Malin Ah-King

621 Charles E. Young Dr. S

Department of Ecology & Evolutionary Biology

University of California, Los Angeles

Los Angeles, CA 90095

Phone: (424) 249 2746


I'm a post-doctoral researcher at department of Ecology and Evolutionary Biology, UCLA. I'm currently collaborating with Patricia Gowaty on two projects, a phylogenetic study of the evolution of sex chromosomes and a review of flexible mate choice. I have a PhD from the department of Zoology Stockholm University, Sweden and have also been a post-doc at the Centre for Gender Research at Uppsala University, Sweden.


Projects in collaboration with Patricia Gowaty UCLA:

Why evolve sex chromosomes? Testing a hypothesis of parental conflict over offspring sex ratio

The diversity in sex determination mechanisms in animals is enormous, shifting frequently between genetic and environmental sex determination and female and male heterogametic systems. Several explanations have been proposed to account for the evolution of sex determining mechanisms, however, most of these explanations are proximate. Here we suggest a novel ultimate hypothesis - that parental conflict over sex ratio is an important selective force favouring the evolution of heterogamety. The heterogametic sex can be seen as a momentary winner of the conflict. Once heterogamety has evolved, the idea predicts that the homogametic sex will evolve counter strategies to win back or increase its control over offspring sex ratio, such as parental care or internal fertilization.

One important assumption of this hypothesis is that there are ecological situations that promote the conflict between the parents. If parents have no interaction with their offspring after spawning, e.g. in pelagic spawners, there would be no selection for sex chromosomes.

We will conduct a phylogenetic study of evolution of heterogametic sex determination in fishes in relation to habitat, parental care and internal versus external fertilization. Fish are ideal for testing this hypothesis since both parental care and sex chromosomes has evolved numerous times in this taxon.

This project is important because it addresses the adaptive significance of sex chromosomes from the perspective of one of the most well respected and influential ideas about natural selection, namely Fisher's theory of the evolution of progeny sex ratios.

Flexible mate choice

The literature of mate choice is now vast, in this project we review recent empirical evidence of flexible mate choice in diverse taxa showing that individuals commonly change their behavior depending on the social or ecological situations they are experiencing. Likewise, recent theory says that accepting or rejecting potential mates (being "choosy" or "indiscriminate") changes as a function of, for example, encounters with potential mates, the focal individual's survival probability, and the size of the pool of potential mates. Observations demonstrate that adaptive flexibility in reproductive decision-making is apparently ubiquitous occurring in both males and females of most species. We therefore emphasize currently unanswered empirical questions about the distribution of flexibility in reproductive decisions of individuals.

Other collaboration projects

Variability in sexes and sexualities in nature, an evolutionary perspective, a collaboration with Sören Nylin Zoologiska institutionen, Stockholms Universitet.

In order to depart from thinking about biological sex as something static, we would like to develop the concept that in an evolutionary perspective sex can be viewed as a reaction norm. Sex determination itself is plastic. In humans, genes on the sex chromosomes decide the inner environment that makes secondary sexual characteristics develop, but they develop from genes that actually exist in both sexes. In many other species, sex determination is even more plastic with for instance ambient temperature determining to which sex an individual will develop, and changes in sex later in life also occur in a range of species.
Viewing sex as the result of an interplay between genes and the environment - a reaction norm - could facilitate a gender-neutral understanding of sex and sex differences in behaviour. From this point of view, sexual differences are not expected to generally fall into neat, discrete, pre-determined classes.

Sex roles in animals, collaboration with Ingrid Ahnesjö, Evolutionary Biology Centre, Uppsala University.

We review definitions of sex roles in animals and how they have been used for different animal groups. Is there a problem with putting this range of behaviours into the dichotomy of species with sex-role reversal and those with conventional sex roles? What about the antropomorphism? Could we depart from using the term sex roles in biology?

Call for papers (deadline May 1, 2010): 

Challenging Popular Myths of Sex, Gender and Biology

This call for papers is for a transdisciplinary anthology about gender and biology written by international researchers, aimed at a public audience. Empirical research in biology, psychology, and other life sciences sometimes undergirds popular notions of female and male sexual difference, while much of current biology actually opens a space for variable and non-static views of sex and gender; instead of emphasizing dichotomous difference, the natural sciences may look into sameness and the continuum of morphologies, behaviors and processes in between. Our aim is to make these insights public knowledge.

For more information please see the full Call for Papers here.

Upcoming seminars

Symposium on the Ecology of Sex Roles at the ISBE conference in Perth, October 2, 2010.

Invited speaker at a conference on Natural Sciences and Gender Studies, University of Bergen, Norway, December 2-3, 2010.

Invited speaker at a lecture series on Biology and Gender, Freie Universität Berlin, Germany, December 14, 2010.


Ah-King, M. “Flexible mate choice” in Encyclopedia of Animal Behavior, Elsevier. Edited by Janice Moore and Michael D. Breed. Forthcoming 2010.

Ah-King, M. “Gender and queer perspectives on Evolutionary Biology”. In: Never mind the gap! Gendering Science in Transgressive Encounters, Blomqvist, M. & Lindsmyr E. (eds) Centre for Gender Research, Uppsala University. Forthcoming 2010.

Ah-King, M. 2010. Homosexuality in animals. Sappho for Equality's magazine Swakanthey, a LGBT-organisation in Kolkata, India.

Ah-King, M. Toy story – en vetenskaplig kritik av forskning om apors leksakspreferenser. 2009. Tidskrift för genusvetenskap, 2-3. (Toy story – a scientific critique of primate toy preference research. Swedish Journal of Gender studies.)

Kvarnemo, C., Lindenfors, P., Ah-King, M. and I. Ahnesjö. 2009. Workshop review of: Gender perspectives on the development of sexual selection theory, Uppsala, October 2008 ISBE Newsletter Volume 21 Issue 1.

Ah-King. M. 2009. Queer nature, towards a non-normative perspective on biological diversity. In: Body claims, Bromseth J., Folkmarson Käll L. & Mattsson K. 

Ah-King, M. 2007. Sexual selection revisited– towards a gender-neutral theory and practise: A Response to Vandermassen’s ‘Sexual Selection, A Tale of Male Bias and Feminist Denial'. European Journal of Women’s Studies 14:4, 341-348. pdf

Ah-King, M., Elofsson, H., Kvarnemo, C., Rosenqvist, G. and Berglund, A. 2006. Why no sperm competition in a pipefish with externally brooding males? Insights from sperm activation and morphology. Journal of Fish Biology 68: 1-5. pdf

Ah-King, M., Kvarnemo C. & Tullberg, B. S. 2005. The influence of territoriality and mating system for the evolution of male care, a phylogenetic study on fish.
Journal of Evolutionary Biology 18, 371-382. pdf

Ah-King, M. 2003. Phylogenetic analyses of parental care evolution. ISBN-91-7265-776-6. Dept. of Zoology, Stockholm University. Doctoral thesis.

Kvarnemo, C., Simmons, L.W., Ah-King, M. & Elofsson H. 2003. The myth of the sperm cloud - or why is testes size not affected by spawning mode in seahorses and pipefishes. Abstract of the Fisheries Society of the British Isles Symposium, Norwich, UK. Journal of Fish Biology, Suppl. A, 63: 235.

Tullberg, B., Ah-King, M. & Temrin, H. 2002. Phylogenetic reconstruction of the parental-care system in the ancestors of birds. Phil Trans R Soc Lond B 357, 251-257. pdf

Ah-King, M. & Tullberg, B. 2000. Phylogenetic analysis of twinning in Callitrichinae.
American Journal of Primatology 51 (2):135-146. pdf