Bryan Nicholas Danforth Department of Entomology Comstock Hall Cornell University Ithaca, NY 14853-0901 Phone: 607-255-3563 / FAX: 607-255-0939 Email: bnd1@cornell.edu Web: http://www.entomology.cornell.edu/Faculty_Staff/Danforth

Academic Rank:

Associate Professor

Appointment

50% Research - 50% Teaching

Education

BS zoology, Duke University, Durham, NC, 1983.
MS entomology, University of Kansas, Lawrence, KS, 1987. Advisor: C.D. Michener.
PhD entomology, University of Kansas, Lawrence, KS, May, 1991. Advisor: C.D. Michener.

Research Interests and Projects Currently Underway

I. Phylogeny, evolution, and historical biogeography of the short-tongued (i.e., primitive) bees.

The "short-tongued" bees include the families Colletidae, Stenotritidae, Andrenidae, Halictidae and Melittidae. These families are presumed to be the basal, or primitive, bee families from which the long-tongued bees (the families Apidae and Megachilidae) arose. At present, we have a very poor understanding of the family-level relationships among these groups (see figure below).

Research in my lab focuses on resolving the phylogeny of short-tongued bee families, subfamilies, tribes, and genera. We use a combination of morphological data and single-copy nuclear gene sequences (from genes such as DDC, PEPCK, wingless, opsin, and EF-1α). Resolving the phylogeny of these groups is important for understanding early bee evolution, reconstructing the historical biogeography of the bees, and developing a more stable classification of the bees. However, the earliest diversification of the bees occurred long ago (early to mid-Cretaceous), so resolving these relationships is not easy and will require a substantial amount of data (both morphological and molecular). This work is funded by a collaborative NSF grant to Sedonia Sipes (http://www.science.siu.edu/plant-biology/Faculty/sipes/index.html) and myself.

In collaboration with Sedonia Sipes and Sean Brady (now at Smithsonian Institution), we are using the available fossil data from bees, large, single copy nuclear gene data sets (described above), and recently developed Bayesian methods to estimate the antiquity of bees. These results will give us new insights into the early evolution of bees, and the interactions between bees and angiosperm plants in the early stages of bee evolution.

Recent work with Sean Brady has involved characterization of an intron in the F1 copy of EF-1α that is restricted to the bee family Colletidae. This unique intron provides compelling evidence supporting colletid monophyly and exclusion of the Stenotritidae from the Colletidae, and provides the first use of a macromutation in higher-level bee phylogeny.

(Click on image for a larger view)

II. Phylogeny and evolution of the halictid bees.

The bee family Halictidae includes over 4000 species of bees. While they are commonly maligned as "morphologically monotonous" bees, this family is a key one for understanding higher-level bee phylogeny (see above) as well as for understanding bee social evolution. Within the halictid bees there are approximately 1000 eusocial species in four genera: Halictus, Lasioglossum, Augochlora, and Augochlorella. Eusociality has arisen multiple times within the halictid bees (we estimate three independent origins). By combining information on social evolution and halictid phylogeny, we are attempting to reconstruct the history of social evolution in this group. See Danforth (2002) and the cladogram below for more information on this.

Among the more poorly known groups of halictid bees are the predominantly African genera, including Thrincostoma (and Parathrinchostoma), Zonalictus, Chaetalictus, Patellapis, and Lomatalictus. An ongoing project (funded by the National Geographic Society) in collaboration with Kenneth Walker (Australia), Connal Eardley (South Africa), and Laurence Packer (Canada) aims to understand more about the social evolution and phylogenetic affinities of these predominantly African groups. Our preliminary results indicate some fascinating biogeographic patterns.

Recently, Adam Pearson (Cornell '03) and Sean Brady (now at Smithsonian Institution) have been using the limited fossil data on halictid bees, single-copy nuclear gene data sets based on wingless, opsin, and EF-1α to estimate the antiquity of eusociality in halictid bees. These analyses are providing some surprising results!

(Click on image for a larger view)

III. Phylogeography of bees.

Bees show a wide range of geographic distributions from species which occur only on isolated mountain tops in southern Arizona and northern Mexico (such as Mexalictus arizonensis) to those that range widely across the Holarctic region (such as Halictus rubicundus, which occurs in Europe and across North America). The phylogeographic patterns evident in bee species have rarely been examined using mitochondrial DNA sequence data, but preliminary investigations of several species indicate fascinating patterns. In collaboration with Sheryl Soucy we investigated the phylogeographic patterns in Halictus rubicundus collected in Europe and across N. America. It appears that high elevation sites in western N. America form a monophyletic group that is most closely related to populations in Europe, consistent with dispersal from Eurasia into N. America via the Bering Land Bridge during the Pleistocene. Similar studies are underway on Mexalictus arizonensis (in Arizona) and Lasioglossum leucozonium (in Europe).

