Question

Breed and release programs have been very successful in returning endangered species back to the native environment.

Question 4 options:

	True
	False Please highlight answer.

Answer 1

Ans- True

There are three main approaches to de-extinction scientists talk about. The first, called backbreeding, involves finding living species that have traits similar to the extinct species. Then scientists would selectively breed these animals to try to make a version that more closely resembles the extinct animal—a process already underway for some extinct species like aurochs. This isn’t really a true de-extinction, but it might still let us fill in missing ecological functions. In the case of mammoths, scientists might try to mate Asian elephants with more body hair than usual, for example.

A second option is cloning. Scientists would take a preserved cell from a recently extinct animal (ideally before the last of its kind died) and extract the nucleus. They would then swap this nucleus into an egg cell from the animal’s closest living relative and implant the egg into a surrogate host. (Researchers actually did this in 2007, and a common goat gave birth to an extinct species, the Pyrenean ibex. The infant lived only 7 minutes however, because of genetic problems with its lungs.) Cloning may eventually give us basically identical genetic copies of extinct species, but we’ll be restricted to animals that went extinct more recently and have well-preserved cells with intact nuclei. The mammoth and the passenger pigeon may never be cloned.

The newest option is genetic engineering. Here, researchers would line up the genome of an extinct animal with that of its closest living relative. They would then use CRISPR and other gene-editing tools to swap relevant genes from the extinct animal into the living species and implant the hybrid genome into a surrogate (or grow it in an artificial womb). This approach doesn’t produce genetically identical copies of extinct animals, but rather modern versions of an animal engineered to look and behave like its extinct relatives. This is the technology being used by the mammoth and passenger pigeon groups.

The study findings suggest conservation programs that use wild-caught mammals are more likely to succeed than those that rely on animals raised in captivity.

Yet captive carnivores still have an important conservation role to play, Jule said, "because increasingly there are not enough animals left in the wild that we can move."

Improved reintroduction techniques are needed to make captives a more viable option, she said.

The researchers argue for better prerelease training, which allows zoo-bred carnivores to improve their hunting skills and adjust to natural social groups.

Better selection criteria for choosing animals for release are also required, Jule said.

Research shows, for instance, that "animals that are more bold, particularly toward humans, are more likely to die," she said.

Similarly animals that are less hesitant about venturing beyond reintroduction areas are at increased risk, she added.

Improved survival rates are also important from an animal welfare standpoint, Jule said.

"Having animals starving to death is obviously not ideal," she said. "If we can train them for life in the wild a bit better, it not only improves their welfare but also a project's overall success."