Principal Investigator:

Jim inspecting a strangler fig on the trail to Gunung Torompupu on Sulawesi Island. Of course, Cynthia Wang-Claypool has captured the real Jim, which can only be viewed by clicking on this image – The Immaculate Draco – one plug, one Draco in the hand, plug recovered!

Jim McGuire: Jim’s primary research interests are in phylogenetics, population genetics, biogeography, and comparative biology of reptiles, amphibians, and hummingbirds. He is particularly interested in how complex faunas, such as those of Sulawesi and Indonesia’s Lesser Sunda Islands, have been assembled over time, as well as the processes underpinning diversification, and how species both form and sometimes merge again following secondary contact. Jim has a long-standing interest in hummingbird adaptation to high-elevation environments. A more recent interest is the elevational diversification of amphibians and reptiles on the mountains of Sulawesi.



Ammon in the field in the Namib Desert.

Ammon Corl: Ammon’s research has dealt with four broad areas aimed at better understanding evolutionary diversification, including 1) the factors leading to the evolution of new species, 2) the effects of sexual selection on phenotypic and genetic diversity, 3) the maintenance and loss of polymorphism, and 4) the genetic basis of polymorphic mating phenotypes. His main study system has been the side-blotched lizard (Uta stansburiana), a species that is polymorphic for three different male mating strategies characterized by distinct throat colors and mating behaviors. The mating strategies are maintained by an evolutionary analogue of the rock-paper-scissors game wherein orange males take territory from blue males because they are more aggressive, yellow males beat orange males by sneaking onto their large territories, and blue males beat yellow males by closely guarding their mates. Ammon is currently investigating the genetic basis of these different mating types using next-generation sequencing methods. The goal of this project is to better understand how distinct mating types evolve within a species and how color signals are linked to behavioral differences.

Umilaela crossing Sungai Alas (the largest river in Aceh) while conducting fieldwork in Gunung Leusser National Park on the Indonesian island of Sumatra.


Umilaela Arifin: Umilaela is broadly interested in the amphibians and reptiles of Southeast Asia, with a special interest in those occurring in Indonesia. She is particularly interested in amphibian morphology, phylogenetic systematics, evolution, phylogeography, ecology, behavior, and conservation. Her research is currently focused on the evolution and ecology of ranid frogs with gastromyzophorous tadpoles (tads with stomach suckers for adhering to rocks in swift-flowing streams). Umi officially joined the lab with a Marie Curie postdoctoral fellowship in March but is currently safely ensconced in Germany as the US suffers through the Covid-19 pandemic. 

Umi’s research was recently showcased on the SSAR website!

Simon and a photogenic Sceloporus cowlesi in New Mexico.


Simon Scarpetta: Simon’s broader research areas include phylogenetics, biogeography, and paleontology. He often studies lizards but is interested in all reptiles and amphibians. Simon has a persistent interest in the practice and theory of using phylogenetically-explicit approaches for fossil identification, and the effects of those approaches on divergence time, biogeographical, and paleoecological hypotheses. For his postdoctoral research, Simon is studying the phylogeny and biogeography of iguanian lizards using phylogenomic and paleontological datasets, and will also investigate hypotheses of niche conservatism among pleurodontan lizards. Recent projects explored osteology and phylogenetics of alligator lizards, divergence times and paleoecology of North American fringe-toed lizards (Uma), and the effects of phylogenetic uncertainty on fossil diagnosis. 

Graduate Students:

Sina admiring a rarely encountered Corallus caninus (and trying not to be bitten in the face) deep in Ecuadorian Amazonia.

Sina Amini: Sina spent a year living in the forests of Ecuador and has a deep and abiding love of the amphibians and reptiles of tropical America. However, after arriving at UC Berkeley he became fascinated by the evolutionary basis of sexual dichromatism and an unusual polymorphism exhibited by various hummingbird species in which some females exhibit male-like plumage. Thus, for his doctoral research, Sina is investigating the evolutionary and hormonal basis of this unusual phenotypic outcome, with a special emphasis on the hummingbird genus Heliangelus.

Charlotte at Dove Lake on Cradle Mountain while performing fieldwork in Tasmania

Charlotte Jennings: My research centers on spatial patterns of biodiversity and the evolutionary and ecological processes that shape them. For my dissertation, I am focusing on the latitudinal diversity gradient, or why species diversity is highly concentrated in the tropics. I take an approach that incorporates eco-physiology, biogeography, and phylogenetics. In particular, I’m investigating variance in thermal-physiological traits among related skink species that occur at different latitudes and altitudes, from temperate Tasmania to tropical Papua New Guinea. This required that I develop basic thermal physiology protocols to facilitate experimentation on populations in these very remote locations. Intrinsic traits, such as physiology or behavior, are factors that govern a species sensitivity to environmental change.

Ben makes his way down Gunung Katopasa on Sulawesi’s Eastern Peninsula after dislocating his shoulder while descending (ok, falling) down a waterfall

Ben Karin: Ben broadly studies evolution, phylogenetics, and systematics, and is focusing his dissertation research on scincid lizards on Borneo and Sulawesi. He is particularly interested in three clades of forest-floor scincid lizards (Eutropis, Sphenomorphus, and Tytthoscincus) that show distinct differences in life-history, vagility, and lineage diversity. These clades present a compelling comparative system for investigating the processes by which clades of closely related species have diversified on either side of Wallace’s Line and how their island-wide communities have been assembled. Ben is investigating the phylogenetics and phylogeography of these groups both within and between islands, as well as species turnover and evolution across elevational gradients.

Isaac also enjoys serving as a basking site for the rarely-encountered Phrynosoma arboreans

Isaac Krone: Isaac is interested in integrating modern diversity with long-term patterns in vertebrate evolution. Previous work centered on using geometric morphometrics to investigate large-scale functional and allometric trends in morphology in wrasses and non-mammalian synapsids. For his dissertation, he plans to investigate the interplay of geographic and morphological constraint & lability in the evolution of convergent morphotypes and ecologies within reptiles and amphibians, especially with respect to the evolution of extreme morphologies such as limb reduction in lizard lineages.

Alexander attempting to extricate the Land Cruiser from the deep mud of Gunung Latimojong in Sulawesi’s Central Core

Alexander Stubbs: Alexander is interested in signal evolution and sensory biology as well as using genomic tools to better understand phylogenetic and evolutionary questions in reptiles and amphibians. He has studied mechanisms and optimization of color vision in reptiles and also in organisms previously thought to be colorblind (e.g., cephalopods). Alexander is also interested in signal processing and studying signaling and sensory systems. He also loves tropical reptiles and amphibians, with a primary focus on eastern Indonesia.

Undergraduate Students:

Kayla Walzer: Kayla performed her Honor’s Thesis research working with Ben Karin and Jim investigating the genomic basis of a wing color polymorphism in the Sulawesi flying lizard species Draco beccarii. She performed scans of 16 D. beccarii genomes, eight representing yellow-winged males and either representing orange-winged males. Her sliding window Fst scans of the genomes successfully identified two regions of the genome strongly correlated with the wing-color polymorphism, which we will further explore with additional genomes.

McGuire Lab Alumni