Holden, Anna main content.

Anna Holden

A woman, Anna Holden, looking at the camera, with a large butterfly or moth perched on her open palm.

PhD Student, Richard Gilder Graduate School
PhD Student, Richard Gilder Graduate School


  • Ph.D. in Comparative Biology, Richard Gilder Graduate School at the American Museum of Natural History, Expected: September 2018.
  • M.A. Museum Studies (Harvard Extension School), Harvard University, 2006.
  • Nonprofit Management Courses (Harvard Extension School), Harvard University, 2006–2007
  • B.A. Combined Studies in Biology and Studio Arts, Hampshire College, 2000
  • Courses towards BA, The School of the Museum of Fine Arts, Boston.

Research Interests

The Rancho La Brea Tar Pits, one of the world’s richest and most important Ice Age fossil localities, is particularly celebrated for its extinct large mammal fauna, and bird collection. This locality's lesser known insect collection is equally vast. These fossils are comprised of original, asphalt-impregnated material; such three-dimensionality and rarely preserved structural details provide a means for securely identifying species. Many researchers have observed that virtually all Quaternary insects are identical to modern species, which has stimulated a resurgent interest in their systematics and use as paleoenvironmental indicators. The Rancho La Brea insect collection provide significant paleoenvironmental inferences when specimens can be confidently identified and certain entrapment events establish a clear provenance; their specific life-cycles, climate restrictions, and constraints to the local environs offer critical details to the changing landscape and climate in and around Rancho La Brea. Novel methods will be used to unlock the storehouse of data that such fossil insects can offer. Projects will focus on 1) Indicator insects and insect-plant interactions that offer rich paleoenvironmental data based on sufficient modern documentation of their life-cycles, climate restrictions, and distribution 2) Multiple radiocarbon and stable isotopic anlayses of insect material; while collagen dating of the bones of large mammals from Rancho La Brea has shed light on their diet, ecology, and taphonomy, insects are often superior paleoenvironmental indicators in terms of establishing precise data points for climate fluctuations and entrapment periods 3) The synthesis of data sets to establish the conditions prevailing in the vicinity of Rancho La Brea during the Late Pleistocene extinction event.


In Preparation

Holden, A. R., and Southon, J. A paleoenvironmental and taphonomic study of southern California at ~44,000 years ago based on a rare fossil insect assemblage from the Rancho La Brea Tar Pits. In advanced preparation.

Holden, A. R. “Recent Advances in the Study of Rancho La Brea’s Quaternary Insect Collection.” In advanced preparation.

Publication Under Review

Holden A. R, Angus, R., Barclay, M. (2017) “Nearctic origins of a previously considered invasive species, Necrobia violecea (Coleoptera: Cleridae) to North America.” Under Review. Coleopterists' Bulletin.


Holden, A. R., Southon, J. R., Will, K., Kirby, M. E., Aalbu, R. L., Markey, M.J .  “A 50,000 year insect record from Rancho La Brea, southern California: Insights into fossil deposition and past climate.” Quaternary Science Reviews, 168: 123-136, July 15, 2017.


Holden, A. R., and Southon, J.R. “ Radiocarbon dating and stable isotopic analysis of insect chitin from the Rancho La Brea Tar Pits, southern Claifornia.” Radiocarbon, 58(01), 99-113, March 2016.


Holden, A. R., Erwin, Diane M., Schick, K., N. and Gross, J. “Late Pleistocene galls from the La Brea Tar Pits; Implications for cynipine wasp and native plant distribution in southern California.” Quaternary Research, 84(3), 358-367, November 2015.


Holden, A. R., Koch, J. B., Griswold, T., Erwin, D. M., and Hall, J. “Leafcutter bee nests and pupae from the Rancho La Brea Tar Pits of southern California: Implications for understanding the paleoenvironment of the Late Pleistocene.” PLoS One, April 9, 2014.


Holden, A. R., Harris, J. M. and Timm, R. M. "Paleoecological and taphonomic implications of insect-damaged Pleistocene vertebrate remains from Rancho La Brea, southern California." PLoS One, July 3, 2013.

Holden, A. R. and Harris, J. M. "Late Pleistocene Coleopteran Galleries in Wood from the La Brea Tar Pits: Colonization of Juniper by Phloeosinus Chapuis (Curculionidae: Scolytinae) and Buprestidae." The Coleopterists Bulletin 67(2):155-160, 2013.