Catawba College Professor Part of Madagascar Genetics Study
April 9, 2020
Catawba senior Zachary Johnson in Madagascar with a black and white ruffed lemur
Dr. Luke Dollar, Chair of the Department of Environment and Sustainability at Catawba College, is part of an international team of scientists who recently released a genetics study on the origins of the “forest cat” on the island of Madagascar.
The study, with genetic analyses by Michelle Sauther of the University of Colorado and colleagues, indicates that the cats were brought to the island by Arab trading ships 1,000 years ago. The cats are descendants from domestic cats of the Arabian Sea region, which includes the islands of Lamu and Pate, Dubai, Oman, and Kuwait.
The study was released in the journal Conservation Genetics, with coverage by news media such as CNN and Atlas Obscura. The article in Atlas Obscura, written by Jennifer S. Holland, states that the origins of the oversized, tiger-striped, lemur-eating feline have been the subject of much debate.
According to the Holland article, “Many scientists have long thought that the feline’s ancestors were small wildcats that somehow reached Madagascar from mainland Africa.
Others posited that Felis catus, the domestic cat, was also part of the gene pool (though historical and ethnographic data suggest that domestic cats didn’t arrive at Madagascar until the 1800s – with a U.K. ambassador – after the forest cat was already established on the island nation).
The Holland article states, “For wildlife managers, learning more about these forest cats can help them decide what, if anything, should be done about them. Filling in details of the forest cats’ origins leads to a complex and big-picture question for conservationists: At what point is an invasive species considered part of the fabric of the environment it once established? Is 900-plus years long enough?”
Dollar, a National Geographic Society Explorer, has logged a decade of calendar time in Madagascar since a first trip there in 1994, doing conservation work, research and education, helping economic development, and helping build 40 schools.
This African island in the Indian Ocean is the fourth largest in the world, approximately the size of California and Oregon combined, and is sometimes called the eighth continent.
Currently, Dollar spends three to four months a year in Madagascar. "Working in one of the world's poorest countries creates a sense of humility and responsibility to do more," he says. "It reinforces the idea that merely because of where we were born ... because of the randomness of our birth ... we are beneficiaries. We have a greater responsibility. We need to be part of the solution, rather than exasperating the problems."
As for the question of when should an invasive species be considered part of the environment, Dollar says in the Atlas Obscura article “that is quite the conundrum. When is it no longer justifiable for managers to (interfere with invasive wildlife)? Especially when Madagascar is weighted down by many more acute conservation problems, such as population growth, lack of infrastructure, and the devastating effects of traditional agricultural practices.”
Sauther, of the University of Colorado, says, “Is this a case where we should focus our efforts elsewhere – where we should leave a thing alone and let nature take care of itself? …. Regardless of what decisions are made going forward, these findings give us insight into how things from outside adapt and change an existing ecology. We know humans came into Madagascar and changed a lot – cutting forests, raising cattle, planting crops. There were waves of heavy human impacts. And these cats are part of that story.”
Tim Telzlaff, chair of the Madagascar Fauna and Flora Group, an international consortium of zoos and conservation organizations, says, “Whether the ancestors were beloved pets, ship ratters, or sneaky stowaways, these findings are consistent with human migration patterns of people arriving from the east. With so many fundamental mysteries about Madagascar’s past, beginning with how its iconic wildlife even got here, it’s gratifying to have any one of these questions sorted.”
Dollar says, “Madagascar has exceptionally diverse habitats and a host of species that evolved on the island and live nowhere else. It has its own small carnivores. The largest, called the fosa (or fossa), is often described as ‘cat like’ – or, some say, a cross between cat, mongoose, and dog – though it is not actually a felid. A member of the Euleridae family, which covers all of the island’s meat-eaters, it prefers a deep-woods habitat and leans on lemurs for much of its nourishment. Fosa are only found on Madagascar; they are meant to be there,” he adds. “They evolved to be, and remain, the top predators of Madagascar’s intact forests.”
The study included Dollar’s team and others trapping and drawing blood from dozens of forest cats in two Malagasy protected areas. The scientists compared forest-cat genes to a host of cat genomes from around the globe.
Dollar says, “The forest cats prey on native birds, rodents, and snakes, and compete with the fosa for the endemic lemurs. But their estimated date of arrival means that they’ve spent centuries living on and adapting to Madagascar, becoming part of the island’s ecosystem as it functions today. They occupy the forest edges really, really well – a case of a non-native species snagging relatively new digs (areas disturbed by human development) that competitors haven’t occupied. And with so many centuries as co-residents, he says, “things may be relatively balanced.”