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Department of Paleobiology

  • Peter Wagner
  • Curator of Paleozoic Molluscs
  • Phone:   202-633-1345
  • Fax:   202-786-2832
  • E-mail Address:   wagnerpj
  • Mailing Address:
    Smithsonian Institution
    PO Box 37012, MRC 121
    Washington, DC 20013-7012
  • Shipping Address:
    Smithsonian Institution
    National Museum of Natural History
    10th & Constitution NW
    Washington, DC 20560-0121


  • Ph.D. Geophysical Sciences University of Chicago 1995, Thesis Title:  "The generation and maintenance of morphologic and phylogenetic diversity among early gastropods."
  • M.S. Geological Sciences Michigan State University 1990, Thesis Title:  "Phylogenetic analysis of the Lophospiridae (Gastropoda: Pleurotomariina) of the Ordovician and Silurian."
  • B.S. Geological Sciences Michigan State University 1989
  • B.S. Anthropology/Zoology University of Michigan, Ann Arbor 1986

Research Interests

The fundamentals of my research revolve around phylogenetic relationships among Paleozoic molluscs. The majority of my work has been on Cambrian - Devonian anisostrophic gastropods, although I've started dabbling with bellerophont gastropods also.  I also have worked with a more obscure and entirely extinct group, the Rostroconchia.

The primary purpose of this phylogenetic work is to provide a template for the macroevolutionary studies discussed below. However, it also has resulted in an extensive taxonomic revision of Early Paleozoic gastropods.

The main macroevolutionary issues that I have studied concern rates of morphologic evolution. I have been particularly interested in how those rates might change over time, especially after the early Paleozoic. The goal of these studies has been to test a variety of hypotheses (most proposed by Jim Valentine) about why such a disproportionate number of basic metazoan types appeared in the very early Phanerozoic. Gastropods represent one such taxon. The bulk of gastropod morphospace was produced very rapidly. Subsequent evolution in the major clades failed to produce the same range of variation even after the evolution of many more species over many tens of millions of years. When morphologic separations between ancestors and descendants were examined, a highly significant decrease over time was found. Intriguingly, the decrease focused on particular types of shell differences. Among modern snails, these types of differences are observed among taxa with very different soft anatomies. Another set of differences showed very little change in evolutionary potential over time. Among modern snails, these differences are common among close relatives and often reflect differences in specific ecology.

My early work used inferred phylogenies as models for testing various hypotheses.  I found this approach dissatisfying because it was inherently biased towards supporting hypotheses matching the assumptions of the initial analysis.  I dabbled in using stratigraphy to test individual nodes but this was not entirely satisfying either as it could correct flawed initial assumptions only under particular circumstances.  This led me toward likelihood tests.  Fundamentally, I used morphologic and stratigraphic data to test multiple hypotheses simultaneously.  This is best expressed as: >L[t, C | CD, SD]
or (in English), the likelihood of phylogeny (t) and character evolution (C) given character data and stratigraphic data, which is equal to the probability of the data given the hypotheses.  The math actually is pretty simple, although it is very different from the approaches used by molecular workers.  Ultimately, I wish to test hypotheses about rates of character evolution, both among characters and over time.  Also, I am interested in testing hypotheses about driven trends (i.e., the tendency for a character to evolve into a particular state).  Ultimately, one can contrast
L[t1, C1 | CD, SD] with the more complicated L[t2, C2 | CD, SD]
where C2 is a hypothesis positing a greater number of different rates (over time, among characters, between character states, etc.).  Different trees (t1 and t2) are used to maximize the likelihoods of the null and test hypotheses.  This way, both hypotheses get their best shot.  Stratigraphic data serve as an arbitrator of sorts.  I currently am writing programs to implement this approach (and boy, it's tough!)

