A Bit More Detail

Assorted Personal Notations, Essays, and Other Jottings

[LINK] “Say We Really Do Bring the Passenger Pigeon Back From Extinction — Then What?”

Wired Science’s Greg Miller makes the point in connection with passenger pigeons, but relevant for other species, that simply cloning a recently extinct species back into existence won’t necessarily make it viable in the wild. All sorts of critical environmental and genetic traits won’t be copied–how will a species of cloned neonates learn to live in the wild? How can they, without viable parent figures? And what about their environment, which by definition had changed sufficiently to make their species non-viable in the first place?

“Everything we know about species and individuals tells us that we’re a lot more than our genes,” said David Blockstein of the National Council for Science and the Environment.

For one thing, an animal’s genes are influenced by its environment though chemical changes to DNA that affect how genes switch on and off.

Those “epigenetic” changes may be a crucial part of what gives a species its unique characteristics, but the epigenetic profile of a bird created in a lab would never be the same as that of a bird raised in a flock by its natural parents, Blockstein says.

Conservation biologist David Ehrenfeld of Rutgers University is skeptical too. ”Let’s say we could create a passenger pigeon with the same DNA and the same epigenetic marks,” he said. “That doesn’t make it a passenger pigeon.”

Ehrenfeld and others say passenger pigeons were perhaps the most social birds that have ever existed, living in flocks of hundreds of thousands. “They needed enormous populations to nest properly and repel predators,” Ehrenfeld said. Their behavior, as much as their DNA, defined the species.

Written by Randy McDonald

March 28, 2013 at 6:51 pm

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