20530 Symbiosis 1

Credits: 3 advanced seminar credits in Life Sciences

Prerequisites: 36 credits in the Sciences, including General Biology I and General Biology II. Students must also fulfill all English requirements and take bibliographic instruction in the Library.

The course is based on a reader edited by Vanda Reich.

The phenomenon of symbiosis is defined as “living together of organisms which are spatially and physiologically contiguous, but belong to different biological species.” Symbiotic relations have been of vital importance in the evolution of living organisms since their appearance on earth: the emergence of the eukaryotic cell, the ability of plant-eating animals to digest plant material, the fixation of nitrogen by symbiotic microorganisms and its availability for plants, the appearance of new species such as lichens. Symbiotic relations play a central role in the development and existence of entire ecological systems such as coral reefs. The course discusses these and other topics. It also deals with how symbiotic relations form and develop and the research methods used to characterize and understand various symbiotic systems. After studying the material, students write a seminar paper.

Topics: Preface; Characteristics of symbiosis and terminology; The evolution of the eukaryotic cell; Symbiotic chloroplasts; Green hydra symbiosis; Herbivorous mammals and microbial degradation of cellulose; Cellulose degradation in insects; Hydrothermal vents: An ecosystem supported by symbiotic associations; Bioluminescence; Nitrogenfixing symbioses; Lichens; Symbiosis and evolution.


1This course is offered every semester. Students who wish to earn one extra credit (without paying tuition) can join the field trip in Symbiosis (Field Trip). For details, see the course description.