2005
Senior Scientist, Cognitive Ethology Lab, German Primate Center

2004
Senior Scientist, Section of Addiction Research, Department of Psychiatry,
University Hospital Tübingen

2001
Senior Scientist, Department of Neurobiology, German Primate Center

1996
Visiting Scientist, National Institute of Child Health and Human Development, NIH

1994
Scientific Assistant at the FU Berlin, Institute of Behavioral Biology.

1991
Ph. D. in Zoology, FU Berlin: Vocal communication in Barbary macaques

1988
Knowledge Engineering: Development and support of AI software, GNB
(Siemens & Nixdorf) and Expertise.

1986
Computer Science, TU Berlin.

1985
Diploma in Biology, FU Berlin: Acoustic communication in Nightingales

 

2021

Gultekin Y, Hildebrand D, Hammerschmidt K, & Hage S (2021). High plasticity in marmoset monkey vocal development from infancy to adulthood
Science Advances 7(27): eabf2938  - DOI -

Stephan G, Leidhold J, Hammerschmidt K (2021). Pet dogs home alone: A video-based study. Applied Animal Behaviour Science 244: 105463  - DOI -

Walb R, von Fersen L, Meijer T, Hammerschmidt K (2021). Individual differences in the vocal communication of Malayan tapirs (Tapirus indicus) considering familiarity and relatedness
Animals 11(4): 1026  - DOI -

2020

Fischer J, Wegdell F, Trede F, Dal Pesco F, & Hammerschmidt K (2020). Vocal convergence in a multi-level primate society: insights into the evolution of vocal learning. Proceedings of the Royal Society B: Biological Sciences 287: 20202531  - DOI -

Ivanenko A, Watkins P, van Gerven MAJ, Hammerschmidt K, Englitz B (2020). Classifying sex and strain from mouse ultrasonic vocalizations using deep learning. PLoS Computational Biology 16(6): e1007918  - open access -

Lausen A, Hammerschmidt K (2020). Emotion recognition and confidence ratings predicted by vocal stimulus type and acoustic parameters. Humanities & Social Sciences Communications  - DOI -

2019

Fischer J, Hammerschmidt K (2019). Towards a new taxonomy of primate vocal production learning
Philosophical Transactions of the Royal Society B: Biological Sciences 375(1789): 20190045
-abstract -

Fischer J, Higham JP, Alberts SC, Barrett L, Beehner JC, Bergman TJ, Carter A, Collins A, Dunbar R, Elton S, Fagot J, Ferreira da Silva M, Hammerschmidt K, Henzi P, Jolly CJ, Knauf S, Kopp G, Rogers J, Roos C, Ross C, Seyfarth RM, Silk J, Snyder-Mackler N, Städele V, Swedell L, Wilson ML, Zinner D (2019). The Natural History of Model Organisms: Insights into the evolution of social systems and species from baboon studies. eLife 8: e50989  - open access -

Hammerschmidt K, Fischer J (2019). Baboon vocal repertoires and the evolution of primate vocal diversity. Journal of Human Evolution 126: 1-13  - open access -

Hülsmann S, Oke Y, Mesuret G, Latal AT, Fortuna MG, Niebert M, Hirrlinger J, Fischer J, Hammerschmidt K (2019). The postnatal development of ultrasonic vocalization-associated breathing is altered in glycine transporter 2-deficient mice. Journal of Physiology 597(1): 173-191   - abstract -

Ordóñez-Gómez JD, Santillan-Doherty AM, Hammerschmidt K (2019). Acoustic variation of spider monkey (Ateles geoffroyi) contact calls is related to caller isolation. PLOS ONE 14(4): e0213914  - open access -

Wegdell F, Hammerschmidt K, Fischer J (2019). Conserved alarm calls but rapid auditory learning in monkey responses to novel flying objects. Nature Ecology & Evolution 3: 1039-1042   - abstract -

