Carbon Copy Critters: Cloned Species and the Endangered Species Act

Emily Kennedy, MJLST Staffer

The United States is home to over 1,600 species listed as threatened or endangered. These species face a number of challenges arising from human activity, such as habitat loss from encroaching human populations, pollution, climate change, and excessive hunting. While species such as the Houston toad or the Government Canyon bat cave Spider may seem insignificant, and perhaps a bit frightening, each species is an important part of an intricately connected biotic community. Losing a few species could trigger an “extinction domino effect” that results in ecosystem fragility and the loss of more and more species. The Endangered Species Act was designed to protect species and their ecosystems. While the Act did not contemplate cloning of endangered species, cloned animals are also protected.

The black-footed ferret (Mustela nigripes), a small mammal that historically inhabited the United States’ western mountain prairie region, is among the species listed as endangered. Black-footed ferrets were nearly wiped out entirely as a result of human efforts to kill them to ensure that prairie ranges were better suited for cattle. In fact, they were thought to be extinct until they were rediscovered and scientists captured the remaining animals for a captive breeding program.

Scientists recently announced the birth of Elizabeth Ann, a black-footed ferret who is the first clone of an endangered species indigenous to the United States. Born to a domestic ferret surrogate, she was cloned from a wild black-footed ferret named Willa who died and was frozen in 1988. After her death, Willa’s tissues were sent to a “frozen zoo” that retains genetic materials for over 1,000 species. Viagen, the company that cloned Elizabeth, also recently cloned an endangered Mongolian horse and will clone pet cats and dogs for a hefty fee of $35,000 to $50,000. Elizabeth and any future clone siblings will remain in the possession of scientists for study, with no plans for release into the wild.

The Endangered Species Act was signed into law in 1973 to protect the plant and animal species threatened with extinction in the United States. One commentator has argued that an “aggressive federal governmental policy of cloning endangered animal species would be consistent with the language and spirit of the Endangered Species Act as interpreted by the courts.” Additionally, “lack of genetic diversity in species revived in the laboratory should not preclude [Endangered Species Act] listing.” This was the case with the listing of a plant known as the Franciscan manzanita. Much like the black-footed ferret, the Franciscan manzanita was thought to be extinct until a single plant was discovered. Genetically identical clones were then propagated from cuttings from that plant.

Cloning is a cutting-edge and high-tech practice, but that does not mean that it is a panacea for species extinction concerns. Firstly, the process of cloning wild animals is successful only around 1% of the time. But the primary problem is that many species succumb to extinction due to habitat loss or fragmentation. Cloning does nothing to solve this issue, since cloned animals will still lack the habitat they need to thrive.

Further, genetic diversity is already a concern for many endangered and threatened species. Because they were nearly wiped out as a species before they rebounded in a captive breeding program, black-footed ferrets, like the one Elizabeth was cloned from, descend from seven closely related individuals. Such genetic homogeneity results in increased susceptibility to some diseases. Currently, cloning does not address this concern and may even exacerbate it, by relying on genetic material from even fewer individuals. However, some hope that manipulating the genome to improve genetic resistance is a “possibility in the future.”

While cloning may not be a complete solution to increasing species extinction, some think that it is a useful tool to address the complex problem of extinction in conjunction with other measures. Perhaps in the future, cloning can offer a high-tech option that works in concert with more established methods such as habitat restoration and conservation, captive breeding programs, and measures to address climate change.