• Evolution of ecological novelty
    Why does scale-eating rarely evolve in Caribbean pupfishes?
  • Sympatric speciation in volcanic crater lakes
    Cast-netting for endemic cichlids in Lake Kotto, Cameroon
  • Measuring the adaptive landscape
    How does the mapping of genotype to phenotype to fitness landscape shape adaptive diversification?
  • Evolutionary diversification rates
    Pupfish 'morphogram' illustrating diversification rates in the San Salvador Island adaptive radiation relative to background rates

About the lab

Welcome to the Martin fish speciation lab! We are evolutionary biologists broadly interested in the ecology, evolution, and genomics of adaptive radiation in fishes. We use large-scale field experiments, population genetics, natural history, behavioral ecology, functional morphology, quantitative genetics, and phylogenetic methods to dissect this process at various stages.

We are primarily developing two tropical field systems for studying the origins of adaptive radiation: 1) Caribbean microendemic radiations of trophic specialist pupfishes and 2) Cameroon crater lake cichlids, famous as putative examples of sympatric speciation.

Common themes in our work include 1) the genetic, behavioral, and ecological origins of adaptive radiation in space and time, 2) estimating the major features of fitness landscapes driving this process, and 3) the evolution of novel phenotypes and ecological niches.

If you are intrigued by the speciation process, drawn to tropical field systems, and you have a particular thing about fish, I strongly encourage you to contact me! I am currently accepting graduate students through Integrative Biology at the University of California, Berkeley. I especially encourage applications from BIPOC. Please see our lab's statement of support for the Black Lives Matter movement below and our Code of Conduct here. My lab continues to discuss and educate ourselves about these issues weekly as we work to build an inclusive and diverse group.

The IB graduate program is described here (annual admissions deadline is December 3rd). For those considering a PhD, I would suggest reading the perspectives here and here. As the Curator of Ichthyology for Cal, our lab is based inside the Museum of Vertebrate Zoology with extensive shared spaces for molecular genetics work, student offices, specimen preparation, data entry, and the growing MVZ Ichthyology collection. We also maintain our fish colonies (>1000 individuals and >40 species) in four exclusive fish rooms plus roof top experimental ponds.

I am also currently seeking a postdoc with a passion for fishes and integrative biology, specifically in the fields of genomics, functional genetics, or developmental biology. I strongly encourage BIPOC to contact me if you are graduating soon or currently exploring your options for a postdoc. There are several external and internal postdoctoral fellowships available as well as options for supplemental funding to my existing grants.

Martin Lab anti-racism statement

The murders of Breonna Taylor, George Floyd, Ahmaud Arbery, Elijah McClain, Rayshard Brooks, Freddie Gray, and so many more by our police state deeply saddens and enrages us. These ongoing killings show how deeply white supremacy has rooted itself in our country. We believe that Black Lives Matter and we stand in solidarity with our Black colleagues, students, and protesters. We are committed to anti-racism and increasing diversity and inclusion in our lab group, mentorship, research, teaching, and academic spaces overall. Although we are taking incremental steps toward becoming more anti-racist and continuing to educate ourselves through weekly readings and discussion, we also recognize that white supremacy in STEM, particularly acute in our field of Evolution and Ecology and our department, is a major failing of our scientific community and is an ongoing crisis for science. Centuries of systemic racism in science and academia has left us with a largely homogeneous faculty of white men unequipped to take on our most pressing national and global crises in this century. We also recognize that our own research interests and understanding of nature has been skewed by our history of racism and the genocide of Indigenous communities and their traditional knowledge. The scientific contributions of BIPOC have been and continue to be ignored, stolen, and erased.

We strongly believe that dismantling white supremacy is the only moral choice. This promotes innovation, increases equitable access to this profession that we love, and increases our ability to communicate science and serve as role models to the local, national, and international communities we serve. We are stronger together. We consider any form of support for white supremacy to be scientific misconduct.

