Prolonged drought could affect the microbiomes of Panamanian lizards

A study conducted in Panama shows changes in the microbiome of the lizard Anolis apletophallus that are associated with drought.

The results show that long-term drought, not short-term warming, changes the gut microbiomes of these animals.

Doctoral student Claire Williams and scientist Michael Logan led the research under the auspices of the Smithsonian Institute.

A microbiome is a set of microorganisms (viruses, bacteria) and their genes in a certain environment. The intestinal microbiome, on the other hand, refers to the microorganisms that live in that part of the host’s tract.

Williams’ PhD thesis focused on how the microbiome can help lizards adapt to new environmental conditions such as warming and drought.

To conduct the study, the researchers moved some lizards from the tropical forest on the mainland to islands, which are warmer and drier.

Some of the land lizards were placed in a greenhouse to mimic the temperature changes the lizards experienced on the island. It was important for the researchers to include a more controlled experiment so they could determine which changes in the gut microbiota were due to warming and which changes were due to the different environments on the islands.

Scientists expected warming on the islands to make a difference, but that’s not what they found.

Williams said that in 2019, all the microbiomes studied looked similar, both those on the islands and those on the mainland.

“The data showed that the microbiomes of the lizards were more influenced by the year they were sampled than by the effect of moving to warmer islands,” he added.

In this sense, the severe drought that occurred in 2019 could have affected both lizard populations in the same way.

It is still not clear why the drought affected the gut microbiome. The drought could have changed the environment in which the lizards live, for example by changing their food source or the amount of water they drink.

“The fact that the microbiome is changing in response to drought doesn’t necessarily mean that the microbes are improving their ability to survive. There’s a lot of work to be done,” he said.

According to Williams, the study is important for understanding how microbiomes can influence processes that support animal health and survival.