2018

Bernaldo de Quirós E, Wheeler BC, Hammerschmidt K, Heistermann M, Tiddi B (2018). Do sexual calls in female black capuchin monkeys (Sapajus nigritus) vary with fertility? An acoustic analysis. American Journal of Primatology 80(9): e22920  - abstract -

Ordóñez-Gómez JD, Santillán-Doherty AM, Fischer J, Hammerschmidt K (2018). Acoustic variation of spider monkeys’ contact calls (whinnies) is related to distance between vocalizing individuals and immediate caller behavior. American Journal of Primatology 80(4): e22747  - abstract -

Winkler D, Daher F, Wüstefeld L, Hammerschmidt K, Poggi G,Seelbach A, Krueger-Burg D, Vafadari B, Ronnenberg A, Liu Y, Kaczmarek L, Schlüter OM, Ehrenreich H, Dere E (2018). Hypersocial behavior and biological redundancy in mice with reduced expression of PSD95 or PSD93. Behavioural Brain Research 352: 35-45   - abstract -

2017

Almeling L, Sennhenn-Reulen H, Hammerschmidt K, Freund AM, Fischer J (2017)
Social interactions and activity patterns of old Barbary macaques: further insights into the foundations of social selectivity
American Journal of Primatology 79 (11): e22711  - abstract -

Fischer J, Kopp GH, Dal Pesco F, Goffe A, Hammerschmidt K, Kalbitzer U, Klapproth M, Maciej P, Ndao I, Patzelt A, Zinner D (2017)
Charting the neglected West: the social system of Guinea baboons
Yearbook of Physical Anthropology, Volume 162, Issue Supplement S63, pp 15-31  - open access -

Fischer J, Farnworth MS, Sennhenn-Reulen H, Hammerschmidt K (2017). Quantifying social complexity. Animal Behaviour 130: 57-66  - abstract - 

Fischer J, Wadewitz P, Hammerschmidt K (2017)
Structural variability and communicative complexity in acoustic communication
Animal Behaviour 134: 229-237  - open access -

Mitjans M, Begemann M, Ju A, Dere E, Wüstefeld L, Hofer S, Hassouna I, Balkenhol J, Oliveira B, van der Auwera S, Tammer R, Hammerschmidt K, Völzke H, Homuth G, Cecconi F, Chowdhury K, Grabe H, Frahm J, Boretius S, Dandekar T, Ehrenreich H (2017)
Sexual dimorphism of AMBRA1-related autistic features in human and mouse
Translational Psychiatry 7: e1247  - open access -

Vester H, Hallerber S, Timme M, Hammerschmidt K (2017)
Vorcal repertoire of long-finned pilot whales (Globicephala melas) in northern Norway
The Journal of the Acoustical Society of America 141 (6): 4289-4299   - open access -

2016

Almeling L, Hammerschmidt K, Sennhenn-Reulen H, Freund A M, Fischer J (2016)
Motivational shifts in aging monkeys and the origins of social selectivity
Current Biology 26: 1744-1749  - abstract -

Erb WM, Ziegler T, Lestari NS, Hammerschmidt K (2016)
Are simakobu (Simias concolor) loud calls energetically costly signals?
American Journal of Physical Anthropology 161(1): 44-52  - open access -

Pfefferle D, Hammerschmidt K, Mundry R, Ruiz-Lambides AV, Fischer J, Widdig A (2016)
Does the Structure of Female Rhesus Macaque Coo Calls Reflect Relatedness and/or Familiarity?
PLoS One 11(8): e0161133   - open access

Vester H, Hammerschmidt K, Timme M, Hallerberg S (2016 )
Quantifying group specificity of animal vocalizations without specific sender information
Physical Review E 93(2): 022138  - abstract

2015

Hammerschmidt K, Schreiweis C, Minge C, Pääbo S, Fischer J, Enard W (2015)
A humanized version of Foxp2 does not affect ultrasonic vocalization in adult mice
Genes, Brain and Behavior 14(8): 583-590   - open access -

