(One of the new species, Apomys brownorum; Credit: Velizar Simeonovski, The Field Museum)

Seven new species of mammals have just been discovered at Luzon Island in the Philippines, according to a Field Museum press release.

The discoveries increase the number of native mammals known from that island from 42 to 49, an increase of 17 percent. The new animals are all field mice. (With over 2,000 living species, rodents are by far the largest group of mammals.)

All of the new species belong to the genus Apomys and are described in the latest issue of Fieldiana.

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"These animals are part of the rich biological heritage of the Philippines," Theresa Mundita Lim, Director of the Protected Areas and Wildlife Bureau, Department of the Environment and Natural Resources (DENR), was quoted as saying in the press release. "The forests where they live are crucial watershed areas for Manila and many other cities. Protecting their mountain forest habitat is good for them and for people."

Each of the seven species of forest mice lives in its own small section of Luzon.

Lawrence Heaney from The Field Museum, project leader and lead author of the publication, explained, "These are wonderful little mice that live in forested regions high in the mountains. Although they are often abundant, they actively avoid humans and rarely cause any harm. They prefer to eat earthworms and seeds on the forest floor."

Two of the new species live only in the Zambales Mountains (on Mt. Tapulao), two live only on Mount Banahaw (south of Manila), two only in the Mingan Mountains of Aurora Province, and one lives only in the Sierra Madre of northeastern Luzon.

"It is extraordinary that so many new species of mammals remain to be discovered in the Philippines," according to Danilo Balete, leader of the project's field team.

"In the past 10 years we've published formal descriptions of 10 other species, and other biologists have described five more. And we are nowhere close to the end of our discoveries. The Philippines may have the greatest concentration of unique species of animals of any country in the world."

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Scott Steppan, co-author and head of the laboratory at Florida State University where the DNA portion of the study was conducted, said, "The Philippines is an ideal place to study the evolution of animal diversity, even better than the famous Galapagos Islands. These animals have been evolving in the Philippine archipelago for millions of years."

Romeo Trono, Country Executive Director for Conservation International – Philippines, said, "Protecting land and marine resources is key to maintaining healthy ecosystems which deliver ecosystem services such as food, clean water, health, tourism and cultural benefits and stable climate which are vital to the very survival of every Filipino. Although small in size, these little animals are part of our biodiversity which forms the basic foundation of healthy ecosystems."

M. Josefa Veluz, biologist at the Philippine National Museum and co-author of the study, reminded that only a few of the new species (those from the Sierra Madre and Mt. Banahaw regions) live within protected areas. The others do not, and are threatened by logging, expansion of agriculture and mining activities.

If predictions hold true, the region will yield more new species discoveries in future, hopefully permitting expansion of protected regions on the animal and plant-rich island.