“Poop science” is becoming increasingly used by a wide-range of scientific fields and can be used to study anything from animal health and microbiomes to population genetics and animal trafficking. Not only can faeces help answer scientific questions, but it can do it in a non-invasive way.

Although not everything can be answered with this method, lemur researchers are finding answers to both new and old scientific questions as well as inform conservation efforts for wild and captive lemurs around the world.

The conservation duty of science

While many people have probably seen the iconic ring-tailed lemur at a zoo, most other lemur species do not survive well in captivity. In particular, lemurs that eat leaves, known as folivores, do not do well in captive settings. But these folivorous species, such as the sifakas and the indri, are also some of the most endangered of lemurs.

Thus, the goal of much lemur research is not only to study how wild lemurs interact with their natural habitats, but to also understand how to better take care of lemurs in captivity. This is where poop science comes back into the picture.

Getting inside the lemurs’ guts (harmlessly)

As a lemur poop scientist, I spend a lot of time thinking about how lemur poop can be used to help lemurs in the wild and in captivity. In particular, I am interested in understanding how a lemur’s environment affects the bacteria that live in their guts.

All mammals, including humans and lemurs, have trillions of bacteria living on and inside them. But, much like the word “poop”, the word “bacteria” doesn’t usually evoke a positive response. Well, they should. Bacteria are actually a vital part of any animal. These communities of microorganisms, known as microbiomes, are vital to keeping an animal healthy.

Sally being a lemur

Sally impressing a lemur at being a lemur (Credit: Sally Bornbusch)

The gut microbiome, in particular, helps with food digestion, reducing inflammation, and protecting against infection and disease. And if this community is disturbed or wiped-out, there can be serious consequences for the animal’s health. In many ways, the gut microbiome acts as an indicator of the animal’s health and well-being.

But how do you study the gut microbiome without actually getting at the animal’s gut? Yep. You do it through their poop. When poop is formed in the intestines, the bacteria that live there get wrapped up with the rest of the faecal material and deposited out when the animal defecates. Each faecal sample has a ‘mini microbiome’ that represents the larger community within the animal’s gut. Thus, lemur poop can tell us about what the lemurs eat, what bacteria they have in their guts, and ultimately whether that lemur is healthy.

Lemur hangover

My research focuses on understanding the environmental factors that help shape lemur gut microbiomes. Does a lemur’s microbiome depend on their diet, their habitat quality, or perhaps their exposure to humans or medicine?

By collecting poop from lemurs that live in different environments (i.e. deserts, forest, or in a captive facility) and are exposed to different conditions (i.e. different diets, human contact, and antibiotic treatment), I can look at the differences in their gut microbiomes and begin to determine why some lemurs are more ‘healthy’ in certain environments. The results of this research can then be used to make decisions on things like how to improve lemur health or how best to care for lemurs in captivity.

For example, much of my lemur research is performed at the Duke Lemur Center (DLC), a facility that focuses on education and non-invasive lemur research. The DLC has the largest population of lemurs anywhere outside of Madagascar.

Although the DLC has been wildly successful at caring for lemurs in captivity, it is always important to try and improve our understanding of how captivity affects lemur health.

One of my current projects is concerned with determining the effects of antibiotic treatment on the gut microbiomes and health of lemurs living at the DLC. Antibiotics are used to treat infections in captive animals, but because many antibiotics are broad-spectrum, they often wipe out good bacteria along with the bad. This can disrupt the gut microbiome and lead to nasty side-effects or worse infections after antibiotics treatment.

Again, through poop science, I aim to determine exactly how a lemur’s gut microbiome changes with antibiotic treatment. What bacteria are killed? How does the microbiome recover after antibiotics? What happens if there are side-effects? This research will help prevent the detrimental side-effects in the future and also help scientists and veterinarians come up with alternatives to antibiotics. Although that particular research is aimed at improving the care of captive lemurs, most of the lemur poop science takes place with individuals in the wild in Madagascar.

Poop tracing illegal pet hunting

Another of my larger poop science projects is looking at how ring-tailed lemur microbiomes differ across a wide geographical scale. In this study, I needed faecal matter from lemurs living all over Madagascar. But, for a grad student like me who cannot go to Madagascar every other day, that is a big challenge.

So, I asked for the help of other lemur poop scientists, namely, the scientists who work with Lemur Love, Drs. Tara Clarke (you can read about her amazing work on lemur and social networks on the Plan A academy too!) and Marni LaFleur. Lemur Love is a non-profit organization that focuses on lemur research and conservation and is a big proponent of poop science. They use poop from wild ring-tailed lemurs, illegal captive pets, as well as rescued ex-pets to answer questions about the genetic diversity and population structure, as well as to combat the illegal pet trade.

In Madagascar, lemurs are sometimes kept as illegal pets to attract tourists. However, lemurs are wild animals: Taking them out of the wild is bad for them and they do not make good pets. The scientists at Lemur Love use poop science to try and “pinpoint geographic hotspots for the illegal capture of individuals for the pet trade”. Through this research they hope to reduce illegal pet trade and its impunity.

Poop saves lives

So, what’s next from poop science? Surprisingly – for the non-initiated –  poop is becoming increasingly popular not only in science, but in medicine and veterinary protocols. Specifically, there is a lot of interest around faecal transplants. And here you can put down your food. Faecal transplants are used (in both lemurs and humans) to treat individuals that have gastrointestinal infections. It entails using faeces from a healthy individual, and transplanting it into the gut of the unhealthy individuals.

Lemurs don't like cages

The idea is that the microbiome of the healthy individual can help fight off the infection in the sick one. Among lemurs, many species are difficult to keep in captivity because they frequently get gut infections. The veterinary and research team at the DLC have been successfully using faecal transplants to prevent and fight infections in their lemur populations. But, sometimes humans need faecal transplants too. Clostridium difficile is an illness that can cause severe and reoccurring gastrointestinal infections in humans. And, one of the treatments is faecal transplants, or as some call them, poop pills. Now this may sound gross but a poop pill in one of the only successful ways to treat painful and persistent C. difficile infections.

Do primates poop equally?

While my research focuses on lemur poop, other scientists focus on human poop. But, that is not to say that what we learn about lemurs can’t apply to humans. Lemurs and humans are both primates, meaning we share a common ancestor. Although you might not think it from looking at a lemur, humans and lemurs are relatively closely related cousins. By researching lemurs, we can also learn a lot about human ecology, evolution, and health.

Ultimately, the goal of lemur poop science, including my own, is to help the lemurs, whether they are in a centre in the U.S. or in a forest in Madagascar. I often get asked why I spend so much time thinking about lemur poop. The reason I do my research is not just to answer scientific questions, but to learn more about these amazing animals and help with the conservation of the last of their populations.

Sally Bornbusch is Ph.D. student in the Evolutionary Anthropology Department at Duke University. She loves to work with animals of all shapes and sizes, but lemurs are her favorite. She is also an avid nature photographer and hopes to use her photography to teach children about the beauty and importance of the natural world and its animal inhabitants.