Lab Members

Christopher Martin

Principal Investigator

Curriculum Vitae



Recorded talks: Evolution 2014, 2016, 2017, 2019

UC Berkeley 2015, 2018 (1/2 job talk)

Emilie Richards

Graduate Student 2016-

I am broadly interested in how adaptation and speciation processes interact on a genomic level during adaptive radiations and how we harness the powerful resource of genomic data to address questions about evolutionary history. I am currently working on identifying the sources of genetic variation that fueled adaptive diversification in a radiation of trophic specialist pupfishes on a single island in the Bahamas. When I am not busy typing away at my computer, my hobbies include recreational scuba diving and watching nature documentaries with my cat. website email

Chapter 1: Adaptive introgression into a microendmic radiation (PLOS Gen 2017)

Chapter 2: Introgression in Barombi Mbo cichlids (Evo Letters 2018)

Chapter 3: Searching for sympatric speciation in the genomic era (BioEssays 2019)

Chapter 4: The spatiotemporal origins of vertebrate adaptive radiation (in review)

Michelle St. John

Graduate Student 2017-

I am interested in investigating the speciation process through the lens of fish behavior. This involves studying behavioral differences between diverging species, exploring interactions between species, and ultimately determining how these differences and interactions affect the evolution of reproductive isolation. When I am not observing fish, I enjoy cooking with my husband and hanging out with my two cats (Tulip and Alfalfa). email

Chapter 1: The aggressive behavioral origins of scale-eating (BEH 2019)

Chapter 2: Adaptive scale-eating feeding kinematics (JEB 2020)

Chapter 3: The novel behavior of oral-shelling (JFB 2020)


David Tian

Graduate Student 2019-

By combining population genetics, functional genetics, and fitness experiments, I aim to gain a comprehensive and mechanistic understanding of adaptation. Specifically, I am interested in how genetic variation underlying adaptive traits is shaped across time and space in populations and how these loci interact with each other at a molecular level to produce phenotypes. To this end, I am focused on investigating how and why a rare scale eating trophic specialist evolved its novel and extreme craniofacial morphology. email


Jacquelyn Galvez

Graduate Student 2019-

I would define myself as an evolutionary biologist with particular interests in speciation and eco-evolutionary dynamics. I have a soft spot for cichlids and aim to study the feeding kinematics, assortative mating patterns, and genomic histories of the Cameroon crater lake radiations in order to better understand sympatric speciation. When I’m not learning about fish, you can probably find me at a coffee shop with a chai latte in one hand and bullet journal in the other. email

Group Photos

Fish collecting trip to Albany Marine Park, CA (2019)


Darwin Day outreach at the NC Museum of Natural Sciences (2019)

Pup-fishing in the greatest hypersaline lake on San Salvador Island, Bahamas (2018)

Pup-collecting in an estuary, Fort Fisher, NC (2017)

March for Science (2017) (guess which 2 are lab members?!)

Alumni: Grad students and Postdocs


Joseph Heras

Postdoctoral Scholar 2020

Microbiome diversity and function in Caribbean pupfishes (in prep). Currently (August, 2020) an Assistant Professor in the Biology Department at CSU San Bernardino. website email

Jelmer Poelstra

Postdoctoral scholar 2016-2017

Demographic history of diversification in Cameroon crater lake cichlids (Mol Ecol 2018). Following a second postdoc in Anne Yoder's lab at Duke University, Jelmer is now a bioinformaticist at the Molecular and Cellular Imaging Center, Ohio State University.

Alumni: Lab managers and undergrads

Nicole Suren

Lab Manager 2019-2020

Kristi Dixon

Lab Manager 2018-2019

Currently lab manager for the Peifer lab.

Delaney O'Connell

Undergraduate 2019-2020

Logan Buie

Lab Manager 2017-2018

Currently staff at the North Carolina Museum of Natural Sciences

Stephanie Jeselson

Undergraduate 2016-2017

Clare Bocklage

Undergraduate 2015-2017


Google scholar profile

*Graduate students, †Postdoctoral scholars, •Undergraduate students

McGirr JA*, Martin CH. Ecological divergence in sympatry causes gene misregulation in hybrids. preprint

St. John ME, Martin CH. Scale-eating specialists evolved adaptive feeding kinematics within a microendemic radiation of San Salvador Island pupfishes. preprint

Martin CH, Richards EJ*. 2019. The paradox behind the pattern of rapid adaptive radiation: How can the speciation process sustain itself through an early burst? Annual Review of Ecology, Evolution, and Systematics 50:569-593. pdf

Martin CH, McGirr JA*, Richards EJ*, St. John ME*. 2019. How to investigate the origins of novelty: insights gained from genetic, behavioral, and fitness perspectives. Integrative Organismal Biology pdf

McGirr JA*, Martin CH. 2019. Hybrid gene misregulation in multiple developing tissues within a recent adaptive radiation of Cyprinodon pupfishes. PLOS One 14:e0218899. pdf

Richards EJ*, Servedio MR, Martin CH. 2019. Searching for sympatric speciation in the genomic era. BioEssays 41:1900047. pdf

St. John ME, McGirr JA, Martin CH. 2019. The behavioral origins of novelty: did increased aggression lead to scale-eating in pupfishes? Behavioral Ecology 30:557-569. pdf