IV. Population genetics and ecology of desert bees.

Bees show an unusual biogeographic pattern: greatest species diversity in the arid and semi-arid region of the world where rainfall is both limited and unpredictable. Areas of highest bee diversity include the deserts of the American southwest, Mediterranean regions, arid regions of South America, and Australia. Why bees show such diversity in harsh, unpredictable environments is a mystery. We are investigating gene flow, emergence phenology, and life history patterns in order to understand the role seasonality has played in bee diversification. Results from one desert bee, Perdita portalis, indicate that larvae emerge in response to high humidity (rainfall-induced emergence), that overwintering larvae "hedge their bets" by not emerging even under optimal conditions, and that among-population gene flow is limited (Fst=0.19) (Danforth 1999, Danforth et al. 2003). Such patterns are consistent with the view that rainfall-induced emergence may lead to allochronic speciation in desert habitats. We suspect that heterogeneous and unpredictable rainfall patterns in arid regions may be an important speciation mechanism in desert bees. Such studies are now being extended to other desert bee species, and we (Robert Minckley and I) have plans to submit an NSF grant on this topic in the future.

V. Pollination biology of bees in NY state

Many people would be surprised to learn that in NY state alone there are over 450 species of bees. In terms of global diversity, we have six of the seven bee families in New York state (the only bee family not in New York state is the Stenotritidae, a family restricted to Australia), 10 of the 20 currently recognized bee subfamilies, and 47 of the 425 genera of the world. The fauna of New York state could best be described as typical of a temperate, northern Hemisphere bee fauna. In fact, in terms of genera, the northern parts of the United States (including New York state) are not unlike the bee fauna of Western Europe. Our most common (and speciose) genera are Andrena (112 spp.), Lasioglossum (68 spp.), Nomada (54 spp.), Sphecodes (26 spp.), Megachile (21 spp.), Colletes (20 spp.), Osmia (19 spp.), Hylaeus (16 spp.), Melissodes (14 spp.), Bombus (14 spp.), and Coelioxys (13 spp.).

Native bees provide an extremely important service as pollinators of native and agricultural plants. For example, apple production comprises a >$100 million industry in New York state, and a large number of native bee species (primarily in the genera Andrena, Osmia, and Bombus) contribute to apple pollination. I am interested in developing projects on the importance and management of native pollinators in NY state.

For more information on the bees of NY state, see the following web site:

http://www.nybiodiversity.org/summaries/bees/index.html

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Undergraduate And Graduate Student Research Projects

Undergraduate and graduate students are involved in a diversity of projects related tobee phylogeny, evolution, pollination biology, conservation, and biogeography. Karl Magnacca has nearly completed his PhD research on the only native bees in the Hawaiian Islands (the colletid genus Hylaeus). His studies combine phylogeny, pollination biology, conservation and biogeography. John Ascher recently completed his PhD thesis on the phylogeny and evolution of the bee family Andrenidae based on a combined analysis of morphological and molecular data. His results provide fascinating insights into the historical biogeography of the andrenid bees. Chung-Ping Lin recently completed a PhD on the evolution and social behavior of the tree-hoppers (Membracidae). Eduardo Almeida has recently started his PhD on the phylogeny and historical biogeography of the bee family Colletidae. Colletids are a fascinating group which may represent one of the most primitive bee families. Colletids have a Gondwanan biogeographic distribution, with subfamilies, tribes and genera distributed primarily in the southern continents of Australia, South America and Africa.

Recent undergraduates in the lab have worked on projects related to bee phylogeny. Adam Pearson ('03) developed single-copy nuclear gene data sets (wingless and opsin) for resolving relationships in the bee family Halictidae. Adam's results provide new insights into the antiquity of eusociality in the halictid bees. Allison Novick ('06) is currently working on developing a 28S data set for the short-tongued bees and Alex Swanson ('05) is developing a molecular and morphological data set for the halictid subfamily Nomiinae.

Graduate student projects could focus on any aspects of the biology, systematics, evolution or conservation of bees and their relatives.

