Analyzing and attributing natural selection to particular sources

26-27 January 2009


Ben Ridenhour (hiw2 (at) cdc.gov) US Centers for Disease Control & Prevention, Atlanta, USA


This course will focus on data analysis procedures for estimating natural selection in study populations. In particular, we will concentrate on the fundamental statistics underlying selection analyses (linear regression techniques in particular).

The final objective will be to understand how to perform a 'selective source analysis' , so that selection pressure can be attributed to a particular aspect of the biotic or abiotic environment.


The course time will be divided between lecture, discussion, and practicals. We will be using the statistical package R to perform analyses; knowledge of using R will be helpful but not required. Students should also have a basic understanding of natural selection and linear regression.

Upon completion, students should feel comfortable thinking critically about selection analysis and have confidence in their ability to perform selection analysis or selective source analysis using standard statistical packages such as R.

pre-course assignment

Reading of the following publications:

1) The contribution of parasitism to selection on floral traits in Heuchera grossulariifolia
Nuismer SL, Ridenhour BJ
Journal of Evolutionary Biology, 2008, 21 (4), 958-965 (Nuismer_JEB2008.PDF)

2) Identification of selective sources: Partitioning selection based on interactions
Ridenhour BJ
American Naturalist, 2005, 166 (1), 12-25 (Ridenhour_AN2005.PDF)

3) Reciprocal selection at the phenotypic interface of coevolution
Brodie ED, Ridenhour BJ
Integrative and Comparative Biology, 2003, 43 (3), 408-418 (Brodie_ICB2003.PDF)

4) The measurement of selection on correlated characters
Lande R, Arnold SJ
Evolution, 1983, 37 (6), 1210-1226 (LANDE_E1983.PDF)

To discuss those publications, a seminar will be organised on 15 January 14.00-17.00:


  • Every participant reads all publications in advance, and thinks of questions.
  • Each publication is presented by at least two students, who team up to prepare a powerpoint presentation of ca 10-15 minutes
    (e.g.: what is the question addressed in the study, which methods and approaches are used or presented, for which type of applications is this suitable, which examples are given, which questions remain unanswered, etc).
    Preparation happens in groups before the course.
  • After each presentation, all participants discuss the publication (ca 15 minutes discussion).

Persons in charge: Anne-Marie Labouche and Giorgina Bernasconi

Choices of publications: please contact Anne-Marie Labouche (anne-marie.labouche (at) unine.ch)

general information

Dates:  Monday 26 and Tuesday 27 January 2009 (pre-seminar on 15 January 2009)

Schedule: 8.55 - 17.00

Location: Université de Neuchâtel, Faculté des sciences, UniMail, building C (Animalerie), room 001. Practicals: Millenium computer room

Credit points: 1.5 credit point (Research tools)

Evaluation: Active participation including personal work as described and pre-seminar attendance

Information: Please contact Dr. Ben Ridenhour or the  NCCR education officer Dr. Christiane Bobillier (for administrative matters)

Travel expenses: NCCR Doctoral programme "Plants and their Environment" participants are eligible for reimbursement of incurred travel expenses by train (half-fare card, and 2nd class). Please send the original tickets (no copies, except for the general abonnement) with this form (17 ko, pdf document) to Dr. Christiane Bobillier.  No reimbursement for bus, taxi or car travel expenses will be paid.


This course is opened to all Ph.D. students. However, priority is given to doctoral programme "Plants and their Environment" participants. This course is free.

Minimum number of participants: 10, maximum: 20.

Registration through the web only: closed.

Deadline: 12 January 2009