Martin CH, Richards EJ*. 2019. The paradox behind the pattern of rapid adaptive radiation: how can the speciation process sustain itself through an early burst? Annual Review of Ecology, Evolution, and Systematics pdf

Davis AL•, Babb MH•, Lowe MC•, Yeh AT•, Lee BT•, Martin CH. 2019. Testing Darwin’s hypothesis about the wonderful Venus flytrap: marginal spikes form a “horrid prison” for moderate-sized insect prey. American Naturalist 93:309-317. pdf Media: Atlas Obscura Phys.org ScienceDaily

McGirr JA*, Martin CH. 2018. Parallel evolution of gene expression between trophic specialists despite divergent genotypes and morphologies. Evolution Letters 2:62-75. pdf

Richards EJ*, Poelstra JW†, Martin CH. 2018. Don’t throw out the sympatric species with the crater lake water: fine-scale investigation of introgression provides weak support for functional role of secondary gene flow. Evolution Letters 2:524-540. pdf

Poelstra JW†, Richards EJ*, Martin CH. 2018. Speciation in sympatry with ongoing secondary gene flow and a potential olfactory trigger in a radiation of Cameroon cichlids. Molecular Ecology 27:4270–4288. pdf

Martin CH, Turner BJ. 2018. Long-distance dispersal over land by fishes: extremely rare ecological events become probable over millennial timescales. Proceedings of the Royal Society B 285: 20172436. pdf

Zeng Y•, Martin CH. 2017. Oxford Nanopore sequencing in a research-based undergraduate course. preprint

Keren T, Kiflawi M, Martin CH, China V, Mann O, Holzman R. 2017. A complex performance landscape for suction-feeding reveals constraints and adaptations in a population of reef damselfish. preprint

Hernandez LP, Adriaens D, Martin CH, Wainwright PC, Masschaele B, Derick M. 2017. Building trophic specializations that result in substantial niche partitioning within a young adaptive radiation. Journal of Anatomy. 232:173-185. pdf

Richards EJ*, Martin CH. 2017. Adaptive introgression from distant Caribbean islands contributed to the diversification of a microendemic radiation of trophic specialist pupfishes. PLOS Genetics 13:e1006919. pdf Media: ScienceDaily

Stager JC, Alton K, Martin CH, King DT, Livingstone DT. 2017. On the age and origin of Lake Ejagham and its endemic fishes. 2017. Quaternary Research. 89:21-32. pdf

Martin CH, Höhna S. 2017. New evidence for the recent divergence of Devil's Hole pupfish and the plausibility of elevated mutation rates in endangered taxa. Molecular Ecology. 27:831-83. pdf

Martin CH, Höhna S, Crawford JE, Turner BJ, Richards EJ*, Simons LH. 2017. The complex effects of demographic history on the estimation of substitution rate: concatenated gene analysis results in no more than twofold overestimation. Proceedings of the Royal Society B 284:20170537. pdf

Martin CH, Erickson PA, Miller CT. 2017. The genetic architecture of novel trophic specialists: higher effect sizes are associated with exceptional oral jaw diversification in a pupfish adaptive radiation. Molecular Ecology 26:624-638. pdf supplement

McGirr JA*, Martin CH. 2016. Novel candidate genes underlying extreme trophic specialization in Caribbean pupfishes. Molecular Biology and Evolution 34:873-888. pdf supplement Media: Phys.org ScienceDaily

Martin CH. 2016. The cryptic origins of evolutionary novelty: 1,000-fold-faster trophic diversification rates without increased ecological opportunity or hybrid swarm. Evolution 70:2504-2519. pdf supplement

Higham TE, Rogers SM, Langerhans RB, Jamniczky HA, Lauder GV, Stewart WJ, Martin CH, Reznick DN. 2016. Speciation through the lens of biomechanics: locomotion, prey capture, and reproductive isolation. Proceedings of the Royal Society B 283:1294-1304. pdf

Martin CH. 2016. Context-dependence in complex adaptive landscapes: frequency and trait-dependent selection surfaces within an adaptive radiation of Caribbean pupfishes. Evolution 69:1406-1422. pdf supplement

Martin CH, Crawford JE, Turner BJ, Simons LH. 2016. Diabolical survival in Death Valley: recent pupfish colonization, gene flow, and genetic assimilation in the smallest species range on earth. Proceedings of the Royal Society B 283:23-34. pdf supplement Media: Nature Science Science Magazine BBC Discovery News New Scientist Quirks and Quarks CBC radio interview

