animal behaviour


research interests





- sociality, group living
- cooperation & competition
- endocrinology & social behaviour

PhD thesis (2002-2007)

'conditions and consequences of female social partner choice in wild house mice'
in the group of Prof. Barbara König,
Institute of Zoology (now: Institute of Evolutionary Biology and Environmental Studies), University of Zürich, Switzerland


Female choice of mating partners is a major topic in evolutionary biology. Several studies have shown that such partner decisions influence a female's fitness.
Choosing a mate, however, is not the only context in which females may choose partners. In group-living animals, females predominantly interact with same-sex conspecifics and cooperative relationships are frequently established. Females may be choosy and develop preferences for specific cooperation partners. Yet, female social partner choice has received little attention in the past years, and information on the mechanisms and consequences of these decisions is scarce.
This is surprising, as not only female mate choice, but also female social partner choice may be subject to social selection processes and may drive the evolution of female traits.

In my thesis, I investigated female social partner choice in a well-known in the vicinity of human habitation...the house mouse (Mus domesticus).
Those little grey animals show some
extraordinary behaviour: female house mice may cooperate by communally nursing their young, that is, they share milk between own and alien offspring.
However, in order to establish such a cooperative relationship, the choice of an appropriate social partner is likely to play a crucial role.

To examine social partner choice decisions I carried out laboratory experiments in indoor enclosures and established a population of free-ranging wild house mice in a barn. I specifically investigated the occurrence and consequences of social partner choice and the potential for social selection to take place.
Additionally, I was interested in the impact of male presence on shaping the social structure among female group members, thus influencing social partner decisions. Furthermore, I investigated possible constraints on female decisions and potential mechanisms involved in the establishment of female cooperative relationships.

Females were choosy when selecting social partners in an enclosure experiment, and such social partner choice entailed fitness benefits. Females kept with a preferred partner had a significantly higher reproductive success than females kept with a non-preferred partner. Moreover, females were also choosy in a free-ranging population. Against former suggestions, decisions for social partners were not inevitably determined by sharing nesting sites, which indicates that communal nursing behaviour is not simply a by-product of sociality. Instead, a crucial factor determining communal nursing decisions appeared to be the availability of appropriate social partners. Importantly, the presence of males significantly altered female preferences for social partners. This finding emphasizes the interplay of female-female and female-male interactions and the necessity to investigate partner choice decisions in the presence of both sexes.
Overall, I could show that in house mice not only mate choice matters. Partner choice also occurs among female group members and may just as well be subject to social selection processes.

If you are interested in more detailed information about this study, do not hesitate to contact me!

PhD thesis
Weidt, A. (2007): With Whom To Nurse? Conditions and Consequences of Female Social Partner Choice in Wild House Mice. Institute of Zoology, University of Zürich, Switzerland.


Weidt, A., Lindholm, A.K. & König, B.; 2014: Communal nursing in wild house mice is not a by-product of group-living: females choose. Naturwissenschaften 101(1):73-76. doi:10.1007/s00114-013-1130-6

Lindholm, A.K., Musolf, K., Weidt, A. & König, B.; 2013: Mate choice for genetic compatibility in the house mouse. Ecology and Evolution 3(5): 1231-1247. doi: 10.1002/ece3.534

Weidt, A., Hofmann, S. E. & König, B.; 2008: Not only mate choice matters: fitness consequences of social partner choice in female house mice. Animal Behaviour, 75: 801-808. doi: 10.1016/j.anbehav.2007.06.017

diploma thesis (2000-2001)

'ecology and social behaviour of female golden brown mouse lemurs (Microcebus ravelobensis) in northwest madagascar'
in the group of Prof. Elke Zimmermann,
Institute of Zoology, School of Veterinary Medicine, Hannover, Germany


They might be referred to as 'ghosts of the forest' or 'creatures of the night'...and they are some of the most fascinating little mammals which crossed my way so far - mouse lemurs.

For my diploma thesis, I had the great opportunity to work with golden brown mouse lemurs, a species which was only discovered in 1994.
During a 6-months field study in Ampojoroa forest in northwestern Madagascar, I investigated several aspects of the ecology and social behaviour in females.
I carried out capture-recapture studies, radio-telemetry and focal observation to learn more about the population density, the ranging patterns, the feeding behaviour, about sleeping sites and sleeping group compositions.
Together with respective data on males we were able to draw conclusions on the mating system and the social organization of this tiny, nocturnal primate.

If you are interested in some more pictures and impressions of field work on Madagascar, you might want to check out this nice travel report (unfortunately only in German) of my husband- and, by the way, also great field assistant ;-) - Jens Bredenbeck.

diploma thesis
Weidt, A. (2001): Ökologie und Sozialbiologie von Weibchen des goldbraunen Mausmakis (Micocebus ravelobensis) während der Trockenzeit in Nordwest-Madagaskar. Diplomarbeit am Institut für Zoologie und Anthropologie, Universität Göttingen, Germany.

Weidt, A.; Hagenah, N.; Randrianambinina, B.; Radespiel, U.; Zimmermann, E.; 2004: Social Organization of the Golden Brown Mouse Lemur (Microcebus ravelobensis). Am. J. Phys. Anthropol. 123:40-51. doi: 10.1002/ajpa.10296
additional scientific work experiences (1997-1999)

- with Eleni Nikitopoulos, Institute of Comparative Physiology, Department of Ethology and Socioecology, University of Utrecht, The Netherlands: Mating behaviour and male coercion in Java Monkeys (Macaca fascicularis), Ethology Station, Utrecht, The Netherlands (1998-1999)

- with Dr. Peter Kappeler, Department of Behavioral Ecology & Sociobiology/Anthropology, German Primate Center, Göttingen, Germany: Social behaviour in Redfronted Lemurs (Eulemur fulvus rufus), Kirindy research station, Madagascar (1998)

- with Dr. Arun Srivastava, Indo-US-Primate-Project, Guwahati, India (cooperation of the Indian Government and the US Fish and Wildlife Service): Primate Census, Assam, India (1997)