1. Karen Bascom Community Ecology Spring 2014
Eric Pianka
Karen Bascom
Community Ecology
Spring 2014

2. Who is “The Lizard Man”?
Current Position: Denton A. Cooley Centennial Professor of Zoology, University of Texas-Austin
Ecology of Desert Lizards
Research Interests (from his department website):
“My interests are ever changing but have included population and community ecology, evolutionary ecology, natural history of desert lizards, resource partitioning, reproductive tactics, foraging theory, allocation, design constraints, thermoregulation, rarity, metapopulations, historical accident and biogeography, species diversity, macrodescriptors, pseudocommunities, phylogenetic systematics, computer simulation of model systems, emergent properties of ecological systems, indirect interactions among populations, disturbance, metapopulations, fire ecology, succession, landscape ecology, and using phylogenies to reconstruct probable ancestral states and deduce the course of evolution.”

3. Early Life Born 1939, Siskiyou Co., California
Bazooka explosion injury
(You thought EO Wilson had a cool story)

4. Education and Honors BA: Carleton College, 1960
PhD: University of Washington, 1965
Post-Doctoral Study: Princeton University
Guggenheim Fellow, 1978
Fellow, American Association for the Advancement of Science, 1981
Fulbright Senior Research Scholar, Australia, 1990
D. Sc., (Ecology), University of Western Australia, 1990
Fellow, Ecological Society of America, 2013.

5. Text-Wall of Publications

6. Books

7. Latitudinal Gradients in Species Diversity
Published as a Graduate Student!
In review:
Time
Spatial Heterogeneity
Competition
Predation
Climatic Stability
Productivity
Pianka 1966a

8. On Optimal Use of a Patchy Environment
Pianka’s First “Citation Classic”
Economical choices in food selection
Principle: Energy Gains>Energy Losses
“Optimal Foraging Theory” (OFT)

9. Optimal Foraging Theory
“Fine-Grained” Environments
Potential prey items proportionally distributed
MacArthur & Pianka 1966

10. Optimal Foraging Theory
“Patchy” Environments
Potential prey items separated into discrete areas
MacArthur & Pianka 1966

11. Optimal Foraging Theory
Strategies differ between fine-grained and patchy environments
Competition
“Jack of all trades” will outcompete Specialist at low search times
Generalist will outcompete Jack at higher food densities
MacArthur & Pianka 1966

12. OFT In Desert Lizards Cnemidophorus Phrynosoma “Jack-of-all-Trades”
Wide Foraging “Convex”
Phrynosoma
“Sit and Wait”
Specialist
Ants
Pianka 1966b

13. Influence of OFT >1750 Citations
Inspired empirical testing of behavioral ecology
“Convexity, Desert Lizards, and Spatial Heterogeneity” (Pianka 1966b)
Anthropology and Human Evolution
Criticism
How does one measure the “Optimum”?
“Do bumblebees forage optimally, and does it matter?” (Heinrich 1983)
Newer adaptations incorporate other ecological factors
Perry & Pianka 1997

14. Niche Overlap and Diffuse Competition
Building on ideas from Elton, Hutchinson, MacArthur and May
Pianka 1974

15. Niche Overlap and Diffuse Competition
Maximum overlap varies inversely with competition
Does not imply competition
There may actually be less!
Total effects of interspecific competitors
Strength of inhibition and number of competitors considered
Pianka 1974

16. Niche Overlap and Diffuse Competition
North America
Africa
Australia
Desert Lizard Diversity and Density
Environmental Variation
Trophic, Spatial, and Temporal Niche Dimensions
Pianka 1974

17. Niche Overlap and Diffuse Competition
Overlap between pairs decreases, but total overlap in the community increases
Pianka 1974

18. Niche Overlap and Diffuse Competition
Provides empirical support for niche overlap hypothesis
Diffuse effects contribute to maximum overlap more than environmental variables and should be considered in models
Pianka 1974

19. On r- and K- Selection Extension of MacArthur and Wilson
Bimodal distribution of generation time
Annual cycles are a possible cause
Body size
Pianka 1970

20. Influence of On r- and K-selection
Perhaps too simplified?
“Physics has friction less hockey pucks, thermodynamics has Carnot engines, and evolutionary ecology has r- and K-selection.” (Mueller 1997)
Transition to age-specific mortality
Reznick et al 2002

21. Recent Work Fire Cycles in Western Australia
Phylogenetics of Varanids and Skinks
Cataloging

22. Effects of Fire Cycle on Lizards
Pianka & Goodyear 2012

23. He’s Not Dead, Yet!

24. Works Cited
MacArthur, RH and ER Pianka On optimal use of a patchy environment. The American Naturalist 100:
Perry, G and ER Pianka Animal foraging: past, present, and future. Trends in Ecology and Evolution 12:
Pianka, ER Latitudinal gradients in species diversity: A review of concepts. The American Naturalist 100:33-46.
Pianka, ER Convexity, desert lizards, and spatial heterogeneity. Ecology 47:
Pianka, ER On r- and K-selection. The American Naturalist 104:
Pianka, ER The structure of lizard communities. Annual Review of Ecology and Systematics 4:3-74.
Pianka, ER Overlap and diffuse competition. Proceedings of the National Academy of Sciences of the United States of America 71:
Pianka, ER and SE Goodyear Lizard responses to wildfire in arid interior Australia: Long-term experimental data and commonalities with other studies. Austral Ecology 37:1-11.
Reznik, D, MJ Bryant, and F Bashey r- and K-selection revisited: The role of population regulation in life-history evolution. Ecology, 83:
University of Texas-Pianka Webpage.

25. Any Questions?