4. Long term evolutionary dynamics.

Evolutionary biologists traditionally assumed that relationships existed between basic morphologies and factors affecting evolutionary potential (i.e., rates of speciation and extinction). More recently, cladists have challenged this idea, asserting that only monophyletic groups have any biological reality. The truth of the matter is that associations between gross evolutionary patterns and morphology have not been adequately examined. My current research tests this question using Paleozoic gastropods, by examining the relationship between extinction dynamics and gross morphology (especially that associated with very basic ecologic strategies, e.g., sessile suspension feeders vs. mobile detriti-/herbi-/carnivores).
Diversity studies, phylogenetic analyses and morphospace studies all require detailed stratigraphic data. To this end, I have compiled a large number of species lists that identify the species present at particular localities. As you can see, snails are known from an awful lot of localities. The scary thing is that the fossil records of many other groups is a lot better.
The effect of distributions on sampled richness.

Positions Held

  • Research Scientist, National Museum of Natural History, Smithsonian 10/07 - present
  • Research Associate, National Museum of Natural History, Smithsonian 4/05 - 9/07
  • Lecturer, University of Chicago, Committee on Evolutionary Biology 6/98 - 9/07
  • Curator, Field Museum 9/96 - 9/07
  • Smithsonian Postdoctoral Fellow 9/95 - 8/96

Financial Awards and Support

  • Testing the generality of macroevolutionary dynamics with bellerophont molluscs ($68,221) Aug. 2002 - July 2008
  • NSF Research Grant EAR-9903238 - “Evolutionary dynamics among Early- Middle Devonian gastropods” ($72,444) Aug. 1999 - July 2004
  • NSF Collections Grant EAR-9728991 - "Support for the Field Museum fossil invertebrate collections ($64,620) June 1998 - July 2001
  • NSF Research Grant DEB-9213977 - “Phylogenetic and morphometric analysis of Early Paleozoic  archaeogastropods”  ($10,000) Oct.1992 - Sept. 1995
  • Sigma Xi June 1992
  • Hinds Fund, Biological Sciences Division, U. Chicago April 1992
  • Geological Society of America March 1992
  • Smithsonian Institution Predoctoral Fellowship April 1991
  • Harper Fellowship, University of Chicago Oct. 1994 - Sept. 1995
  • Pringle Fellowship, Geological Sciences Dept., M.S.U. May 1990
  • Teaching/Research Assistantships (U. Chicago) Oct. 1990 - August 1995
  • Teaching Assistantships (Michigan State University) April 1989 - June 1990

Honors / Awards

  • Charles Schuchert Award, Paleontological Society November 2004
  • Best Student Paper, American Malacological Union June 1993
  • Outstanding Research Proposal, Geological Society of America June 1992

Professional Services

  • Editor, Paleobiology (2007 - present)
  • Editorial Board, Palaeontologische Zeitschrift (2005 - present)
  • Science Advisory Board, National Evolutionary Synthesis Center (2005 - present)
  • Lecturer, Paleobiology Database "Quantitative Paleobiology" Short Course (Phylogenetics component), 2005, 2006, 2007, 2008.
  • Officer Nominations Committee, the Paleontological Society (1999- 2002)
  • Advisory Board, Paleobiology Database (2000- 2005)
  • Reviewer for: Paleobiology, Journal of Paleontology, Systematic Biology, Proceedings of the Royal Society of London, Evolution, Palaeontology, Science, Journal of Systematic Palaeontology, Biological Bulletin, Journal of Evolutionary Biology, Lethaia, Biological Journal of the Linnean Society, Alcheringa, Geology, Journal of Geology, National Science Foundation, National Geographic, Society of Systematic Biology Graduate Student Grants (2000), The University of Chicago Press.

Working Groups

  • Fossil and Molecular Estimates of Divergence Times for the Tree of Life: Database and Synthesis: Sept. 2006 - Present (Todd Oakley, head: National Evolutionary Synthesis Center, Durham NC)
  • Adaptive Radiations Aug. 2001 - 2004. (Jonathan Losos, head; National Center for Ecological Analysis & Synthesis, Santa Barbara CA).
  • Paleobiology Database (PBDB) Project Aug. 1998 - Present (John Alroy & Charles Marshall, heads; National Center for Ecological Analysis & Synthesis, Santa Barbara CA).
  • Co-chair of Taxonomy Subgroup for PBDB.