John Ascher	Karl Magnacca	From Left to Right: Allison Novick, Sean Brady, Eduardo Almeida

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Graduate & Post-Doctoral Associates (past and present)

John S. Ascher (email: ja41@cornell.edu)
Current address: Department of Invertebrate Zoology
American Museum of Natural History
Central Park West @ 79^th St.
New York, NY 10024-5192

Karl N. Magnacca (email: knm5@cornell.edu)
Current address: Hawaii Volcanos National Park
PO Box 11, Hawaii
National Park, HI 96718
E-mail: see above.
Phone: 808-985-6073

Chung-Ping Lin (email: cl135@cornell.edu)
Current address: Division of Biological Sciences
University of Missouri
Columbia, MO 65211
E-mail: linchung@missouri.edu
Phone 573-882-4189

Sean Brady (email: sb323@cornell.edu)
Current address:Department of Entomology
MRC 165
National Museum of Natural History
Smithsonian Institution
Washington, DC 20560

Sedonia Sipes
Current address: Department of Plant Biology
Life Science II 420
Mailcode: 6509
Southern Illinois University Carbondale
Carbondale, IL 62901-6899
Phone: 618-453-3213
Fax: 618-453-3441
E-mail: ssipes@plant.siu.edu
Web site: http://www.science.siu.edu/plant-biology/Faculty/sipes/index.html

Sheryl Soucy
Current address: Department of Entomology/Bohart Museum
University of California
Davis, CA 95616
E-mail: slslubell@ucdavis.edu

Eduardo Almeida (email: eaa28@cornell.edu)
Currently at Cornell.

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Teaching Activities

Entom 201 -- Alien Empire: Bizarre Biology of Bugs (even springs)
Insects are the most abundant and diverse animals on earth. This course will explore the bizarre biology of insects by examining their evolutionary history, anatomy, development, feeding habits, life-history strategies, behavior, and their interactions with humans (both positive and negative) through history.  Optional field trips and one open lab will provide hands-on opportunities for examining these amazing animals.

Entom 322 -- Insect Comparative Morphology
This course provides a detailed introduction to the external and internal anatomy of insects. Lectures introduce basic concepts in insect morphology, such as the organization of the insect body plan and organ systems, functional morphology, homology, phylogeny, modularity, and development. The laboratory portion of the course introduces students to the basic methods of insect microdissection, specimen preparation, and scientific illustration. High-quality, publishable illustrations are produced based on student art-work.  The lab manual is available online at http://www.entomology.cornell.edu/Faculty_Staff/Danforth/322Lab.html.

Entom 635 -- Insect Molecular Systematics
Analysis of DNA sequence variation can provide a powerful tool for resolving problems in insect systematics, from species level taxonomic decisions to higher level (ordinal) relationships. This course will introduce students to the basic methods of insect molecular systematics, including DNA extraction, gel electrophoresis, PCR, DNA purification, and DNA sequencing (manual and automated). Results will be analyzed using available computer programs. Students are encouraged to collect preliminary data for thesis or post-doctoral research.

"The Bee Course" --
Taught annually at the Southwestern Research Station, Portal, AZ. For more infomation contact Jerome Rozen Jr. (email: rozen@amnh.org) or visit the web site: http://research.amnh.org/invertzoo/beecourse

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Publications

Refereed publications (in reverse chronological order):

Danforth, B.N., S.G. Brady, S.D. Sipes & A. Pearson (in prep.). Dating the antiquity of eusociality in halictid bees.

Ascher, J.S., B.N. Danforth, J.G. Rozen, Jr. (in prep.). Phylogeny and historical biogeography of the bee family Andrenidae based on morphological and molecular data. Systematic Entomology

Danforth, B.N., S.G. Brady, S.D. Sipes & A. Pearson (in review). Single copy nuclear genes recover Cretaceous age divergences in bees with high bootstrap support and posterior probabilities. Syst. Biol.

Brady, S.G. & B.N. Danforth (in review). Unique intron insertion in elongation factor-1α (EF-1α) supports monophyly of colletid bees (Hymenoptera: Colletidae). Mol. Biol. Evol.

Lin, C.P. & B.N. Danforth (in press). How do insect nuclear and mitochondrial gene substitution patterns differ? Insights from Bayesian analyses of combined data sets. Mol. Phylo. Evol. [pdf file available]

Danforth, B.N., S. Ji, & L.J. Ballard. 2003. Gene flow and population structure in an oligolectic desert bee, Macrotera (Macroteropsis) portalis (Hymenoptera: Andrenidae). J. Kansas Entomological Society 76(2): 221-235.

