Presentation on theme: "Eric Pianka Karen Bascom Community Ecology Spring 2014"— Presentation transcript:
Eric Pianka Karen Bascom Community Ecology Spring 2014
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.”
Early Life Born 1939, Siskiyou Co., California Bazooka explosion injury (You thought EO Wilson had a cool story)
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.
Text-Wall of Publications
Latitudinal Gradients in Species Diversity Published as a Graduate Student! In review: Time Spatial Heterogeneity Competition Predation Climatic Stability Productivity Pianka 1966a
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)
Optimal Foraging Theory “Patchy” Environments Potential prey items separated into discrete areas MacArthur & Pianka 1966
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 archive.html
OFT In Desert Lizards Cnemidophorus “Jack-of-all-Trades” Wide Foraging “Convex” Phrynosoma “Sit and Wait” Specialist Ants Pianka 1966b
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
Niche Overlap and Diffuse Competition Building on ideas from Elton, Hutchinson, MacArthur and May Pianka 1974
Niche Overlap and Diffuse Competition Niche Overlap Maximum overlap varies inversely with competition Does not imply competition There may actually be less! Diffuse Competition Total effects of interspecific competitors Strength of inhibition and number of competitors considered Pianka 1974
Niche Overlap and Diffuse Competition Desert Lizard Diversity and Density Environmental Variation Trophic, Spatial, and Temporal Niche Dimensions Australia North America Africa Pianka 1974
Niche Overlap and Diffuse Competition Pianka 1974 Overlap between pairs decreases, but total overlap in the community increases
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
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
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
Recent Work Fire Cycles in Western Australia Phylogenetics of Varanids and Skinks Cataloging
Effects of Fire Cycle on Lizards Pianka & Goodyear 2012
He’s Not Dead, Yet!
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: 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.