  • Jon Marcot (Co-Chair) (Committee on Evolutionary Biology, U. Chicago; completed 2003)
  • John Finarelli (Co-Chair) (Committee on Evolutionary Biology, U. Chicago; completed 2007)
  • Emily Allen (Committee on Evolutionary Biology, U. Chicago; completed 2005)
  • Allison Beck (Committee on Evolutionary Biology, U. Chicago; completed 2004)
  • Matthew Friedman (Committee on Evolutionary Biology, U. Chicago; completed 2009)
  • Anjali Goswami (Committee on Evolutionary Biology, U. Chicago; completed 2005)
  • Bjarte Hannisdal (Geophysical Sciences, U. Chicago; completed 2006)
  • Annat Haber (Committee on Evolutionary Biology, U. Chicago)
  • Paul Harnik (Geophysical Sciences, U. Chicago; completed 2009)
  • Melanie Hopkins (Geophysical Sciences, U. Chicago)
  • Christian Kammerer (Committee on Evolutionary Biology, U. Chicago; completed 2009)
  • Kimberly Koverman (Geophysical Sciences, U. Chicago)
  • Lee Hsiang Liow (Committee on Evolutionary Biology, U. Chicago; completed 2006)
  • Virginia Miller (Committee on Evolutionary Biology, U. Chicago)
  • Rebecca Price (Geophysical Sciences, U. Chicago; completed 2003)
  • Tom Rothfus (Geophysical Sciences, U. Chicago; completed 2005)
  • Carl Simpson (Geophysical Sciences, U. Chicago; completed 2006)
  • Melinda Brady (Committee on Evolutionary Biology, U. Chicago; completed 2000)
  • Robin O’Keefe (Committee on Evolutionary Biology, U. Chicago; completed 2000)
  • Rudyard Sadlier (Committee on Evolutionary Biology, U. Chicago)
  • Chris Sidor (Organismal Biology & Anatomy, U. Chicago; completed 2000)
  • Hallie Sims (Geophysical Sciences, U. Chicago, completed 2000)
  • Jeff Wilson (Anatomy, U. Chicago; completed 1999)


  • Phil Gottshall (Geology, U. Cincinnati; completed 1999)
  • Andrea Lofgren (Geology, U. Illinois, Chicago; completed 2000)


  • Andrew Rominger (Summer 2008)
  • Michael Nakagaki (Summer 2008)
  • Alexei Rivera (Summer 1999)
  • Kimberly Koverman (Summer 1997)


  • Western Australia (Ordovician, Devonian & Carboniferous). (7/04)
  • Antelope Valley Formation (Ordovician) / Ely Dolomite (Ordovician) (9/00)
  • Lost Burro Formation (Devonian) / Antelope Valley Formation (Ordovician), Nevada / California (4/99)
  • Lost Burro Formation (Devonian), Death Valley National Park (5/98)


  • January 2007 - Present: Paleobiology Department Representative, Fellowship Committee.
  • November 2007 - Present: Alternate, Paleobiology representative, Senate of Science
  • November 2006: Presentation for Friends of Geology donors group.
  • November 2003: "Introduction to museum research" lecture (Committee on Evolutionary Biology)
  • November 2002: "Introduction to museum research" lecture (Committee on Evolutionary Biology)
  • May 2001 - May 2004: Academic Affairs Information Technology Subcommittee (Chair).
  • May 2001 - May 2004: Library Committee.
  • January 2001 - May 2004: Information Technology Committee.
  • November 2000: "Introduction to museum research" lecture (Committee on Evolutionary Biology)
  • October 2000 - August 2002: Academic Affairs representative for "Kaffeklatsch" / Roundtable.
  • July 2000: Presentation on FMNH / University of Chicago interactions to the Dean of Physical Sciences
  • September 1999 - October 2000: Organizer, A. Watson Armour III Symposium "The history of biodiversity."
  • April - December 1999: Chair, Paleobotany search committee
  • May 1999: Science Olympiad judge.
  • December 1998: Outside member of Zoology search committee (entomology position)
  • November 1998: "Introduction to museum research" lecture (Committee on Evolutionary Biology)
  • Summer 1998: Co-organizer "Summer Symposium Series."
  • April 1998: Organizer A. Watson Armour III Spring Symposium "Combining molecular and paleontological data."
  • February 1997: "Introduction to Invertebrate Paleontology" lecture for museum volunteers.
  • November 1996: "Introduction to museum research" lecture (Committee on Evolutionary Biology)
  • Nov. 1996 - August 2007: Ongoing: Maintenance and development of departmental server and online database.
  • Nov. 1996 - August 2007: Maintenance and development of Geology image analysis laboratory.