Hammerschmidt K, Whelan G, Eichele G, Fischer J (2015)
Mice lacking the cerebral cortex develop normal song: Insights into the foundations of vocal learning
Scientific Reports 5: 8808  - open access -

Price T, Wadewitz P, Cheney D, Seyfarth R, Hammerschmidt K, Fischer J (2015)
Vervets revisited: A quantitative analysis of alarm call structure and context specificity
Scientific Reports 5: 13220  - open access -

Wadewitz P, Hammerschmidt K, Battaglia D, Witt A, Wolf F, Fischer J (2015)
Characterizing vocal repertoires - hard vs. soft classification approaches
PLoS ONE 10(4): e0125785  - open access -

2014

Dere E, Dahm L, Lu D, Hammerschmidt K, Ju A, Tantra M, Kästner A, Chowdhury K,
Ehrenreich H (2014)
Heterozygous Ambra1 deficiency in mice: A genetic trait with autism-like behavior
restricted to the female gender
Frontiers in Behavioral Neuroscience 8(181): 1-19  - pdf available via open access -

Hedwig D, Hammerschmidt K, Mundry R, Robbins MM, Boesch C (2014)
Acoustic structure and variation in mountain and western gorilla close calls: a syntactic approach
Behaviour 151(8): 1091-1120 - abstract -

Ju A, Hammerschmidt K, Tantra M, Krueger D, Brose N, Ehrenreich H (2014)
Juvenile manifestation of ultrasound communication deficits in the neuroligin-4 null mutant mouse model of autism
Behavioural Brain Research 270:159-164  - abstract -

Price T, Ndiaye O, Hammerschmidt K, Fischer J (2014)
Limited geographic variation in the acoustic structure of and responses to adult male alarm barks of African green monkeys
Behavioral Ecology and Sociobiology 68(5): 815-825  - pdf available via open access -

Salmi R, Hammerschmidt K, Doran-Sheehy DM (2014)
Individual Distinctiveness in Call Types of Wild Western Female Gorillas
PLoS ONE 9(7): e101940  - pdf available via open access -

Tantra M, Hammer C, Kästner A, Dahm L, Begemann M, Bodda C, Hammerschmidt K, Giegling I, Stepniak B, Venzor AC, Konte B, Erbaba B, Hartmann A, Tarami A, Schulz-Schaeffer W, Rujescu D, Mannan AU, Ehrenreich H (2014)
Mild expression differences of MECP2 influencing aggressive social behavior
EMBO Molecular Medicine 6(5): 662-684  - pdf available via open access -

2013

Barelli C, Mundry R, Heistermann M, Hammerschmidt K (2013)
Cues to androgen and quality in male gibbon songs
PLoS ONE 8(12): e82748  - pdf available via open access -

El-Kordi A, Kästner A, Grube S, Klugmann M, Begemann M, Sperling S, Hammerschmidt K, Hammer C, Stepniak B, Patzig J, de Monasterio-Schrader P, Strenzke N, Flügge G, Werner HB, Pawlak R, Nave K-A, Ehrenreich H (2013)
A single gene defect causing claustrophobia
Translational Psychiatry 3(4), e254  - pdf available via open access -

El-Kordi A, Winkler D, Hammerschmidt K, Kästner A, Krueger D, Ronnenberg A, Ritter C, Jatho J, Radyushkin K, Bourgeron T, Fischer J, Brose N, Ehrenreich H (2013)
Development of an autism severity score for mice using Nlgn4 null mutants as a construct-valid model of heritable monogenic autism
Behavioural Brain Research 251: 41-49   - abstract -

Erb WM, Hodges JK, Hammerschmidt K (2013)
Individual, contextual and age-related acoustic variation in simakobu (Simias concolor)
loud calls
PLoS ONE 8(12): e83131  - pdf available via open access -

