Studying hybrid lizard species through DNA

by Jared Grummer 

I often wonder what non-scientists think of my research: why would people care about lizards that most will never see? When I say I study hybrids, do they think I mean hybrid cars? Hybridization, or interbreeding between distinct species, of lizards in Argentina is a very foreign idea for most, in more ways than one.

Liolaemus "melanops", though this likely represents an undescribed species.

There's hope for the survival of frogs

Leopard running frog, Kassina arboricola.
Photo by Duncan Reid.

Amphibians are one of the most threatened animal groups in the world; almost one third of all species are under severe threat. One of the main reasons for this is a nearly worldwide distribution of a chytrid fungus that causes a highly-lethal disease in frogs, called Chytridiomycosis. The fungus attacks the skin and blocks respiration in infected frogs, eventually killing the animal.

Chytrid is particularly widespread in Africa, with new positive records reported from countries in southern, eastern, and central Africa each year. One hypothesis is that the chytrid fungus originated in Africa and dispersed globally via the pet trade.

Cloudy with a chance of horned lizards

Many people go to Mexico for a relaxing beach vacation. But Burke scientists spent their "summer vacation" searching the desert for signs of the elusive horned lizard.

Horned lizards are especially diverse, including sixteen species that vary dramatically from each other (picture Thanksgiving dinner, when you're wondering how that crazy cousin could POSSIBLY be related to you).

Some give live birth like humans, while others lay eggs. Some can squirt blood out of their eye as a defense mechanism against predators, while others can’t. Not to mention, horn and tail lengths vary dramatically between the species. How, where, and why did these lizards adapt so differently from one another?

Burke Grad Students Awarded NSF Fellowships!

Congrats to two UW graduate students working with Burke Curator of Genetic Resources and Herpetology, Adam Leache: Matt McElroy and Rebecca Harris! They were recently awarded prestigious National Science Foundation Fellowships. The fellowships strive to fund graduate students who have a history of being successful at research and outreach. The fellowship provides three years of funding, allowing Matt and Rebecca to dedicate more time to research. It’s no wonder they were awarded this prestigious award, they’re both studying really cool things!

Matt is interested in how lizards adapt to different thermal environments and will be traveling to Puerto Rico to study Anolis lizard species.

Matt: “I am interested in how lizards adapt to different thermal environments. Since lizards absorb heat from the sun and their surroundings, the habitat a lizard finds itself in will influence its body temperate and physiological performance. On Puerto Rico in the Caribbean, species of Anolis lizards utilize either cool closed-canopy forests or hot open-canopy habitats. Interestingly, closely related species in this group use different thermal environments, indicating that species may have diversified when populations adapted to different thermal habitats. At some point in Puerto Rico’s past, four species split into eight, and my research aims to understand how and why this happened.”

Matt: “I am really excited to go to Puerto Rico and collect lizards and genetic material for this project. Doing fieldwork is an amazing experience – you learn a lot about new habitats, new animals, new cultures, even new things about yourself. As I prepare for summer fieldwork, you may find me reading articles in the office or practicing my baile de salsa out on the dance floor!”



Rebecca is pursuing how species change through hybridization and how large chunks of DNA are transferred when two different species hybridize.

Rebecca: “Evolution occurs at multiple different levels, including changes in the structure and organization of chromosomes. I’m interested in the role of these changes in speciation and how these large chunks of DNA transfer when two different species hybridize. In 1983, the Pytilia finches, a genus of African finches, were shown to have numerous chromosomal rearrangements, but no technology was available to look any closer at these areas. Now, thanks to the human genome project, there are techniques available to explore the actual nature of these rearrangements – a task made even easier by the completion of the zebra finch genome. My proposed study system is a two Pytilia species thought to be hybridizing in the mountains of Malawi.”

Q: Where are rattlesnakes found in Washington State?

Rattlesnakes are among the most feared, and perhaps misunderstood, reptiles out there. The last thing many people want to hear is the ominous shake of a rattler. So many may wonder:

Q: Where are rattlesnakes found in Washington State?

A: The only rattlesnake species found in Washington State is the Western rattlesnake (Crotalus viridis).  Western rattlesnakes live in warm, dry habitats of desert shrub, grasslands and open pine forests.  Because of these habitat needs, rattlesnakes do not live in Western Washington and only inhabit the eastern side of the Cascade Mountains and eastern parts of the Columbia River Gorge.

Western rattlesnake. Photo by Brad Moon

Rocky habitats are the most common areas to find Western rattlesnakes.  Although these snakes are venomous, they rarely use their well-known rattles and are generally calm creatures.  In fact, they’d much rather remain still and go unnoticed by predators and people by staying quiet and out of the way. 

During the late fall and winter, Western rattlesnakes often hibernate in rock crevices on south-facing slopes, and may be joined in their dens by other snake species as well.  The rattlesnakes emerge from the dens when the weather is warm enough to take them out of a state of torpor, usually between February and April. 

To learn more about other Washington State reptiles, click here.

The Burke Museum partners with the Seattle PI's Big Blog to answer commonly asked questions about the natural and cultural history of our region. This post originally appeared on the Big Blog on March 21.

Posted by: Andrea Barber 

New Curator of Genetic Resources and Herpetology Arrives!

At the beginning of this month the Burke Museum welcomed a new curator of genetic resources and herpetology to the museum, Adam Leaché. Adam first visited the Pacific Northwest in 1997 as a graduate student, when he attended his first major academic conference – the annual meeting of the American Society of Ichthyologists and Herpetologists – at the University of Washington. Over a decade later, he returns to Seattle with a brand new curatorial position at the Burke Museum and a joint appointment as an assistant professor of biology at the University of Washington.

New Burke curator of genetic resource and herpetology, Adam Leaché, poses with a Komodo dragon.

Dr. Leaché will oversee both the genetic resources collection and the herpetology collection (reptiles and amphibians) at the Burke Museum. He is already planning several collecting trips for the museum, including field trips to West Africa, Mexico, and the deserts of the American Southwest. Dr. Leaché is also particularly interested in expanding the catalogue of specimens collected in the National Parks of Washington State.

In addition to focusing on the growth of the genetic resource and herpetology collections, Dr. Leaché is enthusiastic about developing public outreach programs for the Burke. One of his hopes for his new position is to help bring funding to the museum for the development of exhibits and educational content about ecology and evolution studies.

Dr. Leaché’s own research is focused on systematics, phylogenetics, phylogeography, population genetics, and species delimitation. Over the last ten years, he developed an integrative research program exploring the evolution of North American fence lizards and horned lizards that has resulted in publications across a number of disciplines. During the winter quarter, Dr. Leaché will be teaching an applied phylogenetics course at the UW – a lab course that gives biology students the computational and bioinformatics skills necessary to organize and analyze genetic data.

The Burke is excited to have Adam Leaché on board!