Lyons, S. K., and P.J. Wagner.  2009I.  Using macroecological approach to the fossil record to help inform conservation biology.  Pp. 141 - 166 in G. P. Dietl and K. W. Flessa, eds. Conservation biology. Using the past to manage for the future.  Paleontological Society, New Haven, Connecticut.

McElwain, J.C., P.J. Wagner & S.P. Hesselbo. 2009 R. Fossil plant relative abundances indicate sudden loss of Late Triassic biodiversity in Greenland. Science 324:1554-1556.

Frýda, J., A. Nützel and P.J. Wagner. 2008 I . Paleozoic Gastropoda, pp. 239 - 270 in W.F. Ponder & D.R. Lindberg, eds. Phylogeny and evolution of the Mollusca. U. California Press, Berkeley.

Alroy, J., M. Aberhan, D.J. Bottjer, M. Foote, F.T. Fürsich, P.J. Harries, A.J.W. Hendy, S.M. Holland, L.C. Ivany, W. Kiessling, M.A. Kosnik, C.R. Marshall, A.J. McGowan, A.I. Miller, T.D. Olszewski, M.E. Patzkowsky, S.E. Peters, L. Villier, P.J. Wagner, N. Bonuso, P.S. Borkow, B. Brenneis, M.E. Clapham, L.M. Fall, C.A. Ferguson, V.L. Hanson, A.Z. Krug, K.M. Layou, E.H. Leckey, S. Nürnberg, C.M. Powers, J.A. Sessa, C. Simpson, A. Tomasovych, & C.C. Visaggi.  2008 R.  Phanerozoic trends in the global diversity of marine invertebrates. Science 321:97 - 100. 

Coates, M.I., M. Ruta, & P.J. Wagner.  2007 I,R.  Using patterns of fin and limb phylogeny to test developmental-evolutionary scenarios.  Pp. 245-261 in G. Bock & J. Goode, eds. Tinkering: the microevolution of development. Wiley, New York.

 Wagner, P.J., M. Aberhan, A. Hendy & W. Kiessling. 2007R. The effects of taxonomic standardization on sampling-standardized estimates of historical diversity. Proceedings of the Royal Society B: Biological Sciences 274:439-444.

Kiessling, W., M. Aberhan, B. Brenneis & P.J. Wagner 2007R. Extinction trajectories of benthic organisms across the Triassic-Jurassic boundary. Palaeogeography, Palaeoclimatology, Palaeoecology 244:201-222.

Wagner, P.J., M.A. Kosnik & S. Lidgard. 2006R. Abundance distributions imply elevated complexity of post-Paleozoic marine ecosystems. Science 314:1289-1292. 

Ruta, M., P.J. Wagner & M.I. Coates.  2006R.  Evolutionary patterns in early tetrapods. I: Rapid initial diversification followed by decrease in rates of character change.  Proceedings of the Royal Society of London, Series B. Biological Sciences. 273:2107-2111.

Wagner, P.J., M. Ruta & M.I. Coates.  2006R.  Evolutionary patterns in early tetrapods. II: Differing constraints on available character space among clades.  Proceedings of the Royal Society of London, Series B. Biological Sciences. 273:2113-2118.

Madin, J.S., J. Alroy, M. Aberhan, F.T. Fürsich, W. Kiessling, M.A. Kosnik & P.J. Wagner. 2006R. Statistical independence of escalatory ecological trends in Phanerozoic marine invertebrates. Science 312:897 - 900.