Martin CH, Cutler JS, Friel JP, Dening Touokong C, Coop G, Wainwright PC. 2015. Complex histories of repeated gene flow in Cameroon crater lake cichlids cast doubt on one of the clearest examples of sympatric speciation. Evolution 69:1406-1422. pdf Jerry Coyne's jubilant blog posts: 1 2

Musilová Z, Indermaur A, Nyom ARB, Tropek R, Martin CH, Schliewen UK. 2014. Persistence of Stomatepia mongo, an endemic cichlid fish of the Barombi Mbo Crater Lake, Southwestern Cameroon, with notes on its life history and behavior. Copeia 2014:556-560. pdf

Martin CH, Feinstein LC. 2014. Novel trophic niches drive variable progress toward ecological speciation within an adaptive radiation of pupfishes. Molecular Ecology. 23: 1846-1862. pdf

Martin CH, Wainwright PC. 2013. A remarkable species flock of Cyprinodon pupfishes endemic to San Salvador Island, Bahamas. Bulletin of the Peabody Museum of Natural History. 54:231-240. pdf  Media: UC Davis blog, Seriously Fish.

Schmitz L, Motani R, Oufiero CE,Martin CH, McGee MD, Wainwright PC. 2013. Potential enhanced ability of giant squid to detect sperm whales is an exaptation tied to their large body size. BMC Evolutionary Biology 13:226. pdf

Friedman M, Keck BP, Dornburg A, Eytan RI, Martin CH, Hulsey CD, Wainwright PC, Near TJ. 2013. Molecular and fossil evidence place the origin of cichlid fishes long after Gondwanan rifting. Proceedings of the Royal Society B 280:1770. pdf

Martin CH, Wainwright PC. 2013. On the measurement of ecological novelty: scale-eating pupfish are separated by 168 million years from other scale-eating fishes. PLOS One 8:e71164. pdf

Martin CH. 2013. Strong assortative mating by diet, color, size, and morphology but limited progress toward sympatric speciation in a classic example: Cameroon crater lake cichlids. Evolution 67:2114-2123. pdf

Martin CH, Wainwright PC. 2013. Multiple fitness peaks on the adaptive landscape drive adaptive radiation in the wild. Science 339:208-211. pdf supplement press release Media: Carl Zimmer's blog.  Seriously Fish. Der Spiegel. Nothing in Biology Makes Sense.WhyFiles. Davis Enterprise.

Schmitz L, Motani R, Oufiero CE, Martin CH, McGee MD, Gamarra AR, Lee JJ, Wainwright PC. 2013. Allometry indicates giant eyes of giant squid are not exceptional. BMC Evolutionary Biology 13:45. pdf

Martin CH. 2012. Weak disruptive selection and incomplete phenotypic divergence in two classic examples of sympatric speciation: Cameroon crater lake cichlids. American Naturalist 180:E90-109. pdf supplement press release 

Martin CH, Wainwright PC. 2011. Trophic novelty is linked to exceptional rates of morphological diversification in two adaptive radiations of Cyprinodon pupfishes. Evolution 65:2197-2212. pdf.supplement. press release. F1000. Media: MSNBC. UC Davis Aggie. Practical Fishkeeping. KillieNutz. LiveScience. anti-evolution press: Lutheran. spoof attack.

Martin CH. 2010. Unexploited females and unreliable signals of male quality in a Malawi cichlid bower polymorphism. Behavioral Ecology 21:1195-1202. pdf

Martin CH, Genner MJ. 2009. A role for male bower size as an intrasexual signal in a Lake Malawi cichlid fish. Behaviour 146:963-978. pdf

Martin CH, Genner MJ. 2009. High niche overlap between two successfully coexisting pairs of Lake Malawi cichlids.  Canadian Journal of Fisheries and Aquatic Sciences. 66:579-588. pdf supplement

Martin CH, Johnsen S. 2007. A field test of the Hamilton-Zuk hypothesis in the guppy Poecilia reticulata. Behavioral Ecology and Sociobiology 61:1897-1909. pdf

Yang AS, Martin CH, Nijhout HF. 2004. Geographic variation of caste structure among ant populations. Current Biology 14: 514-519. pdf.


Cameroon 2016

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Bahamas 2015

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Bahamas 2014

Bahamas 2013

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Death Valley 2012

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Bahamas 2011

Dominican Republic 2011

Limia perugiae collected from Lago Enriquillo.

Cameroon 2010

Sarotherodon knauerae, previously S.

Mexico 2009

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Bahamas 2008

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Malawi 2006-2007

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Madagascar 2005

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Peru 2004

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Trinidad 2004

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Costa Rica 2003

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