Acknowledgements

There is not enough space left to thank all the people who helped me during the time of this study. I would like to dedicate my special thanks to:

Prof. Günter Tembrock (Humboldt-University Berlin) for his supervision of my self-chosen topic, his permanent support and encouragement. With his scientific tolerance and respect of my own view he made me able to do this study.

Dr. Peter Nürnberg (Humboldt-University Berlin, now Max Delbrueck Center) has supervised my first steps into genetics. I thank Peter for his invitation to work on the Cayo project, his financial support and his encouragement throughout the study, especially during the field work.

Dr. Matt Kessler and Dr. John Berard (CPRC) for their permission to conduct this work at Cayo Santiago.

I was sharing some unique moments with friends who have also worked on Cayo and I like to thank Melissa Gerald, Cleve Hicks, Anita Stone, and Gabriel Troche for this time. Thanks to the staff of the CPRC, especially William Walker and Edgar Davila of being part of my family during these days. Ani Kazem kindly provided personal observation on group fission and male dominance. Melissa Gerald provided data on male group membership as part of the demographic data base of the CPRC.

Very special thanks go to Dr. Fred Bercovitch (CPRC, now Center for Reproduction of Endangered Species, San Diego Zoo) for his support during my days in Puerto Rico and for his unique ability to co-operate in so many aspects, especially sharing data, working on manuscripts, learning about communication, and arguing about different opinions, but coming up with a progressive conclusion. Fred is probably the one being most familiar with my work. Thanks for your help and your friendship!

For their support on the genetic analyses I am especially grateful to Heike Rösler for her support and patience in re-typing hundreds of animals. Ingrid Barth kindly provided the DNA fingerprints, Andrea Trefilov from Jörg Schmidtkes’ lab in Hanover for her co-operation, as [page 137↓]she was genotyping other groups of Cayo Santiago. Ulrike Sauermann provided data on the MHC locus.

Prof. Michael Krawczak (University of Kiel) was one of the most pleasant scientists to work with and I am really grateful for the things I learned from him not just in terms of the genetic data base and statistics, but in generally about scientific life.

Andreas Wollstein was irreplaceable in creating the behavioural data base. I also like to thank Lars Kulik for his support in entering the 1000 hours of behavioural data collected and fruitful discussions in grey days. If this thesis seems to be a bit “uncompleted” it is partly because of losing my “what-remains-to-do” file in a very bad moment. Martin Stenzel spent one night searching for this file, without success.

I am also grateful to Kornelia Dokup, Martina Rißberger and Hannes Nick for providing me with “some more papers” on kin recognition and other topics. Martina is one of my few friends who is trying to understand others even though their life is quite different.

The statistics was mainly supervised by Dr. Jürgen Streich (Institute for Zoo Biology and Wildlife Research Berlin). Jürgen is very busy supervising projects from his home institute and I am very grateful that he still finds some time to work with me after he had already supervised my Diploma project. I like to thank him one more time for his interest in my work and his patience to discuss all the statistical details with me.

Moreover, I am also grateful to Annette Simon for her supervision of my mental health during this challenging time.

Antje Engelhardt was one of closest friends during this time sharing my fascination for primates and scientific work, but also knowing about the conflicts having a child and a partner, too. I thank Antje for her friendship and support which survived even when we were separated thousands of kilometres.

I also like to thank Susan Alberts, Jeanne Altmann, Tim Clutton-Brock, Joan Silk, Kerri Smith, Sylvia Tembrock and Jo Todrank for their interest, criticism and discussion in my work. Especially, I thank Jeanne Altmann for encouraging me to believe in my data, even though the whole world believes in something else. Realising that Kerri Smith found very [page 138↓]similar things for female baboons than I found for female rhesus macaques gave me much more self-confidence in my own work.

Furthermore, I am grateful to Prof. Regine Witkowski (Institute of Medical Genetics, Charité) and the DAAD who financially supported the beginning of the field study in 1997. The years between 1998 and 2002 were financed by grants of the NaföG, the Fazit-Stiftung and the Sandmann-Stiftung. I would like to thank them for their confidence in my work. The DFG was partly supporting the assistance of Lars Kulik.

Last but not least, I like to thank my parents, sisters and friends, who have not forgotten me during this time even though they had a hard time imaging how much time and energy it requires to do scientific work. My father has influenced my personality more than anybody else making me able to go where I am now. Thanks to all of you for your patience with me and your support of my work...

...and especially you, Hagen, since you shared all the ups and downs with me. Writing both our PhD and having a little child was the most challenging and the most wonderful time I ever experienced, but I would do it again, with you! I am sure we learnt a lot as humans, lovers, parents and scientists during this time and it was worth going through all this.

My little son Jakob gave my so many smiles in days when I was depressed with this thesis and he calmed me down from hectic situations outside his own little world. And I hope the baby I am just carrying forgives me some of those stressful days we had.

Rosi Stenzel gave our little family great support in taking care of our child providing us with some good moments.

My biggest thanks, however, go to these wonderful little monkeys on Cayo Santiago. I have learnt from them the most and I really miss those wonderful peaceful days we had in the forest. Knowing a little guy named 42E whocompensates all the hits below the belt I had during my work on this thesis.

I wished human beings would watch more carefully our close relatives in order to learn things we have forgotten.