Wagner, P.J. & D.H. Erwin. 2006R. Patterns of convergence in general shell form among Paleozoic gastropods.  Paleobiology 32: 315-336.

Kosnik, M.A. & P.J. Wagner.  2006R.  Effects of taxon abundance distributions on the number of taxa sampled.  Evolutionary Ecology Research 8:195-211. 

Plotnick, R.E. & P.J. Wagner. 2006R. Round up the usual suspects: occurrence distribution and wastebasket taxa in the fossil record.  Paleobiology 32:126-146.

Lyons, S.K., F.A. Smith, P.J. Wagner, E.P. White & J. Brown. 2004. Was a hyperdisease  responsible for the late Pleistocene megafaunal extinction? Ecology Letters7: 859-868.

Stockmeyer Lofgren, A, R. E. Plotnick & P.J. Wagner. 2003.  Morphological diversity of Carboniferous arthropods and insights on disparity patterns of the Phanerozoic. Paleobiology 29:350-369. 

Wagner, P.J. 2002I.  Excursions in macroevolution.  Evolution 56:1877-1879.

Wagner, P.J. 2002R.  Testing phylogenetic hypotheses with stratigraphy and morphology- a comment on Smith (2000).  Journal of Paleontology 51:590 - 593.

Wagner, P.J. 2001cI,R. Gastropod phylogenetics: progress, problems and implications.  Journal of Paleontology 75:1128 - 1140.

O’Keefe, F.R. & P.J. Wagner.  2001R.  Deriving and testing hypotheses of correlated character evolution using character compatibility. Systematic Biology 50: 657 - 675. 

Wagner, P.J.  2001bI.  Constraints on the evolution of form.  Pp. 154 - 159 in Palaeobiology 2 (D.E.G. Briggs & P. R. Crowther, eds.)  Blackwell, Oxford.

Wagner, P.J.  2001aR.  Rate heterogeneity in shell character evolution among lophospiroid gastropods.  Paleobiology 27:290 - 310.

Alroy, J., C. R. Marshall, R. K. Bambach, K. Bezusko, M. Foote, F. T. Fürsich, T. A. Hansen, S. M. Holland, L. C. Ivany, D. Jablonski, D. K. Jacobs, D. C. Jones, M. A. Kosnik, S. Lidgard, S. Low, A. I. Miller, P. M. Novack-Gottshall, T. D. Olszewski, M. E. Patzkowsky, D. M. Raup, K. Roy, J. J. John Sepkoski, M. G. Sommers, P. J. Wagner and A. Webber. 2001. Effects of sampling standardization on estimates of Phanerozoic marine diversity. Proceedings of the National Academy of Sciences, USA 98:6261 - 6266.

Wagner, P.J.  2000dI,R.  Phylogenetic analyses and the fossil record: tests and inferences, hypotheses and models.  Pp. 341 - 371in Deep time - Paleobiology’s perspective (D.H Erwin & S. L. Wing, eds.). Paleobiology Memoir 26.

Lutzoni, F., P.J. Wagner, V. Reeb & S. Zoller.  2000R.  Integrating ambiguously aligned regions of DNA sequences in phylogenetic analyses without violating positional homology.  Systematic Biology 49:628 - 651. 

Wagner, P.J.  & C.A. Sidor.  2000R.  Age rank / clade rank criteria: paraphyly, sampling, and the meaning of "stratigraphic consistency."   Systematic Biology 49:463 - 479.

Wagner, P.J.  2000cR.  Likelihood tests of hypothesized durations: testing for and accommodating biasing factors.  Paleobiology 26:431 - 449.

Wagner, P.J.  2000bR.  The exhaustion of morphological character states among fossil taxa.  Evolution 54:365 - 386.

Wagner, P.J.  2000aR.  The quality of the fossil record and the accuracy of phylogenetic inferences about sampling and diversity.  Systematic Biology 49:65 - 86.

