vs Multilayered plants Shade Tolerance

Plant Life Forms Evergreen vs Plant Life Forms Evergreen vs. Deciduous Monolayered vs Multilayered plants Shade Tolerance Xerophytic vs. Mesophytic leaves Also Hydrophytes (water lilies)

Gordon Orians Otto Solbrig

Plant Life Forms Evergreen vs Plant Life Forms Evergreen vs. Deciduous Monolayered vs Multilayered plants Shade Tolerance Xerophytic vs. Mesophytic leaves Also Hydrophytes (water lilies) Creosote Bush Larrea divaricata-- Mesquite Prosopis -------

Foraging Tactics and Feeding Efficiency Costs and Profits of Foraging An optimal foraging tactic maximizes the difference between foraging profits and their costs Food = matter and energy for maintenance and reproduction Hazards: exposure to predators, loss of time for other activities Sit-and-Wait ambush predators (e.g. spiders at webs) Widely foraging active hunters (go out and find prey) Search Time (per item eaten) versus Pursuit Time (per item eaten) Search for all possible prey items, but pursue them one at a time Prey items can be ranked from most preferred to least desirable

“Economics of Consumer Choice” Assumptions: a) Environmental structure is repeatable, with statistical expectation of finding a given resource (habitat, microhabitat, or prey item) b) Food items can be arranged along a continuous spectrum, such as by size or energy reward c) Similar phenotypes are closely equivalent in harvesting abilities d) Principle of Allocation applies: no one phenotype can be maximally efficient on all prey types e) An individual’s economic “goal” is to maximize its total intake of food resources Robert MacArthur

“Economics of Consumer Choice” Four Phases of Foraging: “Economics of Consumer Choice” Four Phases of Foraging: 1) deciding where to search 2) searching for palatable food items 3) upon locating a potential food item, deciding whether or not to pursue it 4) pursuit itself, with possible capture and eating Search and pursuit efficiencies for each food type in each habitat are entirely determined by preceding assumptions about morphology and environmental repeatability. These efficiencies dictate probabilities associated with search and pursuit (phases 2 and 4) . Thus, need to consider only the two decisions: where to forage and which prey items to pursue (phases 1 and 3 above) Robert MacArthur

“Economics of Consumer Choice” (R. H “Economics of Consumer Choice” (R. H. MacArthur) Clearly, an optimal consumer should forage where its expectation of yield is greatest — an easy decision to make, given knowledge of efficiency probabilities and the structure of the environment (of course, in reality, animals are not omniscient and must make decisions based on incomplete information). The decision as to which prey items to pursue is also simple. Upon finding a potential prey item, a consumer has just two options: either pursue it or go on searching for a better item and pursue that one instead. Both decisions end in the forager beginning a new search, so the best choice is clearly the one that returns the greatest yield per unit time. An optimal consumer should opt to pursue an item only when it cannot expect to locate, catch and eat a better item during the time required to capture and ingest the first prey item.

From Huey and Pianka 1981 Ecology 62: 991-999.

C. S. Holling

400 Frames per second (3/100ths of a second) Tom Frazzetta Thomas Frazzetta 400 Frames per second (3/100ths of a second)

Physiological Ecology Homeostasis: maintenance of a relatively stable internal state under a much wider range of external environmental conditions Temperature regulation (thermoregulation) Physiological Optima and Tolerance Curves Acclimation

Energetics of Metabolism and Movement Ingestion = Assimilation + Egestion Assimilation = Productivity + Respiration Productivity = Growth + Reproduction Ingestion = Egestion + {Respiration + Growth + Reproduction} {Assimilation} ------------------------------------------------ Homeotherm versus Poikilotherm Endotherm versus Ectotherm

Body Mass, grams

Log,

Metabolic Cost of Movement Log, Log,

Metabolic Cost of Movement Log, Log,

Metabolic Cost of Movement Log, Log,

Adaptation and Deterioration of Environment Ronald A. Fisher Non-directed (random) changes in either A or B are equally likely to reduce the level of adaptation (d ) when small, but as the magnitude of undirected change increases, the probability of improvement diminishes. Duality of Fisher’s model (A and B can be interchanged)

Water Economy in Desert Organisms Other Limiting Materials Sensory Capacities and Environmental Cues Adaptive Suites Design Constraints

Heat Budgets and Thermal Ecology