by Sally Logue Post
Meet the Researchers
Ximena Bernal is a professor in the Department of Biological Sciences in the College of Arts and Sciences.
Michael San Francisco is a professor in the Department of Biological Sciences in the College of Arts and Sciences, Associate Vice President for Research (Faculty Development) in the Office of the Vice President for Research, and an Associate Dean in the Honors College.
Highlighting Texas Tech Amphibian Research
The world’s frogs and other amphibians are disappearing at an alarming rate. In the past 30 years, about 200 amphibian species have vanished – that translates into the loss of about one species every two months.
Scientists know it is happening; the question is why? Texas Tech University biologists Ximena Bernal and Michael San Francisco are trying to understand the factors contributing to the increased mortality of these important animals.
“Frogs are great bio-indicators of environmental changes in our world,” Bernal said. “Amphibians are sensitive to potential toxins in both the water and in the soil. If they are dying out, then it is telling us we may have problems.”
Frogs face threats on several fronts, including pollution, disease, habitat loss, climate change and overharvesting by the pet and food industries.
“Frogs are very important to our ecosystem,” Bernal said. “They eat insects such as mosquitoes that carry diseases that harm humans and animals. And they in turn are food for other creatures. If frogs disappear, then the food chain is disrupted, and we do not know what kind of negative ramifications that would have on other species.”
Fast Frog Facts
- 2,000 amphibian species are threatened with extinction and may not survive the 21st century.
- 200 amphibian species have already become extinct since 1979.
- 165 amphibian species are believed to have already become extinct.
Source: Amphibian Ark
Bernal is looking at frog behavior. One area of concentration is determining why some amphibians are flourishing. For example, the cane toads are thriving in Puerto Rico, Hawaii and Australia.
“We are trying to learn why this toad is successful,” she said. “Perhaps they are just really smart or really adventurous. It appears they are able to learn how to adapt to changing food supplies and conditions as they invade new areas.”
Many amphibians will only eat food that moves. Yet the cane toad has learned to consume things that do not move, such as dog food.
Bernal also is looking at – or listening to – how frogs talk to each other.
“Frog calls are different from each other and as distinctive as bird songs or human accents,” Bernal said. “In most frog species only the males call, hoping to attract a female. Their calls may also attract flies that feed on the frog’s blood and in the process are transmitting potentially fatal parasites to the frogs.”
Another potential threat to frogs is a type of fungus called Batrachochytrium dendrobatidis, or Bd. San Francisco and his team are trying to understand how the fungus works and how it kills.
The fungus affects the outer layer of a frog's skin, making it thick, and may result in skin loss. For amphibians, that is deadly because they absorb water and essential salts through the skin and not the mouth. Additionally, much of a frog's gas exchange occurs through its skin.
“Frogs are a critical component of our ecosystem,” he said. “This fungus is like the plague. It is the worst infectious disease to ever hit wildlife on this planet. If we can find a weakness in the fungus, we can maybe find out how to treat it or get rid of it. It’s important that we find out more about the biology of the fungus in order to stop it. We don’t know how or where the fungus will move next if our amphibian population is decimated.”
Setting a World Record
As part of the effort to draw attention to the threat to amphibians, Texas Tech students, faculty and staff set a world record for the most people in one place wearing frog masks, according to the World Records Academy.
About 700 people donned the froggy faces for the event on April 29, Save the Frogs Day. Students in Bernal's lab organized the event.
“I am very excited and extremely proud of the great job carried out by the undergraduate and graduate students in my lab, but also proud of our community at Texas Tech that responded positively to our plea for amphibians,” Bernal said. “I see breaking this world record as yet another way to increase the group of people we are reaching to share our concerns about the plight of frogs and toads.”
Click images to enlarge. Save the Frogs Day images courtesy Kristina Woods Butler.
Sally Post is Director of Research & Academic Communications for the Office of the Vice President for Research at Texas Tech University. Images courtesy Neal Hinkle.