Wagner, P.J.  1999bR.  Phylogenetics of the earliest anisostrophically coiled gastropods.  Smithsonian Contributions to Paleobiology 88:1 - 154. 

Wagner, P.J.  1999aR.  Phylogenetics of the Lophospiridae (Gastropoda: Murchisoniina) of the Ordovician and Silurian: the importance of stratigraphy and contrasts of different methods.  American Malacological Bulletin 15:1 - 31.

Wagner, P.J.  1998bR.  A likelihood approach for estimating phylogenetic relationships among fossil taxa.  Paleobiology 24:430 - 449.

Wagner, P.J.  1998aI.  Phylogenetic reconstruction and fossil data.  163 - 185 in The adequacy of the fossil record (S. K. Donovan & C. R. Paul, eds.).  John Wiley, London.

Wagner, P.J.  1997R.  Patterns of morphologic diversification among the Rostroconchia.  Paleobiology 23: 115 - 150.

Wagner, P.J.  1996bR.  Testing the underlying patterns of active trends.  Evolution 50: 990 - 1017.

Wagner, P.J.  1996aR.  Morphologic diversification during the initial radiation of "archaeogastropods."  161 - 169 in Origin and evolutionary radiation of the Mollusca (J. Taylor, ed.).  Oxford:  Oxford University Press.

Wagner, P.J.  1995dI.  Systematics and the fossil record [Book Review].  Palaios 10:383 - 388.

Wagner, P.J. & D.H. Erwin.  1995R.  Phylogenetic patterns as tests of speciation hypotheses.  87 - 122 in New approaches for studying speciation in the fossil record (D.H. Erwin & R.L. Anstey, eds.).  New York:  Columbia University Press.

Wagner, P.J.  1995cR.  Diversification among early Paleozoic gastropods - contrasting taxonomic and phylogenetic descriptions.  Paleobiology 21:410 - 439.

Wagner, P.J.  1995bR.  Testing evolutionary constraint hypotheses with early Paleozoic gastropods.  Paleobiology 21: 248 - 272.

Wagner, P.J.  1995aR.  Stratigraphic tests of cladistic hypotheses.  Paleobiology 21:153 - 178.

Papers accepted / in review

Wagner, P.J., & S.K. Lyons. 2010I.  Studying extinction with fossil data. In Frontiers in measuring biological diversity (A. Magurran & B. McGill, eds).  Oxford University Press, Oxford.
Wagner, P.J.. 2010. Paleontological perspectives on morphological evolution. In Evolution since Darwin: the first 150 Years (M.A. Bell, D.J. Futuyma, W.F. Eanes & J.S. Levinton, eds.) Sinauer, Sunderland.

Wagner, P.J.  accepted 11/97I,R.  The use of phylogenetic hypotheses in morphospace analyses.  in Morphospace concepts and applications (R. E. Chapman, M. Wills & D. Rasskin-Gutman, eds).  Columbia University Press, New York.

Manuscripts in Preparation

Marcot, J. & P.J. Wagner. Evaluating our understanding of relationships among fossil taxa.  To be submitted to Paleobiology.

Kosnik, M.A. & P.J. Wagner.  Evidence that basic ecological survives taphonomic filters. To be submitted to Proceedings of the National Academy of Sciences.

P.J. Wagner.  A simple inverse modeling method for estimating relative rates of character change prior to phylogenetic analysis.  To be submitted to Systematic Biology.

P.J. Wagner & G. Estabrook. On the compatibility between stratigraphy and anatomy: theoretical expectations, empirical observations, and macroevolutionary implications. To be submitted to Paleobiology.

Shareware Computer Programs

Wagner, P.J. & M.A.. Kosnik.  2008.  RAD 1.0. (Tests relative abundance distributions given sample sizes plus support bars on best fit distributions.).

Wagner, P.J. G.A. Estabrook & B. McMorris.  2008.  StratComp 1.0. (Tests whether character state distributions are compatible with stratigraphic distributions.).

Wagner, P.J. & F.R. O’Keefe.  2001.  CompCorr 1.0. (Tests whether mutual compatibility among characters could be achieved given independent character evolution.).

