How to simplify biology to interpret effects of stressors

Title:	How to simplify biology to interpret effects of stressors
Category:	Miscellaneous
Date:	21. Sept. 2010, 11:00 - 12:00
Venue:	Eawag Dübendorf
	FC-C20
Speaker:	Tjalling Jager
Leader:	Roman Ashauer, Utox
Organisation:	Roman Ashauer, Utox
Download:	as calendar event

Living organisms are complex systems, and interpreting the effects of stressors (toxicants, food limitation, parasites, etc.) on these systems is a daunting task. Focusing on toxic stress, ecotoxicologists often limit themselves to rather descriptive research of the type “The effect of substance A on endpoint B of species C (influenced by environmental factor D).” However, the number of permutations of A, B, C and D is staggering; clearly, we cannot hope to test even a small fraction experimentally.

One should realise, however, that complexity is not a unique property of biology. Planets are complex entities, made up of layers, each with different chemical and physical characteristics. Nevertheless, to predict the orbits of the planets, we can reduce all this complexity to a point mass. Similarly, environmental chemists work with highly simplified models of reality to predict the fate of a chemical after its release into the environment. Can we apply a similar idealisation of reality in biology? To what extent can we simplify all living organisms in a common framework without losing important biological behaviour?

These questions have formed the backbone of the research at the department of Theoretical Biology of the VU University Amsterdam. In this lecture, I will present the outline of our general framework for an idealisation of living systems. Furthermore, I will demonstrate how this framework is used to interpret stressor effects (mainly focusing on toxicants), and how it allows for educated extrapolations to untested scenarios.