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Adventures of a Mathematical Biologist

Editor's note: Dr. Castillo-Chavez will be lending his talents in a MiSciNet column for students beginning January 2004. The focus will be providing students with information on how to navigate through college and beyond.

My name is Carlos Castillo-Chavez and I was born in Mexico City about half a century ago. Although my mother, Estela Chávez Cárdenas, only finished the fourth grade, both she and my father, Carlos Castillo Cruz, initiated and fed my passion for education. While my mother stayed busy raising four children all born about a year apart, my father completed physics and engineering degrees while holding a full-time job to support the family. My strong upbringing became the backbone for my family. My loving wife, Nohora M. Londono DeCastillo, and I have three wonderful children, Carlos William, Melissa Ann, and Gabriela Citlalli.

The Early Years

As a youngster in elementary and junior high schools, I excelled in all academic subjects. I was especially talented with numbers, but I never thought about becoming a mathematician or a scientist. In fact, I had a strong desire to become either an actor or a hotel manager. However, after the 2 October 1968 student massacre at Tlatelolco, I lost interest in school, but regained my love of knowledge sometime later.

In 1974 I immigrated to Wisconsin where I held a few nonacademic jobs--including brief stints as a material handler at a cheese factory and a bank clerk. I enrolled at the University of Wisconsin, Stevens Point (UWSP) in 1975, where I majored in Spanish literature and mathematics. It only took me three semesters and a summer to graduate because they gave me credit for being fluent in Spanish and credit for completed coursework in Mexico.

I completed my bachelor's degree in 1976 thanks to the urgent financial aid package arranged for me by Lee Dreyfus, chancellor of UWSP. I walked into his office and told him, "I need $400 or I will not graduate." He said, "No problem, go and talk to Mr. X and everything will be fine." I said, "I already did and he said that it was not possible." Dr. Dreyfus, who later became the governor of Wisconsin, then said, "Tell Mr. X that the chancellor wants it done. Tell him to write the necessary letters, which should then be sent to me for revision. You will graduate." Thanks to Dr. Dreyfus, I did graduate being only one of two full-time Latino students at UWSP at that time.

I completed a master's degree in mathematics in 1977 at the University of Wisconsin, Milwaukee (UW-Milwaukee) and began their Ph.D. program. After a serious disagreement with my advisor, I had to quit. UW-Milwaukee Professor Gilbert Walter helped me through this difficult time and got me back into a Ph.D. program in 1980. In December of 1984, after 3 and 1/2 years at UW-Madison and one at the University of Maryland, I completed my Ph.D. in applied mathematics at UW-Madison. I had been teaching at the University of Tulsa in Oklahoma (1984-85) during my doctoral work, but eventually moved there after the Ph.D. I accepted a postdoctoral position in the department of ecology and evolutionary biology at Cornell University in 1985, and in 1988 I joined Cornell University as an assistant professor of biomathematics. I was promoted to associate in 1991 and to a full professorship in 1997.

Research Interests

My research exists at the interface of disease and social dynamics. I have carried out joint research on HIV/AIDS, tuberculosis, influenza, dengue, SARS, sexually transmitted diseases, and foot and mouth disease. I am currently collaborating on issues that are relevant to our nation's homeland security. For example, I am involved in efforts to evaluate the potential impact of the deliberate release of biological agents on mass transportation systems as well as the potential impact of the spread of fanatic behaviors on local cultural norms.

My research also touches on questions at the interface of ecology and evolutionary biology. I have co-authored several joint publications on the role of dispersal and disease on life-history evolution. I have also begun to develop a research program on the dynamics of addiction at the population level (alcohol, smoking, and even the ecstasy drug). My research has resulted in over 100 publications, a textbook, and five edited volumes including a volume on bioterrorism that has just been published in the SIAM Series, Frontiers in Applied Mathematics .

I currently have nine graduate students, with the following being doctoral candidates: Gerardo Chowell-Puente, Miriam Nuno, Ariel Cintron-Arias, Fabio Sanchez, and Steve Tennenabum. David Murillo, Karen Rios-Soto, Griselle Torres-Garcia, and Reynaldo Castro are the other hard-working graduate students in my lab.

Honors and Awards

I have been the recipient of various awards including two White House Awards (1992 and 1997), a QEM Giant in Science Mentoring Award (2000), Society for Advancement of Chicanos and Native Americans in Science (SACNAS) distinguished senior scientist award (2001), and the first Richard Tapia Award (2003). In addition, I received a Presidential Award for Excellence in Science, Mathematics and Engineering Mentoring (1997) for the work that I carried out at the Mathematical and Theoretical Biology Institute (MTBI). I was also named distinguished alumni by the UWSP Alumni Association (1999), Profesor Plenario by the Universidad de Belgrano (Argentina, 1996), and held a Cátedra Patrimonial at the Institute of Applied Mathematics (IIMAS, UNAM, México) in 1998. I am the current holder (2003) of the Ulam Scholar position at the Center for Nonlinear Dynamics at Los Alamos National Laboratory in New Mexico.

The Mathematical and Theoretical Biology Institute

In collaboration with Herbert Medina (Loyola Marymount University), and with the strong support of William Yslas Vélez (SACNAS president at the time), I established MTBI in 1996. MTBI (now co-directed by Steve Wirkus) supports and fosters research activities primarily among underrepresented minority undergraduate students who are enrolled at nonselective U.S. universities. During the regular academic year, MTBI also mentors these students who carry out research in the mathematical or statistical sciences.

MTBI has trained over 200 undergraduate students and over 20 graduate students in the mathematical and statistical sciences for the past eight summers. Over 50% of MTBI's alumni are currently enrolled in graduate programs across the nation--most of them with long-term fellowship support. MTBI has been supported by grants from the National Science Foundation, the National Security Agency, the Sloan Foundation, and the Office of the Provost at Cornell University.

A New Chapter

On 1 January 2004, after 18 years at Cornell University, MTBI and I will move to Arizona State University (ASU) where I will become the first holder of the Joaquin Bustoz Jr. professorship in mathematical biology. The Office of the Provost at ASU, Milton Glick, will become the main supporter of MTBI and its mission. The late Joaquin Bustoz Jr. personally recruited me for this position before he died last summer. Although Dr. Bustoz will be sorely missed, I will do my best to live up to the high level of excellence he set for the department and faculty. I am looking forward to this new chapter in my life at ASU.

Carlos Castillo-Chavez, Ph.D., is a Joaquin Bustoz Jr. Professor of Mathematical Biology at Arizona State University and my be reached at or at