Wagner, P.J.  2001.  MCMLCompatibility 1.0.  (Determines the likelihood of observed compatibility given hypothesized amounts of character change).  

Wagner, P.J.  2000.  Exhaust 1.0.  (Tests character matrices for state exhaustion and tests alternative patterns of character state exhaustion.)

Wagner, P.J., F. Lutzoni, V. Reeb, S. Zoller. 2000.  INAASE 0.4c. (Determines most parsimonious comparative alignments among ambiguously aligned sequences.)

Refereed Abstracts

Wagner, P.J. & J.D. Marcot.  2008. Evaluating our understanding of different limbs of the metazoan Tree Of Life . Geological Society of America, Abstracts with Programs 40(6).

Wagner, P.J. 2008. Paleontological assessments of diversity dynamics .  Society of Integrative and Comparative Biology Annual Meeting. 

Wagner, P.J., & J.C. McElwain. 2007.  Using abundance distributions to analyze mass extinctions: Rapid diversity decrease among late Triassic plants coincident with climactic change . Ecological Society of America Annual Meetings.

Wagner, P.J., M.A. Kosnik & S. Lidgard. 2006.  Relative abundance distributions over the Phanerozoic: evidence for elevated complexity of post-Paleozoic marine ecosystems. Geological Society of America, Abstracts with Programs 38(6).

Wagner, P.J. & G.A. Estabrook 2005.  Evaluating the compatibility between morphological characters and stratigraphy. Geological Society of America, Abstracts with Programs 37(6).

Wagner, P.J. Morphologic diversification among Cambrian molluscs: contrasting precursors and progeny.  North American Paleontological Convention 2005. 

Wagner, P.J.  2003.  Likelihood tests of continuous versus speciational change. Geological Society of America, Abstracts with Programs 35(6):

Wagner, P.J.  2002.  Likelihood tests of general phylogenetic hypotheses: how many times did bellerophont molluscs evolve? Geological Society of America, Abstracts with Programs 34(7):

Wagner, P.J. & D.H. Erwin.  2001.  Evolution within a general shell-space among early gastropods.  Geological Society of America, Abstracts with Programs 33(7):A-125.

Kosnik, MA & P.J. Wagner. 2000. "Richness," "evenness," and abundance distribution effects on sampled "diversity": know when the data are leading you astray.  North American Paleontological Convention 2001 Abstracts of Papers.

Wagner, P.J. 2000. The effects of evenness on subsampling analyses of taxic richness.  Geological Society of America Abstracts with Programs 32(7):A-140.

Wagner, P.J. 1999. Assessing relative rates of shell character evolution among Paleozoic gastropods.  Geological Society of America Abstracts with Program 31(7):A-139.

Sidor, C.A. & P.J. Wagner.  1999.  What do age rank:clade rank tests reveal about the quality of the fossil record?  Geological Society of America Abstracts with Program 31(7):A-42.

O’Keefe, F.R. & P.J. Wagner.  1999. A compatibility-based method for assessing the independence of cladistic characters.  Geological Society of America Abstracts with Program 31(7):A-42.

Wagner, P.J.  1998.  Saturation of cladistic character space - debunking the myth of the infinite.  Geological Society of America Abstracts with Program 30(7):A-326.

Wagner, P.J.  1997.  Likelihood approaches for estimating from morphologic and stratigraphic data.  Geological Society of America, Abstracts with Programs 29(7):A-342.

Huelsenbeck, J.P. and P.J. Wagner.  1996.  Stratigraphic data and estimates of phylogenies:  contrasting the efficiency of different methods using simulations.  Sixth North American Paleontological Convention Abstracts of Papers.  p. 184.

Wagner, P.J.  1996.  Biases in diversity patterns interpolated from cladograms.  Geological Society of America, Abstracts with Programs 28(7):A-250.

Wagner, P.J.  1996.  Diversification and paraclade survivorship in morphospace.  Sixth North American Paleontological Convention Abstracts of Papers.  p. 410.