Danforth, B.N., L.Conway, & S. Ji. 2003. Phylogeny of eusocial Lasioglossum reveals multiple losses of eusociality within a primitively eusocial clade of bees (Hymenoptera: Halictidae). Syst. Biol. 52(1): 23-36. [pdf file available]

Danforth, B.N. 2002. Evolution of sociality in a primitively eusocial lineage of bees. Proc. Natl. Acad. Sci. (USA) 99(1): 286-290. [pdf file available]

Soucy, S.L. & B.N. Danforth. 2002. Phylogeography of the socially polymorphic sweat bee Halictus rubicundus (Hymenoptera: Halictidae). Evolution 56 (2): 330-341. [pdf file available]

Ascher, J.S., B.N. Danforth, S. Ji. 2001. Phylogenetic utility of the major opsin in bees (Hymenoptera: Apoidea): a reassessment. Mol. Phylo. Evol. 19: 76-93.[pdf file available]

Danforth, B.N. & S. Ji. 2001. Australian Lasioglossum + Homalictus form a monophyletic group: resolving the "Australian enigma." Syst. Biol. 50(2): 268-283.[pdf fileavailable]

Tilmon, K.J., B.N. Danforth, M.P. Hoffmann, W.H. Day. 2000. Determining parasitoid species composition in a host population: a new molecular approach. Ann. Entomol. Soc. America 93(3): 640-647.

Danforth, B.N. 1999. Phylogeny of the bee genus Lasioglossum (Hymenoptera: Halictidae) based on mitochondrial cytochrome oxidase. Syst. Entomol. 24(4): 377-393.

Danforth, B.N., H. Sauquet, L. Packer. 1999. Phylogeny of the bee genus Halictus (Hymenoptera: Halictidae) based on parsimony and likelihood analyses of nuclear EF-1α sequence data. Molecular Phylogenetics and Evolution 13(3):605-618. [pdf file available]

Danforth, B.N. 1999. Emergence dynamics and bet hedging in a desert bee Perdita portalis. Proc. Royal Society of London 266:1985-1994. [pdf file available]

Danforth, B.N. & C. A. Desjardins. 1999. Male dimorphism in Perdita portalis (Hymenoptera: Andrenidae) has arisen from preexisting allometric patterns. Insectes Sociaux 46:18-28.

Danforth, B.N. & W.T. Wcislo 1999. Two new and highly apomorphic species of the Lasioglossum subgenus Evylaeus (Hymenoptera: Halictidae) from Central America. Ann. Entomol. Soc. Am. 92:624-630.

Danforth, B.N, P. Mitchell & L. Packer. 1998. Mitochondrial DNA differentiation between two cryptic Halictus species. Ann. Entomol. Soc. Am. 91:387-391.

Danforth, B.N. & S. Ji. 1998. Elongation factor-1α occurs as two copies in bees: Implications for phylogenetic analysis of EF-1α sequences in insects. Mol. Biol. Evol. 15(3):225-235.

Wcislo, W.T. & B.N. Danforth. 1997. Secondarily solitary: the evolutionary loss of social behavior. Trends Ecol. Evol. 12:468-474.

Danforth, B.N. 1996. Phylogenetic analysis and taxonomic revision of the Perdita subgenera Macrotera, Macroteropsis, Macroterella and Cockerellula (Hymenoptera: Andrenidae). Kansas Science Bulletin 55(16):635-692.

Danforth, B.N. & C.R. Freeman-Gallant. 1996. DNA fingerprinting and the problem of non-independence among pairwise comparisons. Mol. Ecol. 5:221-227.

Danforth, B.N., J.L. Neff, P. Barretto-Ko. 1996. Nestmate relatedness in a communal bee, Perdita texana (Hymenoptera: Andrenidae), based on DNA fingerprinting. Evolution50(1):276-284.

Danforth, B.N. 1994. Taxonomic review of Calliopsis subgenus Hypomacrotera (Hymenoptera: Apoidea) with special emphasis on the distributions and host plant associations. Pan-Pacific Entomol. 70:283-300.

Danforth, B.N. & P.K. Vissher. 1993. Dynamics of a host-cleptoparasitic relationship: parasitism of Calliopsis pugionis (Hymenoptera: Andrenidae) by Holcopasites ruthae (Hymenoptera: Anthophoridae). Ann. Entomol. Soc. Am.86:833-840.