Fischer J, Noser R, Hammerschmidt K (2013)
Bioacoustic field research: a primer to acoustic analyses and playback experiments with primates
American Journal of Primatology 75(7): 643-663  - pdf available via open access -

Illmann G, Hammerschmidt K, Špinka M, Tallet C (2013)
Calling by Domestic Piglets during Simulated Crushing and Isolation: A Signal of Need?
PLoS ONE 8(12): e83529  - pdf available via open access -

Maciej P, Ndao I, Hammerschmidt K, Fischer J (2013)
Vocal communication in a complex multi-level society: constrained acoustic structure and flexible call usage in Guinea baboons
Frontiers in Zoology 10:58  - pdf available via open access -

Maciej P, Patzelt A, Ndao I, Hammerschmidt K, Fischer J (2013)
Social monitoring in a multilevel society: a playback study with male Guinea baboons 
Behavioral Ecology and Sociobiology 67: 61-68   - pdf available via open access -

Salmi R, Hammerschmidt K, Doran-Sheehy DM (2013)
Western Gorilla Vocal Repertoire and Contextual Use of Vocalizations
Ethology 119(10): 831-847  - pdf available via open access -

Tallet C, Linhart P, Policht R, Hammerschmidt K, Šimeček P, Kratinova P, Špinka M (2013)
Encoding of Situations in the Vocal Repertoire of Piglets (Sus scrofa): A Comparison of Discrete and Graded Classifications
PLoS ONE 8(8): e71841  - pdf available via open access -

Vester H, Hammerschmidt K (2013)
First record of killer whales (Orcinus orca) feeding on Atlantic salmon (Salmo salar) in northern Norway suggest a multi-prey feeding type
Marine Biodiversity Records 6: 1-5 - abstract -

Wheeler BC, Hammerschmidt K (2013)
Proximate factors underpinning receiver responses to deceptive false alarm calls in wild tufted capuchin monkeys: Is it counter-deception?
American Journal of Primatology 75(7): 715-725  - pdf available via open access -

2012

Hammerschmidt K, Radyushkin K, Ehrenreich H, Fischer J (2012)
The Structure and Usage of Female and Male Mouse Ultrasonic Vocalizations Reveal only Minor Differences
PLoS ONE 7(7): e41133   - pdf available via open access -

Hammerschmidt K, Reisinger E, Westekämper K, Ehrenreich L, Strenzke N, Fischer J (2012)
Mice do not require auditory input for the normal development of their ultrasonic vocalizations
BMC Neuroscience 2012, 13:40   - pdf available via open access -

Meyer D, Hodges JK, Rinaldi D, Wijaya A, Roos C, Hammerschmidt K (2012)
Acoustic structure of male loud-calls support molecular phylogeny of Sumatran and Javanese leaf monkeys (genus Presbytis)
BMC Evolutionary Biology 2012, 12:16   - pdf available via open access -

2011

Fischer J, Hammerschmidt K (2011)
Ultrasonic vocalizations in mouse models for speech and socio-cognitive disorders: insights into the evolution of vocal communication
Genes, Brain and Behavior 10(1): 17-27   - pdf available via open access -

Jürgens R, Hammerschmidt K, Fischer J (2011)
Authentic and play-acted vocal emotion expressions reveal acoustic differences
Frontiers in Emotion Science 2: 180   - pdf available via open access -

Maciej P, Fischer J, Hammerschmidt K (2011)
Transmission Characteristics of Primate Vocalizations: Implications for Acoustic Analyses
Plos ONE 6: e23015   - pdf available via open access -

Schell A, Rieck K, Schell K, Hammerschmidt K, Fischer J (2011)
Adult but not juvenile Barbary macaques spontaneously recognize group members from pictures
Animal Cognition 14(4): 503-509   - pdf available via open access -

Thinh VN, Hallam C, Roos C, Hammerschmidt K (2011)
Concordance between vocal and genetic diversity in crested gibbons
BMC Evolutionary Biology 11:36   - pdf available via open access -