Wagner, P.J.  1995.  Morphologic diversification among rostroconch molluscs.  Geological Society of America, Abstracts with Programs 27(7):A-52.

Wagner, P.J.  1994.  Contrasting active and passive trends: a phylogenetic and morphometric analysis of early gastropods.  Geological Society of America, Abstracts with Programs 26(7):A-52

Wagner, P.J.  1993.  Temporal patterns of morphologic disparity among early Paleozoic "archaeogastropods."  Geological Society of America, Abstracts with Programs 25(6):A-51.

Wagner, P.J. and D.H. Erwin.  1992.  Cladograms as tests of speciation hypotheses.  Geological Society of America Abstracts with Programs 24(7) : A139.

Wagner, P.J.  1992.  Phylogenetic versus taxonomic diversity patterns among Early Paleozoic archaeogastropods.  Geological Society of America Abstracts with Programs 24(7) : A-46.

Wagner, P.J.  1992.  Phylogenetics of the Archaeogastropoda of the Early Paleozoic. Fifth North American Paleontological Convention Abstracts of Papers.  p. 300.

Wagner, P.J.  1990.  Phylogenetics of the Lophospiridae (Pleurotomarioidea : Gastropoda) of the Ordovician and Silurian.  Geological Society of America Abstracts with Programs 22(7) : A221.

Presentations at Invited Symposia

Darwin 2009 (SUNY, 11/09)
Testing Macroevolutionary Hypotheses of Diversification: Approaches and Perspectives (Society of Integrative and Comparative Biology Annual Meeting, San Antonio 1/08)
Perfect phylogeny and Other Problems: Compatibility Methods in Systematics (Biennieal Conference of the Systematics Association, Cardiff, 8/05)
Molluscan Phylogeny Symposium (World Congress of Malacology, Perth 7/04)
The Study of Sequences in Natural Sciences (Society of Integrative and Comparative Biology Annual Meeting, New Orleans 1/04)
Approaches to Reconstructing Phylogeny (Lyell Meetings, London, 6/02)
Major Evolutionary Radiations (Society of Systematic Biology Meetings, 6/00).
Beyond Phylogeny Reconstruction: Tree-Based Analyses in Paleontology (Geological Society of America, 10/99)
Bridging Temporal Scales in Malacology: Uniting the Living and the Dead (World Congress of Malacology, 7/98)
Stratigraphy and Phylogeny (Society of Vertebrate Paleontology, 9/97)
Traditional versus Phylogenetic Classifications in Malacology  (American Malacological Union, 6/97)
Morphospace Concepts in Paleobiology (North American Paleontolological Convention, 6/96)
Molluscan Speciation (American Malacological Union, 6/93)
Speciation and the Fossil Record (Geological Society of America, 10/92)
Phylogeny and Classification of Gastropods  (American Malacological Union, 8/92)

Invited Seminars

Compatibility: some new uses for an old metric.  (U. Cincinnati, 4/08).
Relative Abundance Distributions in the fossil record and their implications for major extinction events (U. New York, Buffalo, 4/07)
Relative Abundance Distributions in the fossil record and their implications for major extinction events (Cambridge University, 1/07)
Likelihood tests of macroevolutionary scenarios: examples with gastropods (Smithsonian, 6/04)
Relative abundance distributions and sampled richness (NCEAS, Santa Barbara, 1/04)
Hypothesis testing with likelihood: general relationships and speciation modes (S.U.N.Y. 12/03)
Likelihood tests of general phylogenetic hypotheses: an example with bellerophont molluscs (U. Leipzig. 3/03)
They meant to do that: dissecting patterns of gross convergence among early gastropods (U. Chicago, 2/02).
Effects of species distribution curves on sampled richness (U. New Mexico, 10/01). 
Phylogeny likelihood given morphologic data (U. Chicago, 2/98).
Biases in diversity patterns implied by model phylogenies (U. Illinois, Chicago, 2/97; U. Arizona, 4/97).
Decreasing rates of morphologic evolution among early gastropods (U. C., Berkeley, 11/94).