Visscher, P.K. & B.N. Danforth. 1993. Nesting, foraging and investment sex ratio in Calliopsis pugionis (Hymenoptera: Andrenidae). Ann. Entomol. Soc. Am.86:822-832.

Danforth, B.N. & J.L. Neff. 1992. Male polymorphism and polyethism in Perdita texana (Hymenoptera: Andrenidae). Ann. Entomol. Soc. Am. 85:616-626.

Neff, J.L. & B.N. Danforth. 1992 (1991). The nesting and foraging behavior of Perdita texana Cresson (Hymenoptera: Andrenidae). J. Kansas Entomol. Soc. 64:394-405

Norden, B.B., K.V. Krombein & B.N. Danforth. 1992. Taxonomic and bionomic notes on Perdita (Hexaperdita) graenicheri. Journal of Hymenoptera Research 1:107-118.

Snelling, R.R. & B.N. Danforth. 1992. A review of the Perdita subgenus Macrotera (Hymenoptera: Andrenidae). Contributions in Science, Natural History Museum of Los Angeles County 436:1-12.

Danforth, B.N. 1991. Female foraging and intranest behavior of a communal bee, Perdita portalis Timberlake (Hymenoptera: Andrenidae). Ann. Entomol. Soc. Am. 84:537-548.

Danforth, B.N. 1991. The morphology and behavior of dimorphic males in Perdita portalis (Hymenoptera: Andrenidae). Behav. Ecol. Sociobiol. 29:235-247.

Danforth, B.N. 1990. Provisioning behavior and the estimation of investment ratios in a solitary bee, Calliopsis (Hypomacrotera) persimilis (Cockerell) (Hymenoptera: Andrenidae). Behav. Ecol. Sociobiol. 27:159-168.

Danforth, B.N. 1989. The evolution of hymenopteran wings: the importance of size. J. Zool., London 218:247-276.

Danforth, B.N. 1989. Nesting behavior of four species of Perdita (Hymenoptera: Andrenidae). J. Kansas Entomol. Soc. 62:59-79.

Danforth, B.N. & C.D. Michener. 1988. Wing folding in the Hymenoptera. Ann. Entomol. Soc. Amer. 81:342-349.

Schaaper, R., B. Danforth & B. Glickman. 1986. Mechanisms of spontaneous mutagenesis: an analysis of the spectrum of spontaneous mutations in the E. coli lac I gene. J. Mol. Biol. 189:273-284.

Schaaper, R., B. Danforth & B. Glickman. 1985. Rapid repeated cloning of mutant lac repressor genes. Gene 39:181-189.

Letters:

Danforth, B.N. & J. Ascher (1999). Flowers and insect evolution: reply to Farrell. Science 283(5399):143. [http://www.sciencemag.org/cgi/content/full/283/5399/143a]

Wcislo, W.T. & B.N. Danforth. 1998. Reply to Scharff & Burda. Trends Ecol. Evol. 13:199.

Book chapters (in reverse chronological order):

Aquadro, C.F. W.A. Noon, D.J. Begun & B.N. Danforth. 1998. RFLP analysis using heterologous probes. In: A.R. Hoeltzel. Molecular Genetic Analysis of Populations. A Practical Approach (pp. 151-200). IRL Press at Oxford University Press, Oxford.

Danforth, B.N & G.C. Eickwort. 1997. The evolution of social behavior in the augochlorine sweat bees (Hymenoptera: Halictidae) based on a phylogenetic analysis of the genera. In: B. J. Crespi, & J.C. Choe. The Evolution of Social Behavior in Insects and Arachnids (pp. 270-292). Cambridge University Press.

Books:

Michener, C.D., R.J. McGinley & B.N. Danforth. 1994. The Bee Genera of North and Central America (Hymenoptera: Apoidea). Smithsonian Institution Press, Washington, DC. vii+209pp.

Extension publications/web sites:

Danforth, B.N. & C.M. Marshall. 2003. Insect morphlogy meets the WWW. Amer. Entomol. 48(4): 197-199.

Danforth, B.N. & K.N. Magnacca (2002). Bees of New York State. NY State Biodiversity Clearinghouse, New York State Biodiversity Project and New York State Biodiversity Research Institute. [http://www.nybiodiversity.org/summaries/bees/index.html]