2010

Neumann C, Assahad G, Hammerschmidt K, Farajallah DP, Engelhard A (2010)
Loud calls in male Macaca nigra - a signal of dominance in a tolerant primate species.
Animal Behaviour 79: 187-193   - abstract -

Seyfarth RM, Cheney DL, Bergman T, Fischer J, Zuberbühler K, Hammerschmidt K (2010)
The central importance of information in studies of animal communication.
Animal Behaviour 80: 3-8   - abstract -

Thinh VN, Nadler T, Roos C, Hammerschmidt K (2010) 
Taxon-Specific vocal characteristics of crested gibbons (Nomascus spp.).
In: T Nadler, BM Rawson, VN Thinh (eds) Conservation of primates in Indochina. 
Frankfurt Zoological Society, Hanoi, pp 121-132

2009

Enard W, Gehre S, Hammerschmidt K, Holter SM, Blass T, Somel M, Bruckner MK, Schreiweis C, Winter C, Sohr R, Becker L, Wiebe V, Nickel B, Giger T, Muller U, Groszer M, Adler T, Aguilar A, Bolle I, Calzada-Wack J, Dalke C, Ehrhardt N, Favor J, Fuchs H, Gailus-Durner V, Hans W, Holzlwimmer G, Javaheri A, Kalaydjiev S, Kallnik M, Kling E, Kunder S, Mossbrugger I, Naton B, Racz I, Rathkolb B, Rozman J, Schrewe A, Busch DH, Graw J, Ivandic B, Klingenspor M, Klopstock T, Ollert M, Quintanilla-Martinez L, Schulz H, Wolf E, Wurst W, Zimmer A, Fisher SE, Morgenstern R, Arendt T, de Angelis MH, Fischer J, Schwarz J, Paabo S (2009)
A Humanized Version of Foxp2 Affects Cortico-Basal Ganglia Circuits in Mice.
Cell 137: 961-971

Ey E, Rahn C, Hammerschmidt K, Fischer J (2009)
Wild female olive baboons adapt their grunt vocalisations to environmental conditions.
Ethology 115: 493-503

Hammerschmidt K, Radyushkin K, Ehrenreich H, Fischer J (2009)
Female mice respond to male ultrasonic 'songs' with approach behaviour.
Biology Letters 5: 589-592

Radyushkin K, Hammerschmidt K, Boretius S, Varoqueaux F, El-Kordi A, Ronnenberg A, Winter D, Frahm J, Fischer J, Brose N, Ehrenreich H (2009)
Neuroligin-3-deficient mice: model of a monogenic heritable form of autism with an olfactory deficit.
Genes Brain and Behavior 8: 416-425

2008

Hammerschmidt K, Fischer J (2008) . Constraints in primate vocal production. In: K Oller, U Griebel (eds) Evolution of Communicative Flexibility: Complexity, Creativity, and Adapability in Human and Animal Communication.
The MIT Press, Cambridge. MA, pp 93-119

Jamain S, Radyushkin K, Hammerschmidt K, Granon S, Boretius S, Varoqueaux F, Ramanantsoa N, Gallego J, Ronnenberg A, Winter D, Frahm J, Fischer J, Bourgeron T, Ehrenreich H, Brose N (2008). Reduced social interaction and ultrasonic communication in a mouse model of monogenic heritable autism. Proceedings of the National Academy of Sciences of the United States of America 105: 1710-1715

Scheiner E, Hammerschmidt K (2008). The role of auditory feedback in nonverbal vocal behavior of normally hearing and hearing-impaired infants
In: K Izdebski (ed) Emotions in the human voice. 
Plural Publishing, San Diego

Schmitt V, Melchisedech S, Hammerschmidt K, Fischer J (2008). Hand preferences in Barbary macaques (Macaca sylvanus). Laterality 13: 143-157

Schneider C, Hodges JK, Fischer J, Hammerschmidt K (2008). Acoustic niches of siberut primates.
International Journal of